Skip Navigation
Skip to contents

JPMPH : Journal of Preventive Medicine and Public Health



Page Path
HOME > J Prev Med Public Health > Volume 49(3); 2016 > Article
Original Article
Risk Factors for Preterm Birth and Low Birth Weight Among Pregnant Indian Women: A Hospital-based Prospective Study
Chaitanya Tellapragada1orcid, Vandana Kalwaje Eshwara2orcid, Parvati Bhat3, Shashidhar Acharya4, Asha Kamath5, Shashikala Bhat3, Chythra Rao5, Sathisha Nayak3, Chiranjay Mukhopadhyay2
Journal of Preventive Medicine and Public Health 2016;49(3):165-175.
Published online: May 31, 2016
  • 363 Download
  • 63 Crossref
  • 73 Scopus

1Directorate of Research (Health Sciences), Manipal University, Manipal, India

2Department of Microbiology, Kasturba Medical College, Manipal University, Manipal, India

3Department of Obstetrics and Gynecology, Melaka Manipal Medical College, Manipal University, Manipal, India

4Department of Community Dentistry, Manipal College of Dental Sciences, Manipal University, Manipal, India

5Department of Community Medicine, Kasturba Medical College, Manipal University, Manipal, India

Corresponding author: Vandana Kalwaje Eshwara, MD  Manipal, Karnataka 576104, India  Tel: +91-820-2923171, Fax: +91-820-2593214 E-mail:
• Received: February 22, 2016   • Accepted: May 19, 2016

