ABSTRACT
Background and Objectives:
The prevalence and risk factors of stillbirths vary across geographical and socioeconomic contexts, extending beyond maternal and fetal factors. Many of these risks are preventable with quality pregnancy care. Prevention relies on recognizing and appropriately addressing these factors.
Methods:
This was a descriptive cross-sectional study done at a referral hospital, Patna, Bihar in 2023–2024. All pregnancies complicated with stillbirths were included. Data regarding demographic details, chief complaints, comorbidities, clinical, and laboratory parameters were collected and analyzed in MS Excel.
Results:
The study involved 5666 deliveries, noting 76 stillbirths (SBR of 13.4/1000 births). Most affected women were aged 25–35 (63%) and from rural areas (70%), with low education (42% up to middle school). Majority belonged to a low socioeconomic class. Few had consanguineous marriages (4%). Primigravida accounted for 52.6%, with inadequate antenatal visits (68%). Stillbirths mostly occurred between 30th and 37th weeks and were associated with pregnancy complications like hypertension (19.7%) and oligohydramnios (48.68%). Female fetuses numbered 41, with 50% showing intrauterine growth retardation. Complaints mainly included decreased fetal movement (66%) and abdominal pain (43%), sometimes occurring together (24%).
Conclusion:
The study reveals a higher stillbirth rate despite improved education among lower-income women. Pregnancy-related hypertension is a significant risk factor associated with IUGR. Poor antenatal care, healthcare gaps, and limited awareness in rural areas contribute to hypertension-related complications and stillbirths. High uterine rupture rates likely due to delayed diagnosis highlight the need for improved maternal–fetal health awareness, better rural healthcare, and strong societal and political commitment to pregnancy management goals.
Keywords: Antenatal, intrauterine fetal death, maternal, pregnancy, risk factor, stillbirth
Introduction
Stillbirth is a severe physical and psychosocial trauma to the women’s health and a financial burden to her family. Around 84% of stillbirths occur in low- and lower-middle-income countries. The stillbirth is defined by World Health Organization (WHO) as “the death of fetus after 28 weeks of gestation and before or during birth.”[1,2] Approximately two million stillbirths occur in a year with a stillbirth rate (SBR) of 13.6/1000 births. The prevalence of stillbirth varies mostly depending on the country’s economy, ranging from less than five per 1000 births in high-income countries to up to 27/1000 births in low- and lower-middle-income countries.[3,4] In 2014, WHO endorsed the Every Newborn Action Plan (ENAP) which incorporated stillbirth targets of 12 stillbirths per 1000 births or lesser and ending all preventable stillbirths by 2030.[5]
Many risk factors associated with stillbirths are largely preventable with quality care during pregnancy. Maternal risk factors, including gestational hypertension, preeclampsia and eclampsia, severe anemia, malnutrition, infections, and labor-related complications, can be addressed adequately with proper follow-up and good medical care. Whatever risk factors are involved, all ultimately lead to adverse fetal and maternal outcomes.[3,4,6] Awareness of these risk factors and early detection and management will have a large impact on feto-maternal health.
Another important aspect is sociodemographic factors, including race, low- or lower-middle class, poor education, and poor health infrastructure, leading to inadequate access to health care and ultimately culminating in inadequate antenatal care, unsupervised deliveries, consanguinity advancing maternal age, etc.[3,4,7,8,9,10] Bihar is among the poor states of India having inadequate health infrastructure and poverty being an important hindrance in adequate management of pregnancy and its complications. As there is a paucity of data regarding the prevalence of risk factors associated with stillbirths in Bihar, we propose this study to estimate the prevalence of the maternal risk factors of antenatal stillbirth.
