[Impact of bariatric surgery on obstetric prognosis]

Glucose Abnormalities and Inappropriate Weight Gain Predict Negative Pregnancy Outcomes After Gastric Bypass Surgery

PURPOSE

Pregnancy after gastric bypass (RYGB) surgery remains at high risk for gestational diabetes mellitus, prematurity, and small for gestational age infants (SGA). Our objective was to describe the interstitial glucose (IG) profiles and weight changes during such pregnancies, and the association of these factors with adverse pregnancy outcomes.

MATERIAL AND METHODS

One hundred twenty two pregnancies were analyzed in a monocentric retrospective study. IG profiles were evaluated by continuous glucose monitoring for 4 days. Maternal (hypertension, hospitalizations, and caesarean section) and neonatal outcomes (prematurity, weight for gestational age, hospitalizations, and malformations) were recorded. A logistic stepwise regression model assessed the influence of weight gain and impaired IG on pregnancy outcomes.

RESULTS

Pregnancies occurred 33 (SD 21 months) after surgery. 73% of the women had IG abnormalities (55% with an increased % of time >140 mg/dl and 69% with an increased % of time <60 mg/dl). Five (4%) children were large for gestational age (LGA), 24 (20%) were SGA and 16 (13%) were born prematurely. There were 3 malformations but no stillbirth. LGA was associated with a high % of time >140 mg/dl and an excessive maternal weight gain. Prematurity was associated with a high % of time <60 mg/dl and an insufficient maternal weight gain. In the multivariate analysis, inappropriate weight gain explained LGA and prematurity independently. SGA was associated with a shorter % of time <60 mg/dl.

CONCLUSION

The relationship between IG abnormalities and/or maternal weight gain and neonatal outcomes in pregnancies after RYGB, suggests a careful monitoring of these parameters.

Pregnancy after bariatric surgery and adverse perinatal outcomes: A systematic review and meta-analysis

BACKGROUND

Women who undergo bariatric surgery prior to pregnancy are less likely to experience comorbidities associated with obesity such as gestational diabetes and hypertension. However, bariatric surgery, particularly malabsorptive procedures, can make patients susceptible to deficiencies in nutrients that are essential for healthy fetal development. The objective of this systematic review and meta-analysis is to investigate the association between pregnancy after bariatric surgery and adverse perinatal outcomes.

METHODS AND FINDINGS

Searches were conducted in Medline, Embase, PsycINFO, CINAHL, Scopus, and Google Scholar from inception to June 2019, supplemented by hand-searching reference lists, citations, and journals. Observational studies comparing perinatal outcomes post-bariatric surgery to pregnancies without prior bariatric surgery were included. Outcomes of interest were perinatal mortality, congenital anomalies, preterm birth, postterm birth, small and large for gestational age (SGA/LGA), and neonatal intensive care unit (NICU) admission. Pooled effect sizes were calculated using random-effects meta-analysis. Where data were available, results were subgrouped by type of bariatric surgery. We included 33 studies with 14,880 pregnancies post-bariatric surgery and 3,979,978 controls. Odds ratios (ORs) were increased after bariatric surgery (all types combined) for perinatal mortality (1.38, 95% confidence interval [CI] 1.03-1.85, p = 0.031), congenital anomalies (1.29, 95% CI 1.04-1.59, p = 0.019), preterm birth (1.57, 95% CI 1.38-1.79, p < 0.001), and NICU admission (1.41, 95% CI 1.25-1.59, p < 0.001). Postterm birth decreased after bariatric surgery (OR 0.46, 95% CI 0.35-0.60, p < 0.001). ORs for SGA increased (2.72, 95% CI 2.32-3.20, p < 0.001) and LGA decreased (0.24, 95% CI 0.14-0.41, p < 0.001) after gastric bypass but not after gastric banding. Babies born after bariatric surgery (all types combined) weighed over 200 g less than those born to mothers without prior bariatric surgery (weighted mean difference -242.42 g, 95% CI -307.43 to -177.40 g, p < 0.001). There was low heterogeneity for all outcomes (I2 < 40%) except LGA. Limitations of our study are that as a meta-analysis of existing studies, the results are limited by the quality of the included studies and available data, unmeasured confounders, and the small number of studies for some outcomes.

CONCLUSIONS

In our systematic review of observational studies, we found that bariatric surgery, especially gastric bypass, prior to pregnancy was associated with increased risk of some adverse perinatal outcomes. This suggests that women who have undergone bariatric surgery may benefit from specific preconception and pregnancy nutritional support and increased monitoring of fetal growth and development. Future studies should explore whether restrictive surgery results in better perinatal outcomes, compared to malabsorptive surgery, without compromising maternal outcomes. If so, these may be the preferred surgery for women of reproductive age.

TRIAL REGISTRATION

PROSPERO CRD42017051537.