Copyright © 2016 The Korean Society for Preventive Medicine

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

  • Objectives:
    The present study was undertaken to study the maternal risk factors for preterm birth (PTB) and low birth weight (LBW) with a special emphasis on assessing the proportions of maternal genitourinary and periodontal infections among Indian women and their association with adverse pregnancy outcomes.
  • Methods:
    A hospital-based prospective study comprising 790 pregnant women visiting the obstetrics clinic for a routine antenatal check-up was undertaken. Once recruited, all study participants underwent clinical and microbiological investigations for genitourinary infections followed by a dental check-up for the presence of periodontitis. The study participants were followed up until their delivery to record the pregnancy outcomes. Infectious and non-infectious risk factors for PTB and LBW were assessed using univariate and multivariate Cox regression analysis. Independent risk factors for PTB and LBW were reported in terms of adjusted relative risk (ARR) with the 95% confidence interval (CI).
  • Results:
    Rates of PTB and LBW in the study population were 7.6% and 11.4%, respectively. Previous preterm delivery (ARR, 5.37; 95% CI, 1.5 to 19.1), periodontitis (ARR, 2.39; 95% CI, 1.1 to 4.9), Oligohydramnios (ARR, 5.23; 95% CI, 2.4 to 11.5), presence of Nugent’s intermediate vaginal flora (ARR, 2.75; 95% CI, 1.4 to 5.1), gestational diabetes mellitus (ARR, 2.91; 95% CI, 1.0 to 8.3), and maternal height <1.50 m (ARR, 2.21; 95% CI, 1.1 to 4.1) were risk factors for PTB, while periodontitis (ARR, 3.38; 95% CI, 1.6 to 6.9), gestational hypertension (ARR, 3.70; 95% CI, 1.3 to 10.8), maternal height <1.50 m (ARR, 2.66; 95% CI, 1.3 to 5.1) and genital infection during later stages of pregnancy (ARR, 2.79; 95% CI, 1.2 to 6.1) were independent risk factors for LBW.
  • Conclusions:
    Our study findings underscore the need to consider screening for potential genitourinary and periodontal infections during routine antenatal care in developing countries.
Preterm birth (PTB) is an obstetric complication of complex etiology associated with significant neonatal mortality and morbidity worldwide. Numerous morbidities among infants born preterm have been reported to lead to both neonatal mortality and late sequelae such as respiratory distress syndrome, retinopathy of prematurity, neurological and neuro-developmental abnormalities, and lifelong vision and hearing impairment [1]. Globally, more than 20 million infants are born every year with a birth weight less than 2500 g, with Asia and Africa witnessing the largest numbers. India alone accounts for 40% of the cases of low birth weight (LBW) in the developing world, and more than half of those in Asia [2]. Various maternal demographic, behavioral, and clinical characteristics have been associated with PTB including maternal race/ethnicity, maternal age at either extreme, cigarette smoking, low pre-pregnancy weight, psychosocial stress, previous PTB, and maternal intrauterine infections [3]. An association of bacterial vaginosis (BV) and periodontitis with adverse pregnancy outcomes has been reported among women belonging to various ethnic groups and geographical locations [4-7]. Despite substantial evidence suggesting the positive association of these infections with adverse pregnancy outcomes from elsewhere, routine screening of pregnant women for genital and periodontal infections is not a common practice in developing countries such as India. Considering the overall paucity of information regarding the risk factors for adverse pregnancy outcomes among Indian women, we undertook the present study to assess the magnitude of maternal infectious and non-infectious parameters and their association with PTB and LBW among a cohort of pregnant women.
Study Site, Design, and Population
A prospective cohort study was carried out at a secondary care hospital in South India for a period of three years (May 2011 to April 2014). The study was approved by the institutional ethics committee of Kasturba Hospital, Manipal (no. IEC160/2010). Pregnant women aged 18 to 35 years and with a gestational age of 8 to 24 weeks visiting the Obstetrics Clinic for a routine antenatal check-up were invited to participate in the study. Pregnant women with medical diseases such as diabetes mellitus, hypertension, hypo/hyperthyroidism; obstetrical complications such as placenta previa, cervical cerclage, uterine fibroids, twin pregnancy; lifestyle habits such as smoking and consumption of alcohol; or infections such as HIV and syphilis were not included in the study. The sample size was calculated anticipating a prevalence of lower genital infections and periodontitis among 30% of the study population, a 10% prevalence of PTB and a relative precision of 25%. It was estimated that a sample of 756 women was needed to show a statistically significant association of maternal genitourinary tract and periodontal infections with PTB and LBW among the target study population.
After written informed consent for study enrollment had been obtained, structured interviews were carried out to gather data regarding socioeconomic, demographic, relevant medical, and obstetric history. Gestational age was estimated based on the date of the last menstrual period, followed by a confirmation using ultrasonography. The body mass index (BMI) of the study participants was calculated based on their weight (kg) and height (m) recorded during the study recruitment. Based on their BMI, women were classified as underweight (BMI ≤19.9 kg/m2), normal weight (20.0-24.9 kg/m2), overweight (25.0-29.9 kg/m2), and obese (≥30.0 kg/m2).
Testing for Genitourinary and Periodontal Infections
A clean catch mid-stream urine specimen was collected from each study participant during recruitment. Urine specimens were subjected to semi-quantitative microbiological culture using cysteine lactose electrolyte-deficient media. Bacterial isolates with significant counts (>105 CFU/mL) were identified up to the species level and antimicrobial susceptibility testing for the isolates was tested and reported as per the Clinical and Laboratory Standards Institute guidelines. Women diagnosed with urinary tract infections (UTI) and/or asymptomatic bacteriuria (AB) were treated with a pathogen-specific antimicrobial agent. All the study participants underwent per speculum examination, during which high vaginal and endocervical swabs were collected for the microbiological diagnosis of lower genital tract infections such as BV, vulvovaginal candidiasis (VVC), trichomoniasis, and genital chlamydiasis. Diagnosis of BV was made by examination of Gram-stained high vaginal smears using Nugent’s scoring system (NSS) [8]. Other forms of vaginitis were diagnosed using a wet mount examination of the vaginal secretions for trichomoniasis and Gram-stained smear examination of the high vaginal swabs for VVC. Decisions regarding the treatment for vaginal infections and the choice of an antimicrobial agent for treatment was made by the obstetrician based on the clinical examination alone in the present study. DNA from the endocervical swab was extracted using a QIAamp DNA mini kit (Qiagen GmbH, Hilden, Germany) as per the manufacturer’s instructions. The extracted DNA was used for detection of Chlamydia trachomatis. The oligonucleotide primers and the polymerase chain reaction mixture and conditions used in our study targeted the detection of a 201-bp region of the cryptic plasmid of C. trachomatis as described previously [9]. A detailed periodontal examination was performed using the Community Periodontal Index (CPI) scoring system at the time of recruitment. A pathological pocket depth of at least 4 mm (CPI score ≥3) among any one of the six index teeth examined was diagnostic for periodontitis [10]. Women diagnosed with periodontitis were not provided any form of treatment (antibiotics or scaling) in the present study.
Follow-up of Study Participants and Pregnancy Outcomes
Study participants were followed for the rest of their gestational period, and the occurrence of any adverse event(s) such as late pregnancy loss between 20 weeks and 24 weeks of gestation, gestational diabetes, gestational hypertension, intrauterine growth restriction, threatened preterm labor, UTI, symptomatic genital infections during later stages of pregnancy, and oligohydroamnios were recorded. PTB was considered to be any birth occurring before the completion of 37 weeks of gestation. LBW was considered to be a birth weight of less than 2500 g. Infants born preterm with LBW were considered to be preterm low birth weight (PLBW). For the final analysis to assess the risk factors for PTB, PLBW, and LBW among the study population, data regarding the infectious and non-infectious parameters of 710 women was included.
Statistical Analysis
Subject information was digitized and analyzed using the SPSS version 16.0 (SPSS South Asia Pvt. Ltd., Bangalore, India). The proportion of cases with maternal genitourinary and periodontal infections were estimated using descriptive statistics. The incidence density per 1000 person-weeks of gestation for PTB and LBW were estimated among the present study cohort. The chi-square test was used for the comparison of baseline and infectious parameters among the members of the study population with follow-up data available and those that were lost during follow-up. The association of infectious and non-infectious maternal parameters with adverse pregnancy outcomes was estimated in terms of crude relative risk (CRR) with a 95% confidence interval (CI) using univariate Cox regression. Using forward Wald multivariate Cox regression, risk factors for PTB, PLBW, and LBW were assessed separately after adjusting for the maternal baseline, physical, and infectious covariates. Ultimately, independent risk factors with adjusted relative risk (ARR) and 95 % CI were reported.
A total of 790 women were recruited for the study. The mean age of the study population was 27.18±3.54 years. The mean gestational age of the study population at inclusion was 14±4.2 weeks. The majority of the study subjects completed at least 12 years of schooling (n=518, 65%) and 69% (n=550) of them had a monthly household income of >10 000 Indian rupees (INR). The mean height of the study population was 1.55±0.05 m (range, 1.35 to 1.72 m). The majority (n=506, 64%) of the study participants had a normal BMI. Slightly more than half (n=461, 58%) of the study participants were primi gravida. Among the 329 women who had had a previous pregnancy, 110 (33.4%) reported a history of abortion. Prior history of preterm delivery was reported among 10/219 (4.5%) of the women. A detailed description of the baseline characteristics among the study population is presented in Table 1.
Using NSS, BV (Nugent’s score, 7 to 10) was diagnosed among 48 (6%) of the women. Further, 108 (13.6%) women were found to have intermediate vaginal flora (Nugent’s score, 4 to 6). VVC and trichomoniasis were observed among 97 (12.2%) and 94 (11.8%) women, respectively. None of the women tested were positive for C. trachomatis. Significant bacteriuria was observed in 57 (7.2%) women. Of these 57 women, AB was observed among 20 (35%) and the other 37 (65%) women had clinical symptoms of UTI. Among women with significant bacteriuria, Escherichia coli was the leading pathogen, in 42 (75%) of the cases, followed by Klebsiella pneumoniae in nine (16%). From the other five women, Enterococcus spp. was isolated in four (7%) and Proteus mirabilis in one (2%). Nitrofurantoin (52%) and cefixime (45%) were the most commonly prescribed antibiotics for treatment of significant bacteriuria. Overall, the proportion of women with AB in the present study population was 2.5% at the time of testing. Periodontitis was diagnosed in 90 (11.3%) women using CPI scoring. The proportion of maternal genitourinary and periodontal infections among the study population is detailed in Table 1.
