Pregnancy outcomes in women with bariatric surgery as compared with morbidly obese women

The impact of bariatric surgery on maternal and neonatal health: a systematic review and meta-analysis

BACKGROUND

Maternal obesity increases the risk of neonatal and maternal complications. Although the weight-loss benefits of bariatric surgery are well established, the effects on subsequent pregnancies, particularly regarding timing of pregnancy after surgery, are not yet fully understood OBJECTIVES: To evaluate the impact of bariatric surgery on weight-related, maternal, and neonatal outcomes in subsequent pregnancies, focusing on the timing of pregnancy after surgery.

SETTING

A systematic review and meta-analysis was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PROSPERO ID: CRD42024570170).

METHODS

The systematic review process identified 129 studies eligible for inclusion involving 227,792 women who became pregnant after bariatric surgery. Data were analyzed for body mass index (BMI) changes, gestational age, and neonatal birth weight.

RESULTS

Prepregnancy BMI reduced by 13.93 kg/m2 (P < .001) compared with presurgery BMI. There was no significant change in BMI throughout the antenatal period against non-bariatric surgery controls. Neonatal birth weight was 257.8 g lower (P < .001) in patients who had previously undergone bariatric surgery. There was no significant difference in neonatal birth weight (-69.41 g, P = .152) or gestational age (-.749 d, P = .826) in patients who became pregnant fewer than 18 months after surgery and those who became pregnant greater than 18 months after surgery.

CONCLUSIONS

Bariatric surgery successfully reduced maternal BMI before pregnancy but lowered neonatal birth weight, indicating the need for careful fetal monitoring. The timing of pregnancy after surgery appears flexible, with no significant impact on gestational age or birth weight, suggesting that clinical management should focus on individualized nutritional and health monitoring rather than fixed guidelines.

Conceiving during the first postoperative year after bariatric surgery: a retrospective study of pregnancy outcomes

BACKGROUND

An increasing number of childbearing-aged women have undergone bariatric surgery (BS). Although pregnancy outcomes generally improve after BS, concern remains over the impact of rapid weight loss and the catabolic state that occurs soon after BS. At least a 12-month surgery-to-conception time (SCT) is recommended, though the reasoning behind this has been questioned. This retrospective study was conducted to compare post-BS pregnancies with SCTs of less (Group 1) or more (Group 2) than 12 months.

METHODS

The Hospital Register and Finnish Medical Birth Register were queried for data on BS and subsequent pregnancies. The characteristics of women at surgery and maternal and newborn outcomes in post-BS pregnancies were collected.

RESULTS

Between 2010 and 2022, 113 women gave birth after BS. This included 17 and 96 patients in Groups 1 and 2. The mean SCTs were 8.0 ± 2.7 and 39.0 ± 24.3 months (p < 0.001), respectively. At BS, the characteristics of age (p = 0.316), weight (p = 0.718), body mass index (BMI) (p = 0.114) and surgical technique used (p = 0.648) were similar. During pregnancy, the mean age of Group 1 women was significantly lower (p = 0.005). With no difference in weight (p = 0.961) or BMI (p = 0.567), the incidence of gestational diabetes mellitus (GDM, p = 0.039) was higher in Group 2. The mean gestational age at delivery (p = 0.206) and incidence rates of preterm (p = 0.645), post-term (p = 1.00) and caesarean deliveries (p = 1.00) in the groups were similar. A significantly higher incidence of delivery induction (p < 0.001 was detected in Group 2. The mean newborn weight in Group 1 was lower (p = 0.038), but the mean birth weight standard deviation (p = 0.883) and incidences of low birth weight (< 2500 g, p = 0.345) and small-for-gestational-age newborns (p = 0.469) were similar. The 1- (p = 0.191) and 5-min (p = 0.174) Apgar points in the groups were similar, and no associations between pregnancy outcomes and surgery technique were detected.

CONCLUSIONS

The outcome in pregnancies with an SCT 12 months, postponing pregnancy may not always improve pregnancy outcomes. Therefore, all risks should be weighed when counselling women regarding the optimal time of pregnancy after BS.