Materials and Methods
This cross-sectional single-center study was conducted at a referral gynecology and obstetrics hospital, Patna, Bihar, in 2023–2024. All singleton pregnancies complicated with stillbirths were included. Prior ethics committee approval and proper written consent from patients were taken. The stillbirth is defined by World Health Organization (WHO) as “the death of fetus after 28 weeks of gestation and before or during birth.”. Pregnancy <28 weeks, multiple pregnancies, and intrapartum stillbirths were excluded. All cases clinically diagnosed with antenatal stillbirth were confirmed by real-time ultrasonography also before declaring it stillbirth. The pregnant women were interviewed and relevant details like demographic characteristics and high-risk factors, including pregnancy-related complications and other comorbidities, were noted in data collection sheet. We collected data, including demographic details, chief complaints, comorbidities, previous pregnancies, antenatal checkups, laboratory, and clinical data from hospital records of the patients.
Statistical analysis
Microsoft Office Excel software (MSO H/S 2019) was used to record data and data analysis. Continuous variables were presented as mean and standard deviation (or median and interquartile range), while categorical variables were presented as frequency and percentage.
Results
Out of a total of 5666 deliveries conducted during the study period, 119 stillbirths were recorded. A total of 84 stillbirths occurred after the 28th week of gestation, in which 76 were antepartum stillbirths. Forty-eight women (63%) had age between 25 and 35 years. Seventy percent of women belonged to rural areas. Forty-two percent of women were educated up to middle school. Approximately three-fourths of women (77.63%) belonged to low socioeconomic class [Table 1].
Table 1.
Distribution of the studied women according to the maternal socio-demographic risk factors (n=76)
| Maternal risk factors | Number (n=76) | % percentage |
|---|---|---|
| Socio-demographic risk factors | ||
| Age (years) | ||
| <25 | 26 | 34.21 |
| 25–35 | 48 | 63.16 |
| 35+ | 02 | 02.63 |
| Mean±SD | 26.76±4.46 | |
| Residence | ||
| Urban | 23 | 30.26 |
| Rural | 53 | 69.74 |
| Education | ||
| Illiterate | 1 | 1.32 |
| Primary school | 21 | 27.63 |
| Middle school | 11 | 14.47 |
| High school | 16 | 21.05 |
| Intermediate | 22 | 28.95 |
| Graduate | 5 | 6.58 |
| Income (social level) | ||
| Lower class (<300000/annum) | 59 | 77.63 |
| Middle class (300000–1000000) | 17 | 22.37 |
| Upper class | 00 | 0.00 |
Forty women (52.6%) were primigravida and 33 (43.4%) were multigravida. A history of abortion was present in 15 women (19.7%). There was a history of stillbirth present in only six women (7.89%).
Sixty-eight percent of women had inadequate antenatal visits, i.e., less than four visits. Most of the women with inadequate ANVs (63.46%) belonged to the 25–35-year age group. Low ANV was more common in women belonging to rural areas (65%) [Table 2].
Table 2.
Relation between the decreased maternal antenatal visits (ANVs) attendance and maternal socio-demographic risk factors
| Maternal risk factors | Decreased ANV number (n=52) | % percentage |
|---|---|---|
| Socio-demographic risk factors | ||
| Age (years) | ||
| • <25 | 17 | 32.69 |
| • 25–35 | 33 | 63.46 |
| • 35+ | 02 | 3.85 |
| P | 1.34 (not significant) | |
| Residence | ||
| • Urban | 18 | 34.62 |
| • Rural | 34 | 65.38 |
| Education | ||
| • Illiterate | 00 | 0.00 |
| • Primary school | 14 | 26.92 |
| • Middle school | 05 | 9.62 |
| • High school | 12 | 23.07 |
| • Intermediate | 16 | 30.77 |
| • Graduate | 5 | 9.62 |
| Income (social level) | ||
| • Lower/upper lower (IV and V) class (<300000/annum) | 41 | 78.85 |
| • Middle [lower and upper (II and III)] class (300000–1000000) | 11 | 21.15 |
| • Upper class (I) | 00 | 0.00 |
| Gravida | ||
| • Primigravida | 29 | 55.77 |
| • G2–G4 | 22 | 42.31 |
| • G5 and G5+ | 01 | 1.92 |
| P | 0.53 |
Almost two-thirds of stillbirths occurred between 30th and 37th week of gestation. Out of 76, 59 women with stillbirth had complications associated with pregnancy. Hypertensive disorder was prevalent in 15 women (19.7%) with preeclampsia in 9 (11.84%). Oligohydramnios was the commonest complication affecting 48.68% [Table 3].