Pregnancy outcomes for 64 (8%) women were not available for the final analysis, as these women were lost to follow-up during the study. A detailed description of the study participants that were lost during follow-up is provided in Table 1. Among the 726 women with follow-up data available, adverse events such as late pregnancy loss (n=16, 2.2%), gestational diabetes mellitus (n=38, 5.2%), gestational hypertension (n=22, 3%), UTI (n=23, 3.1%), symptomatic genital infections during the later stages of pregnancy (n=65, 8.9%), and oligohydramnios (n=31, 4.2%) were observed. Among the 710 women with a successful pregnancy, 54 (7.6%) women experienced preterm delivery. The mean gestational age of the women that delivered at term and preterm in the present study were 38.5±0.8 and 35.6±2.3 weeks, respectively. LBW was observed among 81 (11.4%) babies born in the study. The mean birth weight of the babies born was 2971±438.75 g. Among the 81 infants born with LBW, 34 (42%) of them were born preterm, and intrauterine growth restriction was observed in 11 (13.5%). Overall, the incidence densities of PTB and LBW among the study population were 3.2 (95% CI, 2.8 to 3.5) and 4.9 (95% CI, 4.6 to 5.2) per 1000 person-weeks of gestation, respectively.
Further, presence of more than one of the three infections, namely, periodontitis, BV, and intermediate vaginal flora, was observed in 34/710 (4.7%) women. Preterm delivery and LBW were observed among 23.5% (n=8) and 35.2% (n=12), respectively, of the 34 women with more than one infection (p < 0.001), as compared to 10.4% (n=15) and 15.2% (n=22) of the 144 women with only one of the three infections. Using univariate Cox regression, we observed a significant association of maternal height less than 1.50 m, history of previous preterm delivery, gestational hypertension, oligohydramnios, BV, and periodontitis with PTB and/or LBW. Other maternal baseline characteristics such as BMI, level of education, monthly household income, and parity index did not have an association with adverse pregnancy outcomes. A detailed description of the association of maternal physical, demographic, and infectious parameters with PTB, PLBW, and LBW among the study population is provided in Table 2.
Independent risk factors for PTB in the present study population were previous preterm delivery (ARR, 5.37; 95% CI, 1.5 to 19.1), periodontitis (ARR, 2.39; 95% CI, 1.1 to 4.9), Oligohydramnios (ARR, 5.23; 95% CI, 2.4 to 11.5), presence of Nugent’s intermediate vaginal flora (ARR, 2.75; 95% CI, 1.4 to 5.1), gestational diabetes mellitus (ARR, 2.91; 95% CI, 1.0 to 8.3), and maternal height <1.50 m (ARR, 2.21; 95% CI, 1.1 to 4.1). Similarly, independent risk factors for LBW were periodontitis (ARR, 3.38; 95% CI, 1.6 to 6.9), gestational hypertension (ARR, 3.70; 95% CI, 1.3 to 10.8), maternal height <1.50 m (ARR, 2.66; 95% CI, 1.3 to 5.1), and genital infections during the later stages of pregnancy (ARR, 2.79; 95% CI, 1.2 to 6.1). Independent risk factors for PTB, PLBW, and LBW in the study population are presented in Table 3.
PTB is a prevalent obstetric complication associated with significant neonatal mortality and morbidity worldwide. Addressing the burden of PTB in developing countries is of public health importance due to its high (9 to 16%) prevalence. Though the exact etiopathogenesis of PTB is still unclear, in developing nations, prediction and/or diagnosis of this multifactorial process is made mainly based on the evidence reported in the western literature on the risk factors and probable pathological mechanisms [3,11,12]. More recently, reports suggesting the disparity in risk factors for PTB due to ethnic/racial influences among women underscored the need for assessing the risk factors at both inter-national and intra-national levels to formulate interventions to reduce the burden of PTB. Given this context, the present study was undertaken to elucidate the infectious and non-infectious risk factors for PTB and LBW among Indian pregnant women seeking routine antenatal care at a secondary care hospital.
The PTB rate of 7.6% observed in the present study population is lower as compared to the estimates (15%) reported by the World Health Organization among Indian women [13]. Similarly, we observed a lower rate (11.4%) of LBW in our study population as compared to previous reports from other parts of the country [14,15]. The low rates of PTB and LBW in the present study as compared to the previous reports from other parts of the country could be attributed to the target study population for the following reasons: i) The present study was carried out in Udupi district, which is considered to be one of the more developed districts in the state of Karnataka, India [16]. ii) The study population consisted of young women (mean age, 27.18±3.5 years) with higher levels of education. iii) The majority of the study participants belonged to the middle income group (>10 000 INR/mo), unlike the other studies, which had higher rates of PTB and LBW among women belonging to the low income group and those with lower literacy [13-15]. iv) Further, to avoid the confounding effect of other known risk factors for PTB, in the present study we excluded the recruitment of women with a history of smoking, consumption of alcohol, twin and multiple pregnancy, pre-gestational diabetes mellitus, and hypertension.
While PTB is well acknowledged as a multifactorial process, ascending genital tract infections have previously been implicated in at least half of the cases. In particular, the causal relationship between BV and PTB among women from various ethnic groups has been consistently noted. A few studies have reported the magnitude of BV during pregnancy among Indian women (6.4% [17], 24.3% [18], and 12% [19]); however, the paucity of data regarding the potential association of BV with PTB among these women is evident in the published literature. A lower rate of BV (6%) could possibly be attributed to the socioeconomic and lifestyle factors of our study population. BV was reported to be high among women from low socioeconomic strata, and those with low levels of education, a history of smoking, and multiple sex partners [20-22], while our study population not fit this description. Further, none of the previously reported studies from India could be matched with our cohort in terms of the sample size and gestational age at the time of testing. With the overall low proportion of women with BV (48/790, 6%) and further loss of six women diagnosed with BV on follow-up, the present study had relatively a small cohort of 42 women with BV for the final outcome analysis. In this context, the finding of BV not being an independent risk factor for PTB and LBW in the present study population is not surprising. Nevertheless, a positive association of BV with PTB as observed using univariate Cox regression in the present study population underscores the need for future studies using a larger sample size to understand the causal relationship in Indian women.
Other forms of vaginal infection like VVC and trichomoniasis were more commonly observed than BV in the present study. However, neither VVC nor trichomoniasis had any statistically significant association with PTB or LBW among the women in this study. These findings are similar to those reported previously among women belonging to other ethnic groups [23,24]. The causal relationship between intermediate vaginal flora and adverse pregnancy outcomes has been increasingly emphasized in the past two decades [25,26]. While the exact mechanism by which the presence of these intermediate vaginal flora could lead to PTB is unknown, inflammatory responses primarily due to the abundance of IL1 and IL6 were reported to mediate the production of prostaglandins and cause preterm uterine contractions [27]. In the present cohort, women with Nugent’s intermediate vaginal flora were found to be at 2.7 times greater risk for preterm delivery than women with normal vaginal flora. To the best of our knowledge, this is the first report suggesting a positive association of intermediate vaginal flora in pregnant Indian women with PTB and PTLBW.
Of the total of 57 (7.1%) women diagnosed with AB and UTI during their first visit, 55 (97%) of them received specific antibiotic therapy, and none of them developed complications like pyelonephritis. Previously from a meta-analysis, it was reported that treatment of AB and UTI among pregnant women was a useful intervention to avoid complications like pyelonephritis and its associated adverse pregnancy outcomes like PTB and LBW [28]. From a prospective study among North Indian pregnant women, no association between AB diagnosed early during pregnancy and adverse pregnancy outcomes was reported [29]. We attribute the lack of association of AB and UTI with PTB and LBW in the present study to early diagnosis and effective antibiotic treatment. Based on the current study’s findings, we recommend the routine screening of pregnant women for the presence of AB during their early pregnancies as a cost-effective intervention to avoid further complications.
The proportion of periodontitis in the present study’s population (11.6%) is slightly lower than the overall prevalence (14% to 18%) of the disease reported in the adult population of India [30]. This is likely due to our study population comprising women in younger age groups from the middle and upper middle income category, and non-smokers [31,32]. Previously, a decrease in the incidence of PTB was reported among Indian pregnant women who underwent treatment for periodontitis [7]. However, considering the significance of periodontitis as an independent risk factor for both PTB and LBW, as observed in the present study, we emphasize the need for further studies to determine whether early diagnosis and treatment (<20 weeks of gestation) of these subtle infections can show a reduction in rates of PTB and LBW.
While women with pre-gestational hypertension were excluded from recruitment in the present study, 22 (3%) of the 726 women developed gestational hypertension (after 20 weeks of gestation), which was found to be an independent risk factor for PTB and LBW. A similar association of gestational hypertension was reported among various study populations globally [1,12,33]. Oligohydramnios (amniotic fluid index <5 cm) during the third trimester of pregnancy was diagnosed in 31 (4.3%) of the women. A similar association of oligohydramnios with adverse pregnancy outcomes as observed in our study was reported previously [11,34]. A positive association of genital infections (diagnosed based on clinical signs and symptoms alone in the present study) during later stages of pregnancy with LBW suggests the need for future longitudinal studies to assess the implications of changes in the vaginal microbioma during different stages of pregnancy for adverse pregnancy outcomes.
We acknowledge a few limitations of our study. The rate of infections reported in our study represented the proportion of women infected during their early stages of pregnancy only. Considering the homogenous nature of our study population and variation in the rates of these infections due to the socioeconomic and behavioral characteristics of the study population, the rates of infections reported in the present study cannot be generalized to pregnant women with diverse demographic characteristics. The attrition rate of 8% in the study population was also one of our limitations. However, the study findings deduced from women with follow-up data available can be extrapolated to those that were lost to follow-up, as the two groups did not differ significantly in terms of their baseline characteristics and infectious parameters. Screening for the presence of genitourinary and periodontal infections could not be repeated during the later stages of pregnancy in the present study due to resource constraints. If only this could be done, we could have estimated the proportion of women developing new or recurrent infections during the later stages of pregnancy. Despite these limitations, our study findings add significant insight on the role of asymptomatic maternal infections such as intermediate vaginal flora and periodontitis on adverse pregnancy outcomes. These findings have important implications for settings where infection screening is not a routine practice during antenatal care.
This study was supported by an Ad-hoc Research Grant (no. 2009-03350) from the Indian Council of Medical Research, New Delhi, India.


