Trends in birth weight and the prevalence of low birth weight and small-for-gestational-age in Surinamese South Asian babies since 1974: cross-sectional study of three birth cohorts

Background: South Asian babies born in developed countries are generally lighter than babies from other ethnic groups born in the same country. While the mean birth weight of Caucasian babies in the Netherlands has increased the past decades, it is unknown if the mean birth weight of South Asian babies born in the Netherlands has increased or if the prevalence of low birth weight (LBW) or small-for-gestational-age (SGA) has decreased. The aims of this study are: 1. to investigate secular changes in mean birth weight and the prevalence of LBW and SGA in Surinamese South Asian babies, and 2. to assess differences between Surinamese South Asian and Dutch Caucasian neonates born 2006-2009. Methods: A population based study for which neonatal characteristics of 2014 Surinamese South Asian babies, born between 1974 and 2009 in the Netherlands, and 3104 Dutch Caucasian babies born 2006-2009 were obtained from well-baby clinic records. LBW was defined as a birth weight <2500 g. SGA was based on a universal population standard (the Netherlands) and three ethnic specific standards (the Netherlands, UK, Canada). Results: In Surinamese South Asian babies from 1974 to 2009 no secular trend in mean birth weight and prevalence of LBW was found, whereas SGA prevalence decreased significantly. Surinamese South Asian babies born in 2006-2009 (2993 g; 95% CI 2959-3029 g) were 450 g lighter than Dutch Caucasian babies (3448 g; 95% CI 3429-3468 g), while LBW and SGA prevalences, based on universal standards, were three times higher. Application of ethnic specific standards from the Netherlands and the UK yielded SGA rates in Surinamese South Asian babies that were similar to Dutch. There were considerable differences between the standards used. Conclusion: Since 1974, although the mean birth weight of Surinamese South Asian babies remained unchanged, they gained a healthier weight for their gestational age.