Risk-Benefit Balance Associated With Obstetric, Neonatal, and Child Outcomes After Metabolic and Bariatric Surgery

Pregnancy Outcomes After Bariatric Surgery: Importance of Maternal Ferritin on Birth Weight

PURPOSE

The risks carried by pregnancy after bariatric surgery (BS) include small-for-gestational age (SGA) newborn and prematurity. However, the underlying mechanisms are not yet fully understood in pregnant women after BS.

MATERIAL AND METHODS

This single-center retrospective observational cohort study includes all women with a first and single pregnancy after BS who completed at least one clinical and biological nutritional assessment during pregnancy between 2010 and 2016. The quarterly biological assessment comprised blood count, ferritin, calcium, 25OH vitamin D, parathyroid hormone, fasting glucose, albumin, prealbumin, vitamin A, vitamin B12, folic acid, and zinc.

RESULTS

Among 120 pregnancies analysed, two-thirds underwent gastric bypass (Roux-en-Y and one-anastomosis) and one-third a restrictive procedure (adjustable gastric band or sleeve gastrectomy). The median [Q1-Q3] preoperative BMI was 43.8 [41.1-47.7] kg/m2 and the mean age at pregnancy was 32.6 ± 5.3 years. Weight loss and time from surgery to pregnancy were 35.1 ± 15.4 kg and 2.9 [1.3-4.5] years, respectively. Ten women (8%) gave birth prematurely, and 22 newborns (19%) were SGA. Univariate analysis shows that ferritin was significantly higher in mothers with SGA than in those without SGA (35.5 [22.3-69.5] vs. 15 [10-32] ng/ml) at third trimester of pregnancy. Women who received pre-pregnancy nutritional assessment seemed less likely to give birth to a SGA newborn (32% vs. 54%, p = 0.07).

CONCLUSION

Iron supplementation should be carefully prescribed and closely monitored during pregnancy in women who have undergone BS.

Comparison of pregnancy outcomes after bariatric surgery by sleeve gastrectomy versus gastric bypass

Objective

Bariatric surgery has an impact on subsequent pregnancies, in particular an association between gastric bypass and small for gestational age. Knowledge is lacking on whether sleeve gastrectomy is associated with more favorable pregnancy outcomes. This study aimed to compare the impact of sleeve gastrectomy and Roux-en-Y gastric bypass on the incidence of small for gestational age (SGA), and of adverse pregnancy outcomes.

Study design

We conducted a retrospective study in a single reference center, including all patients with a history of sleeve or bypass who delivered between 2004 and 2021 after their first pregnancy following bariatric surgery. We compared the incidence of SGA, intrauterine growth retardation, preterm delivery and adverse maternal outcomes between patients who had sleeve versus bypass.

Results

Of 244 patients, 145 had a sleeve and 99 had a bypass. The proportion of SGA < 10th percentile did not differ between the two groups (38/145 (26.2 %) vs 22/99 (22.22 %), respectively, p = 0.48). Preterm birth < 37 WG was lower in the sleeve group (5/145 (3.45%) vs 12/99 (12.12 %) in the bypass group (p = 0.01), as well as NICU hospitalizations (3 (2.07%) vs 12/99 (12.12%), p < 0.01). There was no difference regarding adverse maternal outcomes such as gestational diabetes and hypertensive complications. The proportion of SGA was not lower in patients with bypass when adjusting for other risk factors (BMI, smoking, geographic origin, diabetes and hypertension) (aOR 0.70; 95%CI 0.01 - 2.85).

Conclusion

sleeve was associated with an incidence of SGA which was as high as after bypass, however the incidence of preterm birth was lower.

Maternal and long-term offspring outcomes of obesity during pregnancy

PURPOSE

Obesity`s prevalence is rising in women of reproductive age worldwide and has become the most common medical condition at this age group. Besides, its occurrence is also rising during pregnancy. This condition not only increases the risk of noncommunicable diseases on the mother, such as cardiovascular disease and diabetes, but also transfers this risk to the offspring.

METHODS

This is a narrative review based on scientific and review articles on the matter.

RESULTS

Obesity is associated with an increased risk of gestational diabetes mellitus, gestational hypertension and preeclampsia, venous thromboembolism, infection, and mental health problems. Furthermore, it has an impact on the progress of labor and induction matters. Regarding offspring outcomes, it is related to higher incidence of congenital anomalies, perinatal mortality, and the occurrence of large for gestational age newborns. Still, it has implications on cardiometabolic risk and neurodevelopment in offspring.

CONCLUSION

It is, therefore, imperative to encourage the adoption of healthy lifestyles, especially in the peri-conception and interpregnancy periods. Likewise, there must be support in the multidisciplinary monitoring of these pregnant women to minimize associated complication rates.

Maternal GLP-1 receptor activation inhibits fetal growth

Glucagon-like peptide 1 (GLP-1) regulates food intake, insulin production, and metabolism. Our recent study demonstrated that pancreatic α-cells-secreted (intraislet) GLP-1 effectively promotes maternal insulin secretion and metabolic adaptation during pregnancy. However, the role of circulating GLP-1 in maternal energy metabolism remains largely unknown. Our study aims to investigate systemic GLP-1 response to pregnancy and its regulatory effect on fetal growth. Using C57BL/6 mice, we observed a gradual decline in maternal blood GLP-1 concentrations. Subsequent administration of the GLP-1 receptor agonist semaglutide (Sem) to dams in late pregnancy revealed a modest decrease in maternal food intake during initial treatment. At the same time, no significant alterations were observed in maternal body weight or fat mass. Notably, Sem-treated dams exhibited a significant decrease in fetal body weight, which persisted even following the restoration of maternal blood glucose levels. Despite no observable change in placental weight, a marked reduction in the placenta labyrinth area from Sem-treated dams was evident. Our investigation further demonstrated a substantial decrease in the expression levels of various pivotal nutrient transporters within the placenta, including glucose transporter one and sodium-neutral amino acid transporter one, after Sem treatment. In addition, Sem injection led to a notable reduction in the capillary area, number, and surface densities within the labyrinth. These findings underscore the crucial role of modulating circulating GLP-1 levels in maternal adaptation, emphasizing the inhibitory effects of excessive GLP-1 receptor activation on both placental development and fetal growth.NEW & NOTEWORTHY Our study reveals a progressive decline in maternal blood glucagon-like peptide 1 (GLP-1) concentration. GLP-1 receptor agonist injection in late pregnancy significantly reduced fetal body weight, even after restoration of maternal blood glucose concentration. GLP-1 receptor activation significantly reduced the placental labyrinth area, expression of some nutrient transporters, and capillary development. Our study indicates that reducing maternal blood GLP-1 levels is a physiological adaptation process that benefits placental development and fetal growth.