The authors have no conflicts of interest associated with the material presented in this paper.

Table 1.
Comparison of baseline characteristics between study participants with follow-up loss and follow-up completion (n=790)
Baseline characteristics Proportion Follow-up completed (n=726) Follow-up lost (n=64) p-value
 Hindu 694 (87.8) 639 (88.0) 55 (85.9) 0.27
 Christian 62 (7.8) 55 (7.5) 7 (10.9)
 Muslim 34 (4.3) 32 (4.4) 2 (3.1)
 Homemaker 651 (82.4) 603 (83.0) 48 (75.0) 0.13
 Working 139 (17.5) 123 (16.9) 16 (25.0)
Monthly income (INR)
 <5000 41 (5.1) 34 (4.6) 7 (10.9) 0.60
 5001-10 000 199 (25.1) 187 (25.7) 12 (18.7)
 10 001-15 000 166 (21.0) 154 (21.2) 12 (18.7)
 >15 000 384 (48.6) 351 (48.3) 33 (51.5)
Level of education
 <7 years of schooling 272 (34.4) 245 (33.7) 27 (42.0) 0.49
 7-12 years of schooling 330 (41.7) 309 (42.5) 21 (34.0)
 High school graduate & above 188 (23.7) 172 (23.6) 16 (24.0)
Parity index
 Primigravida 461 (58.3) 422 (58.1) 39 (60.9) 0.87
 Second gravida 261 (33.0) 243 (33.4) 18 (28.1)
 Third gravida 68 (8.6) 61 (8.4) 7 (11.0)
Maternal age (y)
 20-24 194 (24.5) 177 (24.3) 17 (26.5) 0.38
 25-29 395 (50.0) 369 (50.8) 26 (40.6)
 30-35 201 (25.5) 180 (24.7) 21 (32.8)
Maternal height (m)
 <1.50 146 (18.4) 130 (17.9) 16 (25.0) 0.12
 ≥1.50 644 (81.5) 596 (82.0) 48 (75.0)
Maternal BMI at first visit
 Normal 506 (64.0) 471 (64.8) 35 (54.6) 0.08
 Underweight 197 (25.0) 178 (24.5) 19 (29.6)
 Overweight 78 (9.8) 70 (9.6) 8 (12.5)
 Obese 9 (1.1) 7 (0.9) 2 (3.1)
Bacterial vaginosis
 Present 48 (6.0) 42 (5.7) 6 (9.3) 0.17
 Absent 742 (94.0) 684 (94.3) 58 (90.6)
Vulvovaginal candidiasis
 Present 97 (12.2) 86 (11.8) 11 (17.1) 0.33
 Absent 693 (87.8) 640 (88.2) 53 (82.8)
 Present 94 (11.8) 86 (11.8) 8 (12.5) 1.00
 Absent 696 (88.2) 640 (88.2) 56 (87.5)
Nugent’s grade II flora
 Present 108 (13.6) 101 (13.9) 7 (10.9) 0.57
 Absent 682 (86.3) 625 (86.0) 57 (89.0)
Urinary tract infection
 Present 57 (7.2) 50 (6.8) 7 (10.9) 0.31
 Absent 733 (92.8) 676 (93.2) 57 (89.0)
 Present 90 (11.3) 83 (11.4) 7 (10.9) 0.22
 Absent 700 (88.6) 643 (88.5) 57 (89.0)

Values are presented as number (%).

