Independent effect of gestational weight gain and prepregnancy obesity on pregnancy outcomes among Saudi women: A sub-cohort analysis from Riyadh mother and baby cohort study (RAHMA)

Background Gestational weight gain (GWG) and prepregnancy obesity are garnering more attention as determining factors of pregnancy outcomes when it comes to the wellbeing of both the mother and her baby. This study was conducted to describe the pattern of GWG among participants of Riyadh Mother and Baby Multicenter Cohort Study (RAHMA) and to investigate the detrimental effects of excessive GWG and prepregnancy obesity on pregnancy outcomes. Methods RAHMA is a multicentre cohort study conducted in three hospitals in Riyadh, Saudi Arabia. Participants were categorized according to the Institute of Medicine into inadequate, adequate, and excessive GWG, and stratified by body mass index (BMI) into under/normal weight, overweight, and obese. To examine the independent effect of maternal prepregnancy obesity and GWG, a multivariate regression model was used and adjusted odds ratio (AOR) and 95% Confidence Interval (CI) for each outcome were calculated. Results A total of 7029 participants were included in this study; 31.8% had adequate GWG, 25.9% had excessive GWG and 42.3% had inadequate GWG, while 29.7% had normal BMI, 33.3% were overweight, 34.8% were obese, and 2.2% were underweight. Excessive GWG was independently associated with increased risk of hypertensive events, (AOR = 1.77, 95% CI 1.20–2.63). Obesity was associated with higher risk of gestational diabetes (AOR 2.11, 95% CI 1.76–2.53), hypertensive events (AOR 2.06, 95% CI 1.48–3.01), and delivery by emergency caesarean section (AOR = 1.63, 95% CI 1.35–1.97). Infants of obese women had increased odds of macrosomia (AOR 3.11, 95% CI 1.94–4.99) and lower odds of low birth weight (AOR = 0.68, 95% CI 0.53–0.88). Conclusion In comparison to excessive GWG, which increases the risk of hypertensive events during pregnancy, prepregnancy obesity is associated with more adverse outcomes including GDM, hypertensive events in pregnancy and emergency CS.

The Relationship between Telomere Length and Gestational Weight Gain: Findings from the Mamma & Bambino Cohort

Inadequate gestational weight gain (GWG) affects a growing number of pregnancies, influencing intrauterine environment and long-term health. Uncovering molecular mechanisms associated with GWG could be helpful to develop public health strategies for tackling this issue. Here, our study aimed to understand the relationship of DNA telomere length with weigh gain during pregnancy, using data and samples from the ongoing prospective “Mamma & Bambino” study (Catania, Italy). GWG was calculated according to the Institute of Medicine (IOM) guidelines. Relative telomere length was assessed by real-time quantitative polymerase chain reaction in 252 samples of maternal leucocyte DNA (mlDNA) and 150 samples of cell-free DNA (cfDNA) from amniotic fluid. We observed that relative telomere length of mlDNA seemed to weakly increase with GWG. In contrast, telomere length of cfDNA exhibited a U-shaped relationship with GWG. Women with adequate GWG showed longer telomere length than those who gained weight inadequately. Accordingly, the logistic regression model confirmed the association between telomere length of cfDNA and adequate GWG, after adjusting for potential confounders. Our findings suggest an early effect of GWG on telomere length of cfDNA, which could represent a molecular mechanism underpinning the effects of maternal behaviours on foetal well-being.