Abdominal fat thickness predicts the risk of pregnancy-associated hypertension: A prospective cohort study

Pregnancy-associated hypertension (PAH) is a prevalent complication during pregnancy. Maternal obesity is a known risk factor for PAH. As nutrition is a key modifiable driver of obesity and metabolic health, this study aimed to evaluate whether early-pregnancy abdominal fat thickness and nutrient intake are associated with the development of PAH.

A prospective cohort study was conducted including pregnant women during 9 to 13+6 weeks of gestation. The abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were measured by ultrasound. Daily intake of key nutrients was assessed using a validated food frequency questionnaire. The primary outcome was development of PAH, encompassing gestational hypertension and pre-eclampsia.

A total of 1912 pregnant women were recruited in this study. The overall incidence of PAH was 7.1% (136/1912). High VAT was associated with a higher PAH incidence than normal VAT (11.2% vs. 4.5%). Independent of BMI, high SAT (≥17.05 mm; adjusted odds ratios (aOR): 2.74, 95% confidence interval (CI): 1.89-3.96) and high VAT (≥28.85 mm; aOR: 2.42, 95% CI: 1.67-3.50) significantly increased risk of PAH. Comparatively, obesity (BMI ≥30 kg/m²) was associated with an aOR of 7.04 (95% CI: 3.94-12.6) for PAH, while the aOR for overweight was 3.16 (95% CI: 2.11-4.71). A predictive model incorporating these adiposity indicators demonstrated an area under the ROC curve of 0.745 (95%CI: 0.703-0.788). In contrast, no significant associations were observed between daily nutrient intake and PAH risk.

In this prospective cohort study, both early-pregnancy SAT and VAT are significant predictors of PAH independent of BMI. The developed predictive model facilitates the early identification of high-risk women, enabling timely interventions to reduce adverse perinatal outcomes.