INR, Indian rupees; BMI, body mass index.

Table 2.
Association of maternal physical, demographic, and infectious parameters with PTB, PLBW, and LBW in the study population (n=710)
Variable n (%) PTB
n (%) CRR (95% CI) n (%) CRR (95% CI) n (%) CRR (95% CI)
Total 54 (7.6) 34 (4.7) 47 (6.6)
 Hindu 630 (88.7) 49 (7.8) 1.0 (reference) 30 (4.7) 1.0 (reference) 43 (6.8) 1.0 (reference)
 Christian 52 (7.3) 5 (9.6) 0.9 (0.26, 3.12) 4 (7.6) 1.9 (0.68, 5.53) 3 (5.7) 1.0 (0.24, 4.75)
 Muslim 28 (3.9) 0 (0.0) - 0 (0.0) - 1 (3.1) 0.3 (0.04, 2.26)
p-value 0.27 0.38 0.27
 Homemaker 591 (83.3) 46 (7.5) 1.0 (reference) 28 (4.7) 1.0 (reference) 41 (6.9) 1.0 (reference)
 Working 119 (16.7) 8 (6.7) 0.9 (0.40, 1.90) 6 (5.0) 0.4 (0.15, 1.53) 6 (5.0) 0.5 (0.22, 1.50)
p-value 0.66 0.37 0.31
Monthly income (INR)
 <5000 33 (4.6) 2 (6.1) 1.0 (reference) 1 (3.0) 1.0 (reference) 3 (9.0) 1.0 (reference)
 5001-10 000 181 (25.5) 10 (5.3) 1.1 (0.25, 5.33) 7 (3.8) 0.3 (0.04, 2.83) 16 (8.8) 0.9 (0.26, 3.54)
 10 001-15 000 145 (20.4) 14 (9.6) 2.2 (0.49, 9.90) 8 (5.5) 0.7 (0.32, 1.90) 11 (7.6) 0.9 (0.24, 3.57)
 >15 001 351 (49.4) 28 (8.0) 1.7 (0.41, 7.44) 18 (5.1) 0.7 (0.26, 2.00) 17 (4.9) 0.4 (0.12, 1.73)
p-value 0.43 0.57 0.18
Level of education
 <7 years of schooling 240 (33.8) 22 (9.1) 1.0 (reference) 15 (6.2) 1.0 (reference) 19 (7.9) 1.0 (reference)
 7-12 years of schooling 301 (42.4) 22 (7.3) 1.6 (0.77, 3.46) 12 (3.9) 1.5 (0.63, 3.83) 18 (5.9) 1.5 (0.71, 3.48)
 High school graduate & above 169 (23.8) 10 (5.9) 1.1 (0.51, 2.37) 7 (4.1) 0.7 (0.29, 2.03) 10 (5.9) 1.2 (0.56, 2.80)
p-value 0.17 0.21 0.39
 Spontaneous1 695 (97.9) 52 (7.4) 1.0 (reference) 32 (4.6) 1.0 (reference) 46 (6.6) 1.0 (reference)
 Infertility workup 15 (2.1) 2 (13.3) 0.4 (0.10, 1.97) 2 (13.3) 0.2 (0.06, 1.27) 1 (6.6) 1.1 (0.14, 8.77)
p-value 0.42 0.30 0.61
Parity index
 Primigravida 419 (59.0) 32 (7.6) 1.0 (reference) 18 (4.3) 1.0 (reference) 30 (7.2) 1.0 (reference)
 Second gravida 232 (32.7) 14 (6.1) 0.5 (0.21, 1.30) 10 (4.3) 0.5 (0.20, 1.66) 14 (6.0) 1.8 (0.43, 8.11)
 Third gravida 59 (8.3) 8 (14.0) 0.3 (0.12, 0.85) 6 (10.0) 0.3 (0.13, 1.07) 3 (5.1) 1.5 (0.33, 6.98)
p-value 0.10 0.17 0.33
Maternal age (y)
 20-24 177 (24.9) 19 (10.9) 1.0 (reference) 9 (5.0) 1.0 (reference) 17 (9.6) 1.0 (reference)
 25-29 354 (49.8) 21 (5.9) 1.5 (0.68, 3.55) 12 (3.3) 0.6 (0.25, 1.67) 20 (5.6) 2.0 (0.87, 4.69)
 30-35 179 (25.2) 14 (7.8) 0.7 (0.35, 1.67) 13 (7.3) 0.3 (0.15, 0.93) 10 (5.6) 1.0 (0.46, 2.37)
p-value 0.24 0.42 0.09
Maternal BMI at first visit
 Normal 457 (64.3) 31 (6.7) 1.0 (reference) 19 (4.1) 1.0 (reference) 25 (5.4) 1.0 (reference)
 Underweight 177 (24.9) 14 (7.9) 0.2 (0.04, 1.00) 9 (5.0) 0.2 (0.03, 2.28) 16 (9.0) 0.6 (0.32, 1.18)
 Overweight 70 (9.8) 7 (10.0) 0.1 (0.04, 0.80) 5 (7.1) 0.2 (0.02, 1.85) 6 (8.5) 1.2 (0.47, 3.11)
 Obese 6 (0.8) 2 (33.3) 0.3 (0.07, 1.80) 1 (16.6) 0.3 (0.30, 3.17) 0 (0.0) -
p-value 0.10 0.26 0.27
Previous PTB
 Yes 8 (1.1) 3 (37.5) 6.3 (1.96, 20.36) 3 (37.5) 12.9 (2.81, 59.86) 1 (12.5) 3.2 (0.35, 29.52)
 No 702 (98.9) 51 (7.2) 1.0 (reference) 31 (4.4) 1.0 (reference) 46 (6.5) 1.0 (reference)
p-value 0.002 0.001 0.31
Maternal height (m)
 <1.50 126 (17.7) 17 (13.5) 2.0 (1.11, 3.60) 14 (11.1) 2.6 (1.25, 5.32) 17 (13.4) 2.8 (1.40, 5.43)
 ≥1.50 584 (82.3) 37 (6.3) 1.0 (reference) 20 (3.4) 1.0 (reference) 30 (5.1) 1.0 (reference)
p-value 0.02 0.01 0.003
Bacterial vaginosis
 Present 42 (5.9) 7 (16.7) 3.2 (1.02, 10.41) 6 (14.2) 1.8 (0.60, 5.37) 5 (11.9) 1.4 (0.53, 4.16)
 Absent 668 (94.1) 47 (7.0) 1.0 (reference) 28 (4.1) 1.0 (reference) 42 (6.2) 1.0 (reference)
p-value 0.05 0.06 0.17
 Present 84 (11.8) 7 (8.3) 0.8 (0.34, 2.08) 4 (4.7) 0.7 (0.24, 2.27) 6 (7.1) 0.8 (0.34, 2.16)
 Absent 626 (88.2) 47 (7.5) 1.0 (reference) 30 (4.7) 1.0 (reference) 41 (6.5) 1.0 (reference)
p-value 0.71 0.92 0.81
 Present 84 (11.8) 5 (5.9) 0.3 (0.08, 1.57) 3 (3.5) 0.9 (0.28, 3.22) 3 (3.5) 0.3 (0.08, 1.56)
 Absent 626 (88.2) 49 (7.8) 1.0 (reference) 31 (4.9) 1.0 (reference) 44 (7.0) 1.0 (reference)
p-value 0.18 0.41 0.35
Nugent’s grade II flora
 Present 78 (11.0) 13 (16.6) 1.1 (0.45, 2.81) 11 (14.0) 0.4 (0.17, 1.10) 7 (8.9) 0.9 (0.40, 2.44)
 Absent 632 (89.0) 41 (6.5) 1.0 (reference) 23 (3.6) 1.0 (reference) 40 (6.3) 1.0 (reference)
p-value 0.78 0.006 0.66
Urinary tract infection
 Present 48 (6.8) 3 (6.2) 1.2 (0.39, 4.18) 3 (6.2) 1.5 (0.47, 5.30) 3 (6.2) 0.8 (0.38, 4.16)
 Absent 662 (93.2) 51 (7.7) 1.0 (reference) 31 (4.6) 1.0 (reference) 44 (6.6) 1.0 (reference)
p-value 0.68 0.69 0.87
 Present 81 (11.4) 11 (13.5) 3.4 (1.73, 6.93) 8 (9.8) 2.8 (1.26, 6.49) 12 (14.8) 3.4 (1.71, 6.80)
 Absent 629 (88.6) 43 (6.8) 1.0 (reference) 24 (3.8) 1.0 (reference) 35 (5.5) 1.0 (reference)
p-value <0.001 0.001 0.003
Gestational hypertension
 Present 22 (3.0) 6 (11.1) 3.3 (1.15, 9.56) 3 (13.6) 3.5 (1.52, 8.44) 4 (18.1) 3.0 (1.28, 7.07)
 Absent 688 (97.0) 49 (7.1) 1.0 (reference) 31 (4.5) 1.0 (reference) 43 (6.2) 1.0 (reference)
p-value 0.02 0.001 0.02
 Present 31 (4.3) 8 (25.8) 4.8 (2.24, 10.63) 7 (22.5) 2.7 (1.07, 6.93) 4 (12.9) 5.6 (2.91, 10.84)
 Absent 679 (95.6) 46 (6.7) 1.0 (reference) 27 (3.9) 1.0 (reference) 43 (6.3) 1.0 (reference)
p-value <0.001 <0.001 0.05
Gestational diabetes mellitus
 Present 38 (5.3) 4 (10.5) 1.9 (0.67, 5.59) 3 (7.9) 1.2 (0.37, 3.93) 2 (5.2) 1.7 (0.69, 4.42)
 Absent 672 (94.6) 50 (7.4) 1.0 (reference) 31 (4.6) 1.0 (reference) 45 (6.6) 1.0 (reference)
p-value 0.34 0.47 1.00
UTI during follow-up
 Present 23 (3.1) 3 (13.0) 1.2 (0.38, 4.25) 1 (4.3) 0.6 (0.15, 2.75) 0 (0.0) 0.2 (0.30, 1.76)
 Absent 687 (96.9) 51 (7.4) 1.0 (reference) 33 (4.8) 1.0 (reference) 47 (6.8) 1.0 (reference)
p-value 0.41 0.87 0.39
GI during follow-up
 Present 65 (9.1) 6 (9.2) 1.3 (0.55, 3.13) 2 (3.0) 0.7 (0.17, 3.13) 9 (13.8) 2.0 (1.05, 3.81)
 Absent 645 (90.8) 48 (7.4) 1.0 (reference) 32 (4.9) 1.0 (reference) 38 (5.8) 1.0 (reference)
p-value 0.45 0.13 0.01