Table 3.
Distribution of the studied women with stillbirths according to gestational age and complications during present pregnancy (n=76)
| Maternal risk factors | Number (n=76) | % percentage |
|---|---|---|
| GA at the onset of present stillbirth in weeks | ||
| • 28+ | 09 | 11.84 |
| • 30+ | 51 | 67.11 |
| • 37+ | 16 | 21.05 |
| Range | 23–43 | |
| Mean±SD | 34.75±3.46 | |
| Complications during present pregnancy | (n=76) | (%) |
| • No complication | 17 | 22.36 |
| • Complications* | 59 | |
| a. Abruption | 4 | 5.26 |
| b. Cholestasis | 8 | 10.52 |
| c. Gestational hypertension | 4 | 5.26 |
| d Preeclampsia | 9 | 11.84 |
| e. Eclampsia | 2 | 2.63 |
| f. Gestational diabetes mellitus | 3 | 3.94 |
| g. Oligohydramnios | 37 | 48.68 |
| h. Polyhydramnios | 1 | 1.31 |
| i. Postdated | 1 | 1.31 |
| j. PPROM | 4 | 5.26 |
| k. PROM | 9 | 11.84 |
| l. Rupture uterus | 5 | 6.57 |
| m. Sepsis | 3 | 3.94 |
PPROM, preterm premature rupture of membrane; PROM, premature rupture of membrane. *Total numbers are more as few patients had more than one complication
Decreased fetal movement was the most common presenting complaint in 66% of cases followed by pain abdomen in 43%. Both complaints were simultaneously present in 24% of cases.
The mode of delivery was vaginal in 55 cases, followed by lower segment caesarian section (LSCS) in 15 cases. Six patients needed laparotomy and repair of the uterus.
Forty-one fetuses had female gender. Intrauterine growth retardation was detected in 38 fetuses (50%). The mean fetal weight was 2164.46 ± 780.32 grams. The majority of the fetuses were having birth weights between 2000 gram and 3000 gram (43%), followed by 26 fetuses weighing 1000–2000 grams.
Discussion
Stillbirth is a very stressful event for the woman and her family. An estimated 2.6 million stillbirths occurred in 2015. Around 1.9 million babies, or one every 16 seconds, were stillborn in 2021.[1] In 2015, India reported total stillbirths of 592100 with a stillbirth rate of 23/1000 births.[3,4,11,12] Variable SBR has been reported in different studies from India and abroad, strikingly depending on geographical areas and socioeconomic status. Most of the third-world countries have achieved the ENEP goal and have better SBR compared to lower or lower-middle-income countries.[13] India had made substantial progress in reducing the stillbirth rate over the past two decades. India is among the member countries that adopted the ENEP earliest in 2014 and developed the Indian New-Born Action Plan (INAP). The rate had declined to 12 stillbirths per 1,000 births in 2021, from 29.6 in 2000—a 53% reduction. Globally, a 35% reduction in the stillbirth rate was recorded in this period [Table 4].
Table 4.
Recent trends of stillbirth rate (SBR) of India over the last 10 years[13]
| Uncertainty bounds | Stillbirth estimate of India | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
| |||||||||||
| 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | |
| Lower | 17 | 17 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 11 | 10 |
| Median | 20 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 13 | 12 |
| Upper | 23 | 22 | 22 | 21 | 20 | 18 | 17 | 16 | 15 | 15 | 15 |
Source: Unicef global databases [data.unicef.org]. Last update: January 10, 2023. Accessed January 5, 2024
In our study, SBR was 14.8/1000 births which is significantly higher than the national SBR (9/1000 births) and also higher than the SBR of Bihar (11/1000 births).[12] SBR at our hospital was 12.8 and 15.6 per thousand births in 2023 and 2022, respectively. The higher SBR rate may be because of our center being a referral hospital and the majority of patients belonging to rural areas. The SBR reported in various Indian studies is shown in Table 5.
