Introduction
The rates of overweight and obesity continue to increase worldwide.1 In women, pregnancy is a life stage that can alter their weight trajectory due to the risk of weight gain during or between pregnancies.2, 3 Higher parity has been associated with higher pre-pregnancy body mass index (BMI) and subsequent development of obesity.4, 5 On average, women gain approximately 1 kg/m2 of BMI unit between consecutive pregnancies, with greater interpregnancy weight gain observed in those with a higher weight before pregnancy.6
In women who are overweight or obese, or underweight, the risks of adverse perinatal outcomes are well documented.7, 8However, the extent to which interpregnancy weight change influences the risks of subsequent maternal and neonatal outcomes remain poorly understood,9 and most studies have been focused on Western populations.10 Given that Asians have increased health risks at different BMI thresholds to Caucasians,11 and that unique sociocultural factors may influence weight management behaviours before, during, and after pregnancy,10 it is essential to personalize weight management planning for Asian women.
The interpregnancy period represents a unique phase of the reproductive life-course. A recent systematic review and meta-analysis pooling 61 studies investigating outcomes of interpregnancy weight changes from 11 Western countries highlighted the gaps and clinical needs.10 Data from this meta-analysis showed that women with interpregnancy weight gain had increased risks of gestational diabetes, hypertensive disorders, large-for-gestational-age birth and caesarean delivery, while those with interpregnancy weight loss had increased risks for preterm delivery and small-for-gestational-age birth. In the present study, our aims were to (i) describe the distribution of weight changes in BMI between first and second pregnancies among Singaporean women and (ii) examine whether similar associations between interpregnancy BMI changes and pregnancy outcomes would be observed in Asian women, compared to those reported in the aforementioned meta-analysis among Caucasians.10