ABSTRACT
Preterm birth (PTB) is the leading cause of neonatal deaths and India is the biggest contributor to the global burden of PTBs. This study aimed to determine the risk of recurrence of PTBs and factors associated with recurrence among mothers delivered at a tertiary care perinatal centre in India. This retrospective study comprised women who had delivered singleton preterm babies (24-37 weeks of gestation and weighing ≥500 g) in 2009 and 2010, and had subsequent deliveries beyond 24 weeks of gestation by the end of March 2016. Preterm births were stratified as spontaneous and those with an indication for delivery. Information on demographic data and maternal and neonatal outcomes was accessed from the case records or enquired over telephone. Among 291 eligible women, the recurrence rate of PTB was 31.6%; 29.1% for prior spontaneous and 34.0% for indicated preterm deliveries. This recurrence risk is similar to that in the western populations. In 75.0% of the cases, the type of recurrent PTB corresponded to the index PTB. Preeclampsia (PE) was significantly associated with recurrence (OR 7.10; 95% CI: 3.33, 15.11; p < .001); thus, prevention of PE is a key component in the prevention of PTB.Impact StatementWhat is already known on this subject? Preventing preterm birth (PTB) remains a challenge because the causes of PTBs are numerous, complex and poorly understood. Spontaneous PTB before 34 weeks of gestation is a strong predictor of subsequent spontaneous PTB. Spontaneous PTB is not only associated with increased recurrence of spontaneous but also medically indicated PTB and vice versa. Risk factors may vary by the clinical subtype of the most recent PTB.What the results of this study add? Despite the highest reported number of PTBs, there are no data on recurrence from India. This study reveals that the recurrence rate of PTBs in an Indian population appears to mirror the rates in the developed nations and preeclampsia (PE) is strongly associated with recurrence.What the implications are of these findings for clinical practice and/or future research? The results of this study are useful for counselling women who had previous PTBs regarding their future obstetric outcomes. Focussed research on prediction and prevention of PE is an essential element in the algorithm for prevention of PTBs.