Predictors of Adverse Pregnancy Outcomes in Pregnant Women Living with Obesity: A Systematic Review

Abstract

Obesity is a well-recognized risk factor for pregnancy complications. Most studies to date are in large cohorts, with results presented in a way that assumes all women living with obesity are at equal risk. This study investigates which women living with obesity are at higher risk of specific pregnancy complications. A systematic search of MEDLINE and Embase identified 7894 prospective or retrospective cohort studies exploring predictors of adverse outcomes among pregnant women living with obesity. Following screening, 61 studies were deemed eligible. Studies were selected if the effects of exposure to any predictor amongst pregnant women living with obesity could be collected. Maternal characteristics assessed for association with adverse outcomes included maternal age, race/ethnicity, maternal height, mode of conception, complement activation factors, and history of various comorbidities/procedures. Gestational diabetes mellitus was the most studied outcome (n = 32), followed by preterm birth (n = 29), preeclampsia (n = 27), low birthweight infants (n = 20), small for gestational age newborns (n = 12), and stillbirth (n = 7). This review identified important characteristics that should be considered during the screening and follow-up sessions of pregnant women living with obesity, including pre-existing type 1 diabetes, maternal age <20 years or ≥35 years, non-White ethnicity, abdominal adiposity obesity, and history of bariatric surgery.

Association between Pre-Pregnancy Overweightness/Obesity and Pregnancy Outcomes in Women with Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis

“…The association between pre-pregnancy BMI value and pregnancy outcomes remains inconclusive in women with PCOS. Additionally, we believe the fact that worse pregnancy outcomes are present in pregestational overweight/obese women, regardless of whether they are diagnosed with PCOS or not [ 22 , 23 , 24 , 25 , 26 ]. Therefore, we thus performed this systematic review and meta-analysis to elucidate the association between pre-pregnancy overweightness/obesity and pregnancy outcomes in the PCOS women.…”

Atualizações sobre a influência da obesidade no surgimento do diabetes gestacional e suas complicações para mãe e para concepto

“…No Reino Unido, dados atualizados que foram divulgados em 2021 sugerem que 22% das mulheres iniciam a gravidez com um IMC na faixa obesa. (Heslehurst et al, 2022).…”

Polycystic Ovarian Syndrome (PCOS): Does the Challenge End at Conception?

“…The first study [ 80 ], was a systematic review of 7894 prospective or retrospective cohort studies exploring predictors of adverse outcomes among pregnant women living with obesity. The results showed that pre-pregnancy type 1 diabetes, non-White ethnicity, specific groups of maternal age (<20 years and ≥35 years), abdominal adiposity obesity, and history of bariatric surgery were found to increase the risks of preeclampsia, low birth weight/small-for-gestational-age, preterm birth, gestational diabetes mellitus, and stillbirth.…”

“…Although the two studies above identified demographic and phenotypic features in obese patients associated with pregnancy risks, these features on their own do not explain the mechanisms. However, the paper by Fakhraei et al [ 80 ] suggested that there was increasing evidence to implicate obesity-associated low-level inflammatory mediators as important contributors to these risks, linking maternal obesity and/or an obesogenic diet with altered adipokine secretion, insulin resistance, and increased circulating lipids, which in turn are associated with increased levels of markers of inflammation (including interleukin-, interleukin-1β, and tumor necrosis factor-α). Several of these markers of inflammation which are also elevated in PCOS have been associated with placental inflammation, altered placental nutrient transport, and altered placental structure, all of which have the potential to increase the risks of preeclampsia, fetal growth restriction, preterm birth, and stillbirth in PCOS.…”