ESPE Yearbook of Paediatric Endocrinology

Front Endocrinol (Lausanne). 2022 Mar 24;13:832678. doi: 10.3389/fendo.2022.832678. PMID: 35399939.

Brief Summary: This retrospective case note study assessed the impact of different classes of obesity on maternal and neonatal outcomes. Higher classes of maternal obesity were associated with increased rates of caesarean section, GDM and gestational hypertension and pre-eclampsia.

Obesity in pregnancy is a risk factor for adverse effects for the mother, neonate and later in childhood. In pregnancy, maternal obesity increases the risk of gestational diabetes mellitus (GDM), gestational hypertension, pre-eclampsia, instrumental delivery, Caesarean section delivery and stillbirth. Women with obesity are more likely to deliver a neonate with congenital abnormalities, large-for-gestational age (LGA) and respiratory distress syndrome. There are only few studies assessing the perinatal outcome based on the degree of maternal obesity. So, this study examined perinatal outcomes in a cohort of women categorized by degree of obesity (class 1 BMI 30.0 to 34.9 kg/m2, class II BMI 35.0 to 39.9 kg/m2 and class III and above BMI ≥40 kg/m2)).

Women with obesity class III had increased rates of caesarean section, GDM and gestational hypertension and pre-eclampsia. Stillbirth incidence was greater in women with higher obesity class. The most striking neonatal risk associated with higher class of obesity was LGA, even after adjustment for confounding variables including diabetes in any form. Women with obesity class III had a 49% increased risk of LGA. There was a significant association between obesity class and pre-eclampsia, such that women with obesity class III had at least a two-fold increased risk of pre-eclampsia compared to women with class I obesity.

The incidence of pre-eclampsia in women with obesity was 3.4% increasing to 6.2% in the women with obesity class III. However, Maternal Obesity and Long-term Infant Consequences was not greater in women with higher obesity class; instead maternal diabetes was the major determinant of Maternal Obesity and Long-term Infant Consequences . Women with class III obesity were more likely to deliver a neonate with a birth defect, however this effect was no longer significant after adjusting for other known risk factors, including diabetes and advanced maternal age.

These observations indicate that work in pre-conception weight management should be considered to reduce the number of women entering pregnancy with higher class of obesity.