The CRR was determined using Cox regression analysis.

PTB, preterm birth; PTLBW, preterm low birth weight; LBW, low birth weight; CRR, crude relative risk; CI, confidence interval; INR, Indian rupees; BMI, body mass index; VVC, vulvovaginal candidiasis; UTI, urinary tract infection; GI, genital infection.

Table 3.
Independent risk factors for PTB, PTLBW, and LBW in the study population
Risk factors PTB PTLBW LBW
Previous preterm delivery 5.37 (1.5, 19.1) - -
p-value 0.009
Periodontitis 2.39 (1.1, 4.9) 3.29 (1.8, 5.7) 3.38 (1.6, 6.9)
p-value 0.02 <0.001 0.001
Oligohydramnios 5.23 (2.4, 11.5) 4.67 (2.3, 9.3) -
p-value <0.001 <0.001
Nugent’s intermediate vaginal flora 2.75 (1.4, 5.1) 2.19 (1.3, 3.7) -
p-value 0.002 0.005
Gestational diabetes mellitus 2.91 (1.0, 8.3) - -
p-value 0.05
Maternal height (<1.50 m) 2.21 (1.1, 4.1) 3.10 (1.8, 5.1) 2.66 (1.3, 5.1)
p-value 0.01 <0.001 0.004
Gestational hypertension - 2.90 (1.1, 7.3) 3.70 (1.3, 10.8)
p-value 0.02 0.01
Genital infection during later stages of pregnancy - - 2.79 (1.2, 6.1)
p-value 0.01

Value are presented as adjusted relative risk (95% confidence interval). The relative risk was calculated using the Cox proportional hazard model and estimated after adjusting for age, level of education, parity, monthly household income, and maternal body mass index in the study population.

PTB, preterm birth; PTLBW, preterm low birth weight; LBW, low birth weight.

  • 1. Blencowe H, Cousens S, Chou D, Oestergaard M, Say L, Moller AB, et al. Born too soon: the global epidemiology of 15 million preterm births. Reprod Health 2013;10 Suppl 1: S2Article
  • 2. United Nations Children’s Fund; World Health Organization. Low birthweight: country, regional and global estimates. 2004 [cited 2016 May 28]. Available from:
  • 3. Chan RL. Biochemical markers of spontaneous preterm birth in asymptomatic women. Biomed Res Int 2014;2014: 164081ArticlePubMedPMCPDF
  • 4. Paige DM, Augustyn M, Adih WK, Witter F, Chang J. Bacterial vaginosis and preterm birth: a comprehensive review of the literature. J Nurse Midwifery 1998;43(2):83-89ArticlePubMed
  • 5. Svare JA, Schmidt H, Hansen BB, Lose G. Bacterial vaginosis in a cohort of Danish pregnant women: prevalence and relationship with preterm delivery, low birthweight and perinatal infections. BJOG 2006;113(12):1419-1425ArticlePubMed
  • 6. Offenbacher S, Boggess KA, Murtha AP, Jared HL, Lieff S, McKaig RG, et al. Progressive periodontal disease and risk of very preterm delivery. Obstet Gynecol 2006;107(1):29-36ArticlePubMed
  • 7. Tarannum F, Faizuddin M. Effect of periodontal therapy on pregnancy outcome in women affected by periodontitis. J Periodontol 2007;78(11):2095-2103ArticlePubMed
  • 8. Nugent RP, Krohn MA, Hillier SL. Reliability of diagnosing bacterial vaginosis is improved by a standardized method of gram stain interpretation. J Clin Microbiol 1991;29(2):297-301ArticlePubMedPMCPDF
  • 9. Mahony JB, Luinstra KE, Sellors JW, Jang D, Chernesky MA. Confirmatory polymerase chain reaction testing for Chlamydia trachomatis in first-void urine from asymptomatic and symptomatic men. J Clin Microbiol 1992;30(9):2241-2245ArticlePubMedPMCPDF
  • 10. World Health Organization. Oral health surveys: basic methods. 3rd ed. Geneva: World Health Organization; 1987
  • 11. Goldenberg RL, Goepfert AR, Ramsey PS. Biochemical markers for the prediction of preterm birth. Am J Obstet Gynecol 2005;192(5 Suppl):S36-S46ArticlePubMed
  • 12. Zhang YP, Liu XH, Gao SH, Wang JM, Gu YS, Zhang JY, et al. Risk factors for preterm birth in five Maternal and Child Health hospitals in Beijing. PLoS One 2012;7(12):e52780Article
  • 13. Vogel JP, Lee AC, Souza JP. Maternal morbidity and preterm birth in 22 low- and middle-income countries: a secondary analysis of the WHO Global Survey dataset. BMC Pregnancy Childbirth 2014;14: 56ArticlePubMedPMC
  • 14. Thomre PS, Borle AL, Naik JD, Rajderkar SS. Maternal risk factors determining birth weight of newborns: a tertiary care hospital based study. Int J Recent Trends Sci Technol 2012;5(1):3-8
  • 15. Mumbare SS, Maindarkar G, Darade R, Yenge S, Tolani MK, Patole K. Maternal risk factors associated with term low birth weight neonates: a matched-pair case control study. Indian Pediatr 2012;49(1):25-28ArticlePubMed
  • 16. Nair NS, Rao RS, Chandrashekar S, Acharya D, Bhat HV. Socio-demographic and maternal determinants of low birth weight: a multivariate approach. Indian J Pediatr 2000;67(1):9-14ArticlePubMed
  • 17. Balamurugan SS, Bendigeri N. Community-based study of reproductive tract infections among women of the reproductive age group in the urban health training centre area in hubli, karnataka. Indian J Community Med 2012;37(1):34-38ArticlePubMedPMC
  • 18. Laxmi U, Agrawal S, Raghunandan C, Randhawa VS, Saili A. Association of bacterial vaginosis with adverse fetomaternal outcome in women with spontaneous preterm labor: a prospective cohort study. J Matern Fetal Neonatal Med 2012;25(1):64-67ArticlePubMed
  • 19. Mittal V, Jain A, Pradeep Y. Development of modified diagnostic criteria for bacterial vaginosis at peripheral health centres in developing countries. J Infect Dev Ctries 2012;6(5):373-377ArticlePubMed
  • 20. Koumans EH, Sternberg M, Bruce C, McQuillan G, Kendrick J, Sutton M, et al. The prevalence of bacterial vaginosis in the United States, 2001-2004; associations with symptoms, sexual behaviors, and reproductive health. Sex Transm Dis 2007;34(11):864-869ArticlePubMed
  • 21. Larsson PG, Fåhraeus L, Carlsson B, Jakobsson T, Forsum U. Predisposing factors for bacterial vaginosis, treatment efficacy and pregnancy outcome among term deliveries; results from a preterm delivery study. BMC Womens Health 2007;7: 20ArticlePubMedPMC
  • 22. Misra DP, Trabert B. Vaginal douching and risk of preterm birth among African American women. Am J Obstet Gynecol 2007;196(2):140.e1-140.e8Article
  • 23. Klebanoff MA, Carey JC, Hauth JC, Hillier SL, Nugent RP, Thom EA, et al. Failure of metronidazole to prevent preterm delivery among pregnant women with asymptomatic Trichomonas vaginalis infection. N Engl J Med 2001;345(7):487-493ArticlePubMed
  • 24. Giraldo PC, Araújo ED, Junior JE, do Amaral RL, Passos MR, Gonçalves AK. The prevalence of urogenital infections in pregnant women experiencing preterm and full-term labor. Infect Dis Obstet Gynecol 2012;2012: 878241ArticlePubMedPMCPDF
  • 25. Carey JC, Klebanoff MA. Is a change in the vaginal flora associated with an increased risk of preterm birth? Am J Obstet Gynecol 2005;192(4):1341-1346ArticlePubMed
  • 26. Donders GG, Van Calsteren K, Bellen G, Reybrouck R, Van den Bosch T, Riphagen I, et al. Predictive value for preterm birth of abnormal vaginal flora, bacterial vaginosis and aerobic vaginitis during the first trimester of pregnancy. BJOG 2009;116(10):1315-1324ArticlePubMed
  • 27. Donati L, Di Vico A, Nucci M, Quagliozzi L, Spagnuolo T, Labianca A, et al. Vaginal microbial flora and outcome of pregnancy. Arch Gynecol Obstet 2010;281(4):589-600ArticlePubMed
  • 28. Smaill F, Vazquez JC. Antibiotics for asymptomatic bacteriuria in pregnancy. Cochrane Database Syst Rev 2007;(2):CD000490Article
  • 29. Jain V, Das V, Agarwal A, Pandey A. Asymptomatic bacteriuria & obstetric outcome following treatment in early versus late pregnancy in north Indian women. Indian J Med Res 2013;137(4):753-758PubMedPMC
  • 30. Murthy S, Mubashir A, Kodkany BS, Mallapur MD. Pregnancy periodontitis and low birth weight: a cohort study in rural Belgaum, India. Glob J Med Public Health 2012;1(4):42-48
  • 31. Kimura S, Ooshima T, Takiguchi M, Sasaki Y, Amano A, Morisaki I, et al. Periodontopathic bacterial infection in childhood. J Periodontol 2002;73(1):20-26ArticlePubMed
  • 32. Vogt M, Sallum AW, Cecatti JG, Morais SS. Factors associated with the prevalence of periodontal disease in low-risk pregnant women. Reprod Health 2012;9: 3ArticlePubMedPMC
  • 33. Yadav H, Lee N. Maternal factors in predicting low birth weight babies. Med J Malaysia 2013;68(1):44-47PubMed
  • 34. Kim BJ, Romero R, Mi Lee S, Park CW, Shin Park J, Jun JK, et al. Clinical significance of oligohydramnios in patients with preterm labor and intact membranes. J Perinat Med 2011;39(2):131-136ArticlePubMedPMC