Table 5.
Stillbirth rate (SBR) estimate reported in Indian studies
| Study | SBR/1000 births (IQR) | Year | Reference |
|---|---|---|---|
| Sharma B et al. | 67.9 | 2007–2016 | 7 |
| Altijani et al. | 10 (95% CI 9.8 to 10.3) | 2010–2013 | 8 |
| Newtonraj | 16 | 2014 | 14 |
| Dandona R | 21.2 | 2017 | 9 |
| Purbey | 13.4 [4.2–24.2] | 2017–18 | 10 |
| Purbey | 13.1 [4.2–22.2] | 2018–2019 | 10 |
| Purbey | 12.4 [3.7–22.5] | 2019–20 | 10 |
| NFHS 5 | 9.7 (9.2–10.1) | 2019–2021 | 15 |
| Present study | 15.5 | 2023–24 | - |
NFHS, National Family Health Survey; SBR, stillbirth rate
Dandona et al.[9] conducted a study in Bihar, India, from 2011 to 2014, using verbal autopsy interviews to analyze stillbirths and make recommendations for the Indian Newborn Action Plan (INAP). They highlighted maternal conditions, lack of antenatal care, and inadequate healthcare provider skills as contributing factors. Purbey et al.[10] showed different SBR in different geographical areas. The authors raised concerns over low SBR data from a few states, notably Bihar, UP and northeast regions, suspecting inadequacy in data collection and reporting.
In our study, 63.46% of women belonged to the age group of 25–35 years and 17% below 25 years, while Altijani et al. reported a prevalence of 46.5% and 41% in the age group of 25–35 yrs and <25 years, respectively.[8] Das R et al.[14] reported a prevalence of 51% in the age group of 30–40 years, while McClure et al.[15] reported 60% of women belonging to the age group of 20–25 years.
We observed stillbirth more common in primigravida (52.63%) similar to the finding of 43% by McClure et al.[16] Das R et al. and Altijani et al. both showed a higher prevalence among multipara women (72.35 and 51.8%).[8,14] A history of previous abortion was seen in up to one-fifth patients.
We reported 70% women residing in rural areas. Similar findings were reported by from other parts of India. The prevalence of stillbirth was higher among women in rural than in urban (0.7 vs 0.9).[8,12]
Our study reports a better educational status despite belonging to a poor socioeconomic class. None of the women was illiterate. A similar finding of 39% and 27% having secondary and tertiary education was reported from McClure,[16] while poorer educational status was reported by Altijani with illiteracy in 51.6%, primary, secondary, and tertiary education in 38.1%, 8.2%, and 2.2%, respectively.[8] Bihar has recently strengthened its education system, especially in rural areas in recent years, and better educational status may reflect government efforts. But in contrast, improved educational status did not have a bearing on maternal and fetal wellbeing.[8]
The prevalence of preterm stillbirths (<37 weeks) was 79% in this study, while other studies reported 61.3%, 55%, and 39%.[14,16,17] Stillbirth was slightly more common in the male fetus (54% vs 46%) similar to other studies but in contrast to a study from Chandigarh.[8,10]
While WHO recommends at least eight antenatal visits during pregnancy, only 10.6% of patients in our study had >eight visits. 68.4% of women had ANV less than four during the study period. Sixty-five percent of women from rural areas had inadequate ANVs in comparison with 34% urban population having lesser ANVs. Poor ANV in our study corroborates with most of the studies from India.