Maternal Nutritional Deficiencies and Small-for-Gestational-Age Neonates at Birth of Women Who Have Undergone Bariatric Surgery

The aim is to compare the prevalence of maternal deficiencies in micronutrients, the obstetrical and neonatal complications after bariatric surgery according to surgical techniques, the time between surgery and conception, and BMI at the onset of pregnancy. A retrospective cohort study concerned 57 singleton pregnancies between 2011 and 2016 of 48 adult women who have undergone bariatric surgery. Small-for-gestational-age neonates were identified in 36.0% of pregnancies. With supplements intake (periconceptional period: 56.8%, trimester 1 (T1): 77.8%, T2: 96.3%, and T3: 100.0%), nutritional deficiencies involved vitamins A (T1: 36.4%, T2: 21.1%, and T3: 40.0%), D (T1: 33.3%, T2: 26.3%, and T3: 8.3%), C (T1: 66.7%, T2: 41.2%, and T3: 83.3%), B1 (T1: 45.5%, T2: 15.4%, and T3: 20.0%), and B9 (T1: 14.3%, T2: 0%, and T3: 9.1%) and selenium (T1: 77.8%, T2: 22.2%, and T3: 50.0%). There was no significant difference in the prevalence of nutritional deficiencies and complications according to surgery procedures and in the prevalence of pregnancy issues according to BMI at the beginning of the pregnancy and time between surgery and pregnancy. Prevalence of micronutritional deficiencies and small-for-gestational-age neonates is high in pregnant women following bariatric surgery. Specific nutritional programmes should be recommended for these women.

Impact of bariatric surgery on fetal growth restriction: experience of a perinatal and bariatric surgery center

BACKGROUND

Bariatric surgery is known to improve some pregnancy outcomes, but there is concern that it may increase the risk of small for gestational age.

OBJECTIVE

To assess the impact of bariatric surgery on pregnancy outcomes and specifically of the type of bariatric surgery on the risk of fetal growth restriction.

STUDY DESIGN

A single-center retrospective case-control study. The study group comprised all deliveries in women who had undergone bariatric surgery. To investigate the effects of weight loss on pregnancy outcomes, we compared the study group with a control group matched for presurgery body mass index. Secondly, to assess the specific impact of the type of surgery on the incidence of fetal growth restriction in utero, we distinguished subgroups with restrictive and malabsorptive bariatric surgery, and compared outcomes for each of these subgroups with a second control group, matched for prepregnancy body mass index.

RESULTS

Among 139 patients operated, 58 had a malabsorptive procedure (gastric bypass) and 81 a purely restrictive procedure (72 a gastric banding and 9 a sleeve gastrectomy). Compared with controls matched for presurgery body mass index, the study group had a decreased rate of gestational diabetes (12% vs 23%, P = .02) and large for gestational age >90th percentile (11% vs 22%, P = .01) but an increased rate of small for gestational age <10th percentile. The incidence of small for gestational age was higher after gastric bypass (29%) than it was after restrictive surgery (9%) or in controls matched for prepregnancy body mass index (6%) (P < .01 between bypass and controls). In multivariable analysis, after adjustment for other risk factors, gastric bypass remained strongly associated with small for gestational age (adjusted odds ratio, 7.16; 95% confidence interval, 2.74-18.72).

CONCLUSION

Malabsorptive bariatric surgery was associated with an increased risk of fetal growth restriction.

[Digestive surgical complications during pregnancy following bariatric surgery: Experience of a center for perinatology and obesity]

OBJECTIVE

To describe severe complications during pregnancy requiring surgery in patients with a history of obesity surgery.

MATERIEL AND METHODS

A retrospective study in a hospital with tertiary care perinatology and an obesity reference center, on all pregnancies following bariatric surgery over a 10-year period, analyzing all cases of surgical complications.

RESULTS

There were 8 major complications related to the procedure in 141 pregnancies with bariatric surgery. The 2 complications in women with gastric banding were band slippage resulting in severe dysphagia, one of which leading to intractable vomiting and serious hydrolectric disorders. Among the 6 complications after bypass surgery, 4 were occlusions: 3 on internal hernias of which 2 with volvulus and 1 associated with intestinal invagination, as well as one with intestinal invagination only. One patient had a laparotomy for a suspected invagination which was not confirmed. The other surgical complications after gastric bypass were a hernia and an exploratory laparotomy for suspected intussusception which was overturned. There was no case of maternal or perinatal death.

CONCLUSION

Pregnancies in patients with a history of bariatric surgery are at high risk, in particular for complications related to the surgery and thus require careful interdisciplinary surveillance, and determination of predictive factors.

[Pregnancy and bariatric surgery: Critical points]

More than 200,000 people underwent obesity surgery in France. Most of them are women. Pregnancy after bariatric surgery is becoming a common situation. This surgery results in major nutritional and gastro-intestinal tract modifications that may influence or be influenced by pregnancy, and yields benefits as well as complications. A multidisciplinary management including a nutritionist, an obstetrician, an anesthesiologist, and a bariatric surgeon is required. The aim of this review is to analyze the impact of bariatric surgery on pregnancy and vice versa, and to identify the key points of this management.