The effect of bariatric surgery on polycystic ovary syndrome patients' obstetric and neonatal outcomes: a population-based study

PURPOSE

To examine the effect of bariatric surgery (BS) on obstetric and neonatal outcomes in patients with polycystic ovary syndrome (PCOS).

METHODS

A retrospective population-based cohort study utilizing the Healthcare Cost and Utilization Project Nationwide Inpatient Sample database, including women who delivered in the third trimester or had a maternal death in the USA (2004-2014). We compared obstetric and neonatal outcomes between groups in three analyses: (1) Primary analysis-women with an ICD-9 PCOS diagnosis who underwent BS compared to pregnant PCOS patients without BS. (2) Sub-group analysis-PCOS women with BS compared to obese PCOS women (body mass index (BMI) ≥ 30 kg/m2) without BS. (3) Women with and without PCOS who underwent BS.

RESULT

In the primary analysis, pregnant PCOS women who underwent BS (N = 141), compared to pregnant PCOS women without BS (N = 14,741), were less likely to develop pregnancy-induced hypertension (PIH) (9.2% vs. 16.2%, respectively, aOR 0.39, 95% CI 0.21-0.72) and gestational diabetes mellitus (GDM) (9.9% vs. 18.8, aOR 0.40, 95% CI 0.23-0.70). In the sub-group analysis, PCOS women with BS, compared to obese PCOS women without BS (N = 3231), were less likely to develop gestational hypertension, preeclampsia, and preeclampsia or eclampsia superimposed on hypertension (P < 0.05). Lastly, PCOS patients with BS had a higher cesarean section rate when compared to non-PCOS patients with BS (N = 9197) (61.7% vs. 49.2%, aOR 1.48, 95% CI 1.05-2.09), with otherwise comparable obstetric and neonatal outcomes.

CONCLUSIONS

BS in PCOS patients was associated with reduced risks for GDM and PIH when compared to PCOS controls without BS and reduced risk for gestational hypertension, preeclampsia, and preeclampsia or eclampsia superimposed on hypertension when compared to obese PCOS controls without BS. Moreover, BS was associated with reduced inherent pregnancy risks of PCOS, almost equating them to those of non-PCOS counterparts.

Beyond Weight Loss: A Comprehensive Review of Pregnancy Management following Bariatric Procedures

The increasing prevalence of bariatric surgery among women of childbearing age raises critical questions about the correct management of pregnancy following these procedures. This literature review delves into the multifaceted considerations surrounding pregnancy after bariatric surgery, with a particular focus on the importance of preconception counselling, appropriate nutrition assessment, and the necessity of correct folic acid supplementation. Key areas of investigation include nutrient absorption challenges, weight gain during pregnancy, and potential micronutrient deficiencies. Examining the relationship between bariatric surgery and birth defects, particularly heart and musculoskeletal issues, uncovers a twofold increase in risk for women who underwent surgery before pregnancy, with the risk emphasized before folic acid fortification. In contrast, a nationwide study suggests that infants born to mothers with bariatric surgery exhibit a reduced risk of major birth defects, potentially associated with improved glucose metabolism. In addition, this review outlines strategies for managing gestational diabetes and other pregnancy-related complications in individuals with a history of bariatric surgery. By synthesizing existing literature, this paper aims to provide healthcare providers with a comprehensive framework for the correct management of pregnancy in this unique patient population, promoting the health and well-being of both mother and child.

[Effect of gestational weight gain in a cohort of pregnancy women with obesity operated and not operated for bariatric surgery]