In the present study, three-fourths of stillbirths were delivered vaginally which is expected as this is standard practice to deliver the stillbirth vaginally unless indicated. This is in line with other studies also reporting vaginal delivery in 96.7% and 89.95%.[14,16]
Baby birth weight was 2000 gram to 3000 gram in 43.42%. A study from Shilong[14] showed 28.12% below 2000 gram, while the PURPOSe study[16] reported 43% underweight babies. Contrary to these findings, Sharma B showed a prevalence of 56.4% fetuses being >2500 gram. This difference may reflect the socioeconomic and health infrastructure status in those geographical areas.[7]
Hypertensive disorder was the most common maternal complication, followed by cholestasis (10.52%) and gestational diabetes mellitus (3.94%). The prevalence of hypertensive disorders in pregnancy (19%) was in line with other Indian studies reporting 10.5%, 16.5%, and 19.4%, but much lower than reported by McClure (37%).[8,14,15,16,17]
We reported a low prevalence of abruptio placentae compared to studies from India reporting a prevalence of 19% and 17.17%.[14,17] Rupture of the uterus complicated five pregnancies (6.57%). Increased incidence of rupture uterus was mostly due to late referral of the patient from the periphery indicating inadequate health infrastructure in rural areas.[16,17]
We found IUGR in 50% of cases. This is much higher in contrast to that reported by McClure (29%), Newtonraj et al. (19.4%), and Das R et al. (4.16%). The incidence of IUGR was directly related to the prevalence of hypertensive disorders of pregnancy.[14,16,17] Poor socioeconomic status, poor nutrition especially in rural population, inadequate ANs, and late referral may contribute to high IUGR incidence.
Strength of this study
This study represents the initial attempt to assess maternal risk factors associated with antenatal stillbirths among women in Bihar. Our institute stands as one of the largest referral centers offering obstetric and gynecological services, potentially representing data from this region.
Limitations
Due to the cross-sectional hospital-based study design and small numbers, this research was unable to estimate SBR and establish the causality of risk factors. Single-center study may not be representative of the whole population. This study did not include intrapartum stillbirths and assess the fetal risk factors, especially placental and genetic factors.
Conclusion
The study reveals a higher stillbirth rate despite improved female education within the cohort, predominantly comprising individuals from lower socioeconomic backgrounds and rural backgrounds. More than half were primigravida. Hypertensive disorder during pregnancy emerged as a prominent risk factor, associated with intrauterine growth restriction (IUGR). Inadequate ANVs correlated with the prevalent hypertension and stillbirth, notably among rural primigravidae, indicating insufficient awareness among patients and healthcare providers and a deficient regional healthcare system. A previous history of abortion was seen in one-fifth patients. The study identified a higher incidence of uterine rupture.
Hypertensive disorders of pregnancy, rural background, low socioeconomic strata, inadequate ANVs, primigravida, and history of previous abortion emerged as major risk factors for stillbirths in Bihar.
Outcome of this study
The study highlights gaps in maternal and fetal care, paving the way for strategies to address these deficiencies. Our findings will contribute to formulating effective approaches aimed at bridging these gaps, facilitating better resource allocation to maximize benefits for this cohort. Addressing these challenges requires increased awareness regarding maternal–fetal health, strengthened rural healthcare infrastructure, and strong societal and political commitment to achieve the INAP goals. This study may provide basis for further multicentric studies to estimate the stillbirth rate, prevalence of maternal risk factors and to ascertain the causality.
Concept and design
Monika Gupta, Meena Samant, Jayoti Malhotra, Prit Pal Singh.
Acquisition, analysis, or interpretation of data
Monika Gupta, Meena Samant, Jayoti Malhotra.
Drafting of the manuscript
Monika Gupta, Meena Samant, Jayoti Malhotra, Prit Pal Singh.
Critical review of the manuscript
All authors reviewed the manuscript before submission.
Conflicts of interest
There are no conflicts of interest.
Acknowledgement
I express my gratitude to Dr. Shefali Kuntal for her help in statistical analysis. I thank my colleagues for helping in collecting the data and to all mothers for their participation in the study.
Funding Statement
Nil.
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