Figure & Data



    Citations to this article as recorded by  
    • Associations of forms of intimate partner violence with low birth weight in India: findings from a population-based Survey
      Mostafizur Rahman, Helal Uddin, Lutfun Nahar Lata, Jalal Uddin
      The Journal of Maternal-Fetal & Neonatal Medicine.2024; 35(25): 7972.     CrossRef
    • Pregnancy Outcomes in Patients with Early-Onset Idiopathic Chronic Pancreatitis
      Gauri Kumbhar, Sudipta Dhar Chowdhury, Santosh Benjamin, Reuben Thomas Kurien, Ajith Thomas, Amit Dutta, Ebby George Simon, A. J. Joseph
      Digestive Diseases and Sciences.2024; 69(1): 256.     CrossRef
    • Prenatal influences on postnatal neuroplasticity: Integrating DOHaD and sensitive/critical period frameworks to understand biological embedding in early development
      Emma T. Margolis, Laurel J. Gabard‐Durnam
      Infancy.2024;[Epub]     CrossRef
    • National and regional prevalence of gestational diabetes mellitus in India: a systematic review and Meta-analysis
      Neha Mantri, Akhil Dhanesh Goel, Mamta Patel, Pritish Baskaran, Gitashree Dutta, Manoj Kumar Gupta, Vikas Yadav, Madhukar Mittal, Shashank Shekhar, Pankaj Bhardwaj
      BMC Public Health.2024;[Epub]     CrossRef
    • Maternal risk factors associated with term low birth weight in India: A review
      Harsh Vats, Ruchi Saxena, Mohinder P. Sachdeva, Gagandeep K. Walia, Vipin Gupta
      Anthropological Review.2023; 85(4): 61.     CrossRef
    • The bidirectional relationship between periodontal disease and pregnancy via the interaction of oral microorganisms, hormone and immune response
      Xingyue Wen, Xiangqing Fu, Chongjun Zhao, Lei Yang, Ruijie Huang
      Frontiers in Microbiology.2023;[Epub]     CrossRef
    • The effectiveness of prenatal care programs on reducing preterm birth in socioeconomically disadvantaged women: A systematic review and meta-analysis
      Solmaz Mohammadi, Kobra Shojaei, Elham Maraghi, Zahra Motaghi
      Iranian Journal of Nursing and Midwifery Research.2023; 28(1): 20.     CrossRef
    • Socioeconomic Risk Factors for Preterm Birth in Manipur, Northeast India: A Community-Based Study
      Thangjam Chitralekha Devi, Huidrom Suraj Singh
      Journal of Health and Allied Sciences NU.2023; 13(04): 568.     CrossRef
    • Vulvovaginal yeast infections during pregnancy and perinatal outcomes: systematic review and meta-analysis
      Ranjana M. S. Gigi, Diana Buitrago-Garcia, Katayoun Taghavi, Cara-Mia Dunaiski, Janneke H. H. M. van de Wijgert, Remco P. H. Peters, Nicola Low
      BMC Women's Health.2023;[Epub]     CrossRef
    • Incidence and Determinants of Low birth weight babies at rural tertiary care hospital in central Uttar Pradesh
      Kripashankar Nayak, Jyoti Mehra, Naresh Pal Singh, Ankita Sharma, Pankaj Kumar Jain, Kiran Krishnappa
      Indian Journal of Community Health.2023; 35(1): 83.     CrossRef
    • Oral health status of pregnant women in the Republic of Kiribati
      Yoko Kobayashi, Miwa Matsuyama
      The Journal of Medical Investigation.2023; 70(1.2): 110.     CrossRef
    • Prevalence and correlates of low birth weight in India: findings from national family health survey 5
      Damini Singh, Sayantani Manna, Manish Barik, Tanveer Rehman, Srikanta Kanungo, Sanghamitra Pati
      BMC Pregnancy and Childbirth.2023;[Epub]     CrossRef
    • Association of Pregnancy and HIV Status With Molecular-Bacterial Vaginosis in Indian Women
      Susan Tuddenham, Mehr Shafiq, Jyoti S. Mathad, Mallika Alexander, Shilpa Naik, Vandana Kulkarni, Prasad Deshpande, Mike S. Humphrys, Johanna B. Holm, Nawshaba Khan, Su Yadana, Aneesha Cheedalla, Ramesh Bhosale, Khalil G. Ghanem, Tian Wang, Shuang Wang, Bi
      JAIDS Journal of Acquired Immune Deficiency Syndromes.2023; 93(5): 422.     CrossRef
    • Correlates of low birth weight and preterm birth in India
      Arup Jana, Benedict Weobong
      PLOS ONE.2023; 18(8): e0287919.     CrossRef
    • Systematic review and meta-analysis of maternal and fetal outcomes among pregnant women with bacterial vaginosis
      Josiane Kenfack-Zanguim, Sebastien Kenmoe, Arnol Bowo-Ngandji, Raoul Kenfack-Momo, Jean Thierry Ebogo-Belobo, Cyprien Kengne-Ndé, Donatien Serge Mbaga, Elisabeth Zeuko'o Menkem, Robertine Lontuo Fogang, Serges Tchatchouang, Juliette Laure Ndzie Ondigui, G
      European Journal of Obstetrics & Gynecology and Reproductive Biology.2023; 289: 9.     CrossRef
    • A Comparative Cross-sectional Study on Prevalence of Low Birth Weight and its Anticipated Risk Factors
      Assmaa A. Alsamae, Hala A. Elzilal, Eman Alzahrani, Hala M. Abo-Dief, Mujeeb A. Sultan
      Global Pediatric Health.2023;[Epub]     CrossRef
    • Recurrent preterm birth risk assessment for two delivery subtypes: A multivariable analysis
      Ilia Rattsev, Natalie Flaks-Manov, Angie C Jelin, Jiawei Bai, Casey Overby Taylor
      Journal of the American Medical Informatics Association.2022; 29(2): 306.     CrossRef
    • molBV reveals immune landscape of bacterial vaginosis and predicts human papillomavirus infection natural history
      Mykhaylo Usyk, Nicolas F. Schlecht, Sarah Pickering, LaShanda Williams, Christopher C. Sollecito, Ana Gradissimo, Carolina Porras, Mahboobeh Safaeian, Ligia Pinto, Rolando Herrero, Howard D. Strickler, Shankar Viswanathan, Anne Nucci-Sack, Angela Diaz, Be
      Nature Communications.2022;[Epub]     CrossRef
    • Trichomonas vaginalis triggers neutrophil extracellular traps reducing parasite integrity and growth
      María G. Ramírez-Ledesma, Yordan J. Romero-Contreras, Mayra C. Rodríguez, Ruth Reyes-Cortes, Patricia Cuéllar-Mata, Eva E. Avila
      Parasitology Research.2022; 121(5): 1355.     CrossRef
    • Determinants of Low Birth Weight Among Newborns Delivered in Silte Zone Public Health Facilities, Southern Ethiopia: A Case-Control Study
      Shafi Seid, Beyene Wondafrash, Nurezeman Gali, Abdulfeta Ali, Bekri Mohammed, Shemsu Kedir
      Research and Reports in Neonatology.2022; Volume 12: 19.     CrossRef
    • Preterm birth update in Australasia: A report of the international symposium of Preterm Birth International Collaborative-Australasia branch
      Chong Qiao, Ramkumar Menon, Ki Hoon Ahn, Shunji Suzuki, Pallavi Kshetrapal, Harry Michael Georgiou, Sam Mesiano, Nanbert Zhong
      Frontiers in Pediatrics.2022;[Epub]     CrossRef
    • Effect of bacterial vaginosis on preterm birth: a meta-analysis
      Trishna Mohanty, Prakash Prabhakarrao Doke, Sana Rafiq Khuroo
      Archives of Gynecology and Obstetrics.2022; 308(4): 1247.     CrossRef
    • Prediction of low birth weight by quadruple parameters in high-risk pregnancies
      Avani Pradhan, Prabhakar Mishra, Swasti Tiwari, Kamlesh Choure, Amrit Gupta
      International Journal of Applied and Basic Medical Research.2022; 12(4): 277.     CrossRef
    • Preterm birth associated with periodontal and dental indicators: a pilot case-control study in a developing country
      María De Lourdes Márquez-Corona, Aldo Tellez-Girón-Valdez, América Patricia Pontigo-Loyola, Rosalina Islas-Zarazúa, Norma Leticia Robles-Bermeo, Blanca Silvia Gonzalez-López, Carlo Eduardo Medina-Solís
      The Journal of Maternal-Fetal & Neonatal Medicine.2021; 34(5): 690.     CrossRef
    • Rising prevalence of multidrug-resistant uropathogenic bacteria from urinary tract infections in pregnant women
      Umema Asmat, Muhammad Z. Mumtaz, Arif Malik
      Journal of Taibah University Medical Sciences.2021; 16(1): 102.     CrossRef
    • Maternal periodontal status, oral inflammatory load, and systemic inflammation are associated with low infant birth weight
      Annuroopa Mahapatra, Rashmita Nayak, Anurag Satpathy, Basanta Kumar Pati, Rinkee Mohanty, Gatha Mohanty, Rajdeep Beura
      Journal of Periodontology.2021; 92(8): 1107.     CrossRef
    • Modern pregravid management in patients with previous pelvic inflammatory diseases
      T.Yu. Pestrikova, E.A. Yurasova, I.V. Yurasov
      Rossiiskii vestnik akushera-ginekologa.2021; 21(1): 5.     CrossRef
    • Adverse pregnancy outcomes among mothers with hypertensive disorders in pregnancy: A meta-analysis of cohort studies
      Fang Li, Tingting Wang, Letao Chen, Senmao Zhang, Lizhang Chen, Jiabi Qin
      Pregnancy Hypertension.2021; 24: 107.     CrossRef
    • Daytime Napping and Nighttime Sleep During Pregnancy and Preterm Birth in Iran
      Farnaz Shaliha, Maryam Mozaffari, Faeze Ramezani, Hamideh Hajnasiri, Farnoosh Moafi
      Journal of Preventive Medicine and Public Health.2021; 54(3): 182.     CrossRef
    • Folate metabolizing gene polymorphisms and genetic vulnerability to preterm birth in Korean women
      Bit Na Kwon, Noo Ri Lee, Hyung Jun Kim, Yun Dan Kang, Jong Soo Kim, Jin Wan Park, Han Jun Jin
      Genes & Genomics.2021; 43(8): 937.     CrossRef
      Nwoga HO, Ajuba MO, Igweagu CP
      GLOBAL JOURNAL FOR RESEARCH ANALYSIS.2021; : 178.     CrossRef
    • Relationship of Anemia in Pregnancy and Low Birth Weight Infants
      Ghina Syafiqoh, Reni Ghrahani, Tetty Yuniati
      Pediatric Oncall.2021;[Epub]     CrossRef
    • Screening and management options for severe thinness during pregnancy in India
      Vani Sethi, Tashi Choedon, Ranadip Chowdhury, Neena Bhatia, Konsam Dinachandra, Zivai Murira, Arti Bhanot, Dinesh Baswal, Arjan de Wagt, Madhavi Bhargava, Indrapal Ishwarji Meshram, Giridhara R. Babu, Bharati Kulkarni, Hema Divakar, Chandni Maria Jacob, S
      International Journal of Gynecology & Obstetrics.2021; 155(3): 357.     CrossRef
    • Population estimates and determinants of severe maternal thinness in India
      Tashi Choedon, Vani Sethi, Ranadip Chowdhury, Neena Bhatia, Konsam Dinachandra, Zivai Murira, Arti Bhanot, Dinesh Baswal, Arjan de Wagt, Madhavi Bhargava, Indrapal Ishwarji Meshram, Giridhara R. Babu, Bharati Kulkarni, Hema Divakar, Chandni Maria Jacob, S
      International Journal of Gynecology & Obstetrics.2021; 155(3): 380.     CrossRef
    • Evaluation of maternal risk factors for preterm delivery in Fatemieh Hospital of Hamadan, Iran, 2019: A case-control study
      Samereh Ghelichkhani, SeyedehZahra Masoumi, AzamAli Shirzadeh, Salman Khazaei, Fatemeh Shahbazi
      Journal of Family Medicine and Primary Care.2021; 10(10): 3832.     CrossRef
    • Risk factors associated with preterm birth in the Dominican Republic: a case-control study
      Agustín Díaz-Rodríguez, Leandro Feliz-Matos, Carlos Bienvenido Ruiz Matuk
      BMJ Open.2021; 11(12): e045399.     CrossRef
    • Neonatal outcomes and its association among gestational diabetes mellitus with and without depression, anxiety and stress symptoms in Malaysia: A cross-sectional study
      Kai Wei Lee, Siew Mooi Ching, Fan Kee Hoo, Vasudevan Ramachandran, Seng Choi Chong, Maiza Tusimin, Noraihan Mohd Nordin, Navin Kumar Devaraj, Ai Theng Cheong, Yook Chin Chia
      Midwifery.2020; 81: 102586.     CrossRef
    • Microbiota in vaginal health and pathogenesis of recurrent vulvovaginal infections: a critical review
      Namarta Kalia, Jatinder Singh, Manpreet Kaur
      Annals of Clinical Microbiology and Antimicrobials.2020;[Epub]     CrossRef
    • Determinants of Low Birth Weight in Ghana: Does Quality of Antenatal Care Matter?
      Emmanuel Banchani, Eric Y. Tenkorang
      Maternal and Child Health Journal.2020; 24(5): 668.     CrossRef
    • Periodontal Disease and Birth Outcomes: Are We Missing Something?
      Lawrence G. Pessolano, Carolyn D. Kramer, Alexandra Simas, Ellen O. Weinberg, Caroline A. Genco, Barbara M. Schreiber
      Current Oral Health Reports.2020; 7(1): 62.     CrossRef
    • Periodontal disease and adverse pregnancy outcomes
      Yiorgos A. Bobetsis, Filippo Graziani, Mervi Gürsoy, Phoebus N. Madianos
      Periodontology 2000.2020; 83(1): 154.     CrossRef
    • Mother’s Knowledge and Behaviour Towards Oral Health During Pregnancy
      Anandina Irmagita Soegyanto, Ratu Nabila Larasati, Yuniardini Septorini Wimardhani, Buğra Özen
      Pesquisa Brasileira em Odontopediatria e Clínica Integrada.2020;[Epub]     CrossRef
    • Pregnancy, oral health and dental education: an overview on the northeast of Italy
      Fulvia Costantinides, Erica Vettori, Martina Conte, Ingrid Tonni, Vanessa Nicolin, Giuseppe Ricci, Roberto Di Lenarda
      Journal of Perinatal Medicine.2020; 48(8): 829.     CrossRef
    • Asymptomatic vaginal Candida colonization and adverse pregnancy outcomes including preterm birth: a systematic review and meta-analysis
      Heleen J. Schuster, Bastienne A. de Jonghe, Jacqueline Limpens, Andries E. Budding, Rebecca C. Painter
      American Journal of Obstetrics & Gynecology MFM.2020; 2(3): 100163.     CrossRef
    • Population estimates, consequences, and risk factors of obesity among pregnant and postpartum women in India: Results from a national survey and policy recommendations
      Mansi Chopra, Naman Kaur, Konsam Dinachandra Singh, Chandni Maria Jacob, Hema Divakar, Giridhara R. Babu, Phuong Hong Nguyen, Arti Bhanot, Manisha Sabharwal, Sila Deb, Dinesh Baswal, Sarah Louise Killeen, Fionnuala M. McAuliffe, Mark A. Hanson, Vani Sethi
      International Journal of Gynecology & Obstetrics.2020; 151(S1): 57.     CrossRef
    • Effect of per Capita Income on the Relationship between Periodontal Disease during Pregnancy and the Risk of Preterm Birth and Low Birth Weight Newborn. Systematic Review and Meta-Analysis
      Carmen Alba Moliner-Sánchez, José Enrique Iranzo-Cortés, José Manuel Almerich-Silla, Carlos Bellot-Arcís, José Carmelo Ortolá-Siscar, José María Montiel-Company, Teresa Almerich-Torres
      International Journal of Environmental Research and Public Health.2020; 17(21): 8015.     CrossRef
    • Early Identification of Preterm Neonates at Birth With a Tablet App for the Simplified Gestational Age Score (T-SGAS) When Ultrasound Gestational Age Dating Is Unavailable: Protocol for a Validation Study
      Archana B Patel, Kunal Kurhe, Amber Prakash, Savita Bhargav, Suchita Parepalli, Elizabeth V Fogleman, Janet L Moore, Dennis D Wallace, Hemant Kulkarni, Patricia L Hibberd
      JMIR Research Protocols.2019; 8(3): e11913.     CrossRef
    • Sociodemographic Determinants of Preterm Birth and Small for Gestational Age in Rural West Bengal, India
      Rajesh Kumar Rai, Christopher R Sudfeld, Anamitra Barik, Wafaie W Fawzi, Abhijit Chowdhury
      Journal of Tropical Pediatrics.2019;[Epub]     CrossRef
    • Association Between Periodontal Diseases and Adverse Gestation Outcomes: a Review of the Current Literature
      Davi da Silva Barbirato, Monique Oliveira Rodrigues, Julianna Peres Alves, Heric Pinheiro de Castro, Mariana Fampa Fogacci
      Current Oral Health Reports.2019; 6(1): 47.     CrossRef
    • A Pregnancy Cohort to Study Multidimensional Correlates of Preterm Birth in India: Study Design, Implementation, and Baseline Characteristics of the Participants
      Shinjini Bhatnagar, Partha P Majumder, Dinakar M Salunke
      American Journal of Epidemiology.2019; 188(4): 621.     CrossRef
    • Preterm birth rate and dilemma of preterm labor treatment in Asia
      Jeong-Kyu Hoh, Martha Lappas, Calixia Liu, Chong Qiao, Kshetrapal Pallavi, Jun Takeda, Young Ju Kim
      Placenta.2019; 79: 68.     CrossRef
    • Incidence and recurrence risk of low birth weight in Northern Tanzania: A registry based study
      Miriam H. Mvunta, Innocent B. Mboya, Sia E. Msuya, Beatrice John, Joseph Obure, Michael J. Mahande, Massimo Ciccozzi
      PLOS ONE.2019; 14(4): e0215768.     CrossRef
      i-manager’s Journal on Nursing.2019; 8(4): 46.     CrossRef
    • The Role of Early Pregnancy Maternal Selenium Levels on the Risk for Small-for-Gestational Age Newborns
      Małgorzata Lewandowska, Stefan Sajdak, Jan Lubiński
      Nutrients.2019; 11(10): 2298.     CrossRef
    • Periodontopathogenic microbiota, infectious mechanisms and preterm birth: analysis with structural equations (cohort—BRISA)
      Elisa Miranda Costa, Camilla Silva de Araujo Figueiredo, Rafiza Félix Marão Martins, Cecília Claudia Costa Ribeiro, Claudia Maria Coelho Alves, Maria Lúcia Talarico Sesso, Ruchele Dias Nogueira, Maria da Conceição Saraiva, Marco Antônio Barbieri, Heloisa
      Archives of Gynecology and Obstetrics.2019; 300(6): 1521.     CrossRef
    • Co‐causation of reduced newborn size by maternal undernutrition, infections, and inflammation
      Per Ashorn, Lotta Hallamaa, Lindsay H. Allen, Ulla Ashorn, Upeksha Chandrasiri, Megan Deitchler, Ronan Doyle, Ulla Harjunmaa, Josh M. Jorgensen, Steve Kamiza, Nigel Klein, Kenneth Maleta, Minyanga Nkhoma, Brietta M. Oaks, Basho Poelman, Stephen J. Rogerso
      Maternal & Child Nutrition.2018;[Epub]     CrossRef
    • Associations between maternal weekly air pollutant exposures and low birth weight: a distributed lag non-linear model
      Han Wu, Baofa Jiang, Ping Zhu, Xingyi Geng, Zhong Liu, Liangliang Cui, Liping Yang
      Environmental Research Letters.2018; 13(2): 024023.     CrossRef
    • Influence of dental diseases of pregnant women on newborns’ health state
      V A Prokhodnaya
      Kazan medical journal.2018; 99(4): 586.     CrossRef
    • Maternal Risk Factors Associated with Low Birth Weight in Indonesia
      Issara Siramaneerat, Farid Agushybana, Yaowaluck Meebunmak
      The Open Public Health Journal.2018; 11(1): 376.     CrossRef
    • Role of Maternal Periodontitis in Preterm Birth
      Hongyu Ren, Minquan Du
      Frontiers in Immunology.2017;[Epub]     CrossRef
    • DOHaD at the intersection of maternal immune activation and maternal metabolic stress: a scoping review
      J. A. Goldstein, S. A. Norris, D. M. Aronoff
      Journal of Developmental Origins of Health and Disease.2017; 8(3): 273.     CrossRef
    • Genetic polymorphism of MTHFR C677T with preterm birth and low birth weight susceptibility: a meta-analysis
      Han Wu, Ping Zhu, Xingyi Geng, Zhong Liu, Liangliang Cui, Zhongchun Gao, Baofa Jiang, Liping Yang
      Archives of Gynecology and Obstetrics.2017; 295(5): 1105.     CrossRef
    • Genetic variations of MTHFR gene and their association with preterm birth in Korean women
      In Wook Hwang, Yun Dan Kang, Bit Na Kwon, Jun Ho Hong, Seung Hun Han, Jong Soo Kim, Jin Wan Park, Han Jun Jin
      Medicina.2017; 53(6): 380.     CrossRef

    JPMPH : Journal of Preventive Medicine and Public Health