Supplementary Material for: Bariatric Surgery Impacts Levels of Serum Lipids during Pregnancy

Introduction: Bariatric surgery confers a high risk for nutritional deficiencies that could affect physiologic adaptation of lipids during pregnancy. We aimed to evaluate differences in serum lipids in pregnant women after bariatric surgery compared to obese and lean mothers. Methods: 25 women with a history of Roux-en-Y gastric bypass (RYGB), 19 obese and 19 normal-weight controls were included at the 24th–28th gestational week for determination of fasting lipids with follow-up in a subgroup after delivery. Data on neonatal biometry were additionally assessed. Results: Women after RYGB showed lower total-cholesterol (TC), low-density lipoprotein C (LDL-C), non-high-density lipoprotein C (non-HDL-C) and triglycerides (TG) compared to obese mothers. Despite their higher BMI, women after RYGB showed lower TC, LDL-C and non-HDL-C than normal-weight mothers. Ultrasensitive C-reactive protein was lower in RYGB mothers than in obese ones, reaching values of lean controls. Differences remained unchanged in BMI-matched comparison. Birth weight percentiles of RYGB offspring were associated with maternal TC (r = 0.59, p = 0.021), LDL-C (r = 0.71, p = 0.003), non-HDL (r = 0.59, p = 0.021) but not HDL-C or TG. After delivery, lipids decreased in all women; however, TC and LDL-C showed more attenuated decline in mothers after RYGB than control women. Conclusion: Pregnancies after RYGB show alterations of physiologic patterns in lipid profile. Further studies are required to evaluate whether imbalances in maternal lipids constitute a risk for abnormal fetal growth in this special cohort.