Risk Factors for Stillbirths: A Case-control Study

Introduction: The occurrence of Stillbirths (SBs) is a tragic event faced by the obstetrician and causes great psychological trauma and emotional devastation to the couple and the family. It is estimated that approximately 3.2 million stillbirths occur in the world every year. The SB rate across India is about 20 per 1,000 live births accounting for highest absolute number of stillbirth in the world. Aim: To analyse the risk factors for stillbirths in a tertiary teaching centre in northern India. Materials and Methods: Sample size was calculated to be 150. In the study institution, nearly 600 stillbirths occur annually and since the required sample size was 150, every 4th woman delivering a stillbirth was included as case and the live birth matched for gestational age consecutive to the case was taken as control. All babies of the study and control group were examined by the neonatologist. Mothers of all babies were interviewed through a stillbirth review proforma (by WHO apps SEARO) within 24 hours of delivery. Qualitative data analysis was done by chi-square test and quantitative data by using t-test. The p-value <0.05 was be considered significant. Logistic regression was applied to get odds ratio for the risk prevalence. Variables with statistically significant association on univariate analysis were included in a multivariable binary logistic regression model. Results: Stillbirth rate was 25.4 per 1000 births. A significant association of pre-existing hypertension (p=0.008) and anaemia (p=0.05) as maternal comorbid conditions were found with stillbirths. There were 66 Fresh SBs (44%) and 84 Macerated SBs (56%). When intrapartum risk factors were analysed, significant association was found with antepartum haemorrhage, cord prolapse, malpresentation, obstructed labour and rupture uterus as compared to control group. On multivariate analysis of various risk factors, maternal age >30 years, maternal BMI >25 kg/m(2), antenatal checkups <3 in number, maternal illiteracy, lack of periconceptional folic acid intake along with preexisting hypertension, fetal malpresentation, and antepartum haemorrhage were observed to have an independent, significant association with the occurrence of stillbirths. Conclusion: Among sociodemographic factors, older mothers, obesity, inadequate antenatal checkups, lack of maternal education, lack of periconceptional folic acid intake were associated with high risk of SBs. Maternal morbidity especially pre-existing hypertension which led to antepartum haemorrhage along with fetal malpresentation was observed to have an independent, significant association with the occurrence of SBs. Hence apart from improved intrapartum care, essential screening during antenatal visits with allotment of cards of varied identity with appropriate precedence can be an important step in monitoring the high-risk cases which can also prove crucial in timely referral to tertiary care units.