Introduction

Objective: to determine the effect of gestational weight gain and perinatal outcomes in obese women who underwent and did not undergo bariatric surgery. Material and methods: a retrospective observational cohort study was conducted. The gestational weight gain was classified as insufficient, adequate or excessive according to the guidelines of the United States Institute of Medicine: 4.99-9.07 kg for body mass index (BMI) > 30 kg/m2. Weight gain was calculated as the difference between the weight at the first visit of the 1st trimester and the weight at the visit of the 3rd trimester. Outcomes examined included antepartum variables (gestational diabetes, gestational hypertension, preeclampsia, premature rupture of membranes, placenta previa, placental abruption, intrauterine growth retardation, chorioammionitis, spontaneous abortion), intrapartum variables (induced delivery, vaginal delivery, vacuum, forceps delivery, cesarean section, shoulder dystocia), postpartum variables (postpartum hemorrhage, need for postpartum transfusion, postpartum anemia, need for emergency care, maternal death, postpartum tear, postpartum thrombosis) and neonatal variables (preterm delivery, weight percentile > 90, weight percentile < 10, Apgar score < 7, malformations). Using the statistical package SPSS 22.0, a statistical analysis of the data was performed. Results: two hundred and fifty-six women were recruited; 38 (14.58 %) were pregnant after bariatric surgery and 218 (85.15 %) were pregnant women with obesity who had not been operated on. Of the pregnant women with obesity who had not been operated on, 119 (46.68 %) had grade 1 obesity (BMI 30-34.9), and 99 (38.67 %) had grade 2 and 3 obesity (BMI > 35). A global and subgroup analysis was performed. In the overall analysis, 78 (30.46 %) had insufficient gain, 117 (45.70 %) had adequate gain, and 61 (23.82 %) excessive gain. Overall, insufficient weight gain was associated with a lower probability of gestational hypertension (p < 0.015) and forceps delivery (p < 0.000) and large for gestational age newborn (p < 0.000). On the other hand, insufficient weight gain was associated with a higher probability of intrauterine growth retardation (p 0.044), peripartum infection (0.022), preterm delivery (0.006), and delivery < 35 weeks (p 0.016). Excessive weight gain was associated with a higher probability of gestational hypertension (p 0.025), induced labor (p 0.009), forceps delivery (p 0.011) and large for gestational age newborn (p 0.006). Pregnancies after bariatric surgery had fewer overall complications compared to the other groups. Conclusions: insufficient and excessive weight gain worsens perinatal outcomes. Adequate weight gain does not increase complications and produces some benefits.

Pregnancy characteristics and outcomes after bariatric surgery: national-level analysis in the United States

BACKGROUND

Bariatric surgery is an effective surgical treatment for weight reduction in individuals with obesity. Pregnancy outcomes related to prior bariatric surgery are currently under active investigation.

OBJECTIVE

To assess national-level trends, characteristics, and outcomes of pregnancy after bariatric surgery in the United States.

SETTING

Retrospective cohort study queried the National Inpatient Sample.

METHODS

The study population was 14,648,135 patients who had vaginal or cesarean delivery from January 2016 to December 2019. Exposure allocation was based on the history of bariatric surgery. The main outcomes were (1) trends and characteristics related to bariatric surgery, assessed with multivariable binary logistic regression model; and (2) Centers for Disease Control and Prevention-defined severe maternal morbidity, assessed by propensity score matching and generalized estimating equation.

RESULTS

A total of 53,950 (.4%) patients had prior bariatric surgery. The number of patients with prior bariatric surgery increased from .3% to .5%, and this trend remained independent in multivariable analysis (P < .001). Patients who had bariatric surgery were also more likely to be older and have obesity, medical co-morbidities, fetal growth restriction, preterm birth, and cesarean delivery compared with those without bariatric surgery (all, P < .05). In a propensity score matched model, patients who had bariatric surgery were more likely to receive blood product transfusion (2.3% versus 1.6%; odds ratio = 1.45; 95% confidence interval, 1.19-1.77), but severe maternal morbidity other than blood product transfusion was comparable to those without (1.1% versus 1.4%; odds ratio = .80; 95% confidence interval, .63-1.02).

CONCLUSION

There is a gradual increase of pregnancy after bariatric surgery in recent years in the United States.

A Multi-Ingredient Supplement Protects against Obesity and Infertility in Western Diet-Fed Mice

The Western diet (WD) predisposes to bodyweight gain and obesity and is linked to mitochondrial dysfunction, oxidative damage, inflammation, and multisystem disease, even affecting the reproductive organs, fertility, and pregnancy outcomes. In this study, we investigated the effects of multi-ingredient supplementation (MIS) with antioxidants, phytonutrients, and vitamins ('Fertility Enhancer'; FE) on white adipose tissue (WAT) expansion, nonalcoholic fatty liver disease (NAFLD), and infertility in WD-fed C57BL/6J mice. Five-month-old male (M) and female (F) mice were fed a low-fat diet (LF) or a high fat/sucrose WD (HF) for six weeks, followed by six weeks of LF (3.64 kcal/g), HF (4.56 kcal/g), or HF combined with FE (4.50 kcal/g). A sub-set of animals were sacrificed at 12 weeks, while the remainder were harem-mated in a 1:2 male-to-female ratio, and singly housed during the gestational period. Two-way, factorial ANOVA analysis revealed a main effect of diet on bodyweight (BW), total body fat, % body fat, white adipose tissue mass, and liver lipid content (all p < 0.001), driven by the anti-obesogenic effects of the 'Fertility Enhancer'. Similarly, a main effect of diet was found on PGC1-α mRNA levels (p < 0.05) and mitochondrial protein content (p < 0.001) in perigonadal WAT, with PGC1-α induction and higher complex II and complex III expression in FE vs. HF animals. Copulatory plug counts were higher in FE vs. HE couples (30% vs. 6%), resulting in more litters (4 vs. 0) and higher copulatory success (67% vs. 0%). Although the trends of all histology outcomes were suggestive of a benefit from the FE diet, only the number of atretic follicles and testicular mass were significant. Ovarian IL-1β mRNA induction was significantly attenuated in the FE group (p < 0.05 vs. HF) with CASP1 attenuation trending lower (p = 0.09 vs. HF), which is indicative of anti-inflammatory benefits of the 'Fertility Enhancer.' We conclude that supplementation with specific phytonutrients, antioxidants, and vitamins may have utility as an adjunctive therapy for weight management, fatty liver disease, and infertility in overweight and obese couples.

Pregnancy Complications in Women with Weight Loss Surgery Compared to a Non-Surgical Population of Women with Obesity

BACKGROUND

The objective of this study was to assess the effect of WLS on pregnancy and delivery complications in women who had WLS compared to women with obesity who did not undergo WLS.

METHODS

We used the National Inpatient Sample data from 2012 to 2017, with a study population of women between the ages of 20 and 44 who had a maternal admission code in the NIS data (n = 663,795). Weighted logistic regression models were fitted and the models were stratified by race. Covariates included age, race, primary payer, previous cesarean delivery, physical health comorbidities, and depression.

RESULTS

There were decreased odds of gestational diabetes in women of all races (aORall = 0.47, 95% CIall = 0.44-0.49). There were decreased odds for gestational hypertension in women of all races (aORall = 0.55, 95% CIall = 0.51-0.59). Compared to women who did not have WLS, there were lower odds of cesarean delivery among women with a history of WLS (aORall = 0.62, 95% CIall = 0.60-0.65), which was true for White women, Black women, and Latinas with a history of WLS (aORWhite = 0.57, 95% CIWhite = 0.53-0.60; aORBlack = 0.67, 95% CIBlack = 0.61-0.74; aORLatina = 0.71, 95% CILatina = 0.64-0.78).

CONCLUSIONS

Overall, women with history of WLS had lower odds of most of the pregnancy outcomes (gestational diabetes, gestational hypertension, pre-eclampsia/eclampsia, and cesarean delivery) with results mediated by race.

Nutrition for pregnancy after metabolic and bariatric surgery: literature review and practical guide

When pregnancy follows metabolic and bariatric surgery (MBS), there are many important considerations related to nutritional status that may impact maternal and infant outcomes. Although evidence-based nutrition guidelines for pregnancy exist for the general population, there are limited practical recommendations that specifically address pregnancy after MBS. A literature search was conducted to investigate outcomes of women with a history of MBS and pregnancy. Search criteria focused on women 18 years of age and older who became pregnant after MBS. Search terms included "laparoscopic sleeve gastrectomy," "Roux-en-Y gastric bypass," "laparoscopic adjustable gastric banding," "biliopancreatic duodenal switch," and gestation terminology, and they were paired with the nutrition outcomes of interest. A total of 167 publications were identified; 46 articles were included in the final review. Data relating to gestation and fetal weight and nutrition and cardiometabolic data were extracted from the studies. Based on this review, women of childbearing age with a history of MBS should be evaluated and monitored for nutritional status before conception, during pregnancy, and postpartum.

Pregnancy after bariatric surgery: Effects of personalized nutrition counseling on pregnancy outcomes

BACKGROUND & AIMS

Nutritional challenges following bariatric surgery can be intensified during pregnancy and may have crucial effects on the fetus, including lower birth weight. To the best of our knowledge, the effect of nutritional counseling during post-bariatric pregnancy to improve maternal diet quality and eating habits on neonatal outcome has not been evaluated. The aim of this research was to examine the effects of personal nutritional counseling during post-bariatric pregnancy on nutritional intake and neonatal outcomes.

METHODS

We performed a non-randomized, intervention-control clinical trial. Women (n = 61) were divided into three groups; two prospective, and one retrospective: 1. An Intervention Bariatric Prospective group 2. A Control Prospective group without surgery, and 3. A Control Bariatric Retrospective group. Patient enrollment was performed from April 2016 to March 2018. The intervention program included biweekly visits with a pregnancy nutrition certified bariatric dietitian. Data collection was performed four times during pregnancy, and included demographic and eating habits questionnaires, 24 h dietary recall, and information about delivery outcomes. In the retrospective group delivery outcomes and Food Frequency Questionnaire was collected once, after delivery.

RESULTS

There were no differences between groups at baseline except for a higher pre-pregnancy BMI in the post-bariatric groups. In the prospective groups, dietary protein, energy, and iron were found to be consumed in higher amounts in the Control-Prospective group than in the Intervention Bariatric-Prospective group (p < 0.05), without the addition of supplements. On the other hand, iron and calcium calculated from diet with supplements, were found to be significantly higher in the Intervention Bariatric Prospective group than in the Control Prospective group. In addition, consumption of saturated fats, oil, and salty snacks was lower in both prospective groups compared to the retrospective group (p < 0.05), suggesting better food quality habits for the bariatric group with nutritional counseling. Mean birth weight was significantly lower in the Control Bariatric Retrospective group than in the Control-Prospective group (3074 ± 368 g vs. 3396 ± 502 g, respectively. p = 0.023). In the Intervention Bariatric Prospective group, mean birth weight was 3168 ± 412 g, and no significant difference was observed from the Control Prospective group. Birth percentiles were also significantly lower in the Control Bariatric Retrospective group compared to the Control Prospective group (27th vs. 42nd, respectively. p < 0.05). In the Intervention Bariatric Prospective group, mean birth percentile was 35th, and no significant difference was observed from the Control Prospective group. As for the weight change of the woman during pregnancy, the highest variability was noted among the Control Bariatric Retrospective group with cases of weight loss up to 37 kg, due to conception close to the bariatric operation. Nevertheless, this variable was controlled, and showed no significant impact on birth weight results.

CONCLUSIONS

Our results suggest that personalized nutritional counseling care during post bariatric pregnancy improved nutrient intake of mothers and may contribute to higher birth weight of offspring. Further research is needed to examine the effects of prenatal nutrition care intervention, in addition to repeating this trial with a larger sample size, to allow for clearer findings.

CLINICAL TRIAL REGISTRATION

IRB number: 0310-15-RMB.

IDENTIFICATION NIH NUMBER

NCT02697981 URL: https://www.nih.gov.

Maternal and neonatal outcomes in women undergoing Roux-en-Y gastric bypass: A systematic review and meta-analysis

BACKGROUND

To summarize evidence of benefits and risks of maternal and neonatal outcomes among pregnant women after Roux-en-Y gastric bypass surgery.

METHODS

A systematic search was conducted in MEDLINE, EMBASE, Web of Science, Ovid and Cochrane Library until 24th May 2021. Inclusion criteria were randomized trails or observational studies including at least one of maternal or neonatal outcomes from pregnant women who had a history of Roux-en-Y gastric bypass surgery with a control group of pregnant women with no history of bariatric surgery. Non-English studies were excluded. Both fixed-effect and random-effect models were used in the meta-analyses. Newcastle-Ottawa Scale was used to assess quality of studies.

RESULTS

Nine retrospective articles were eligible including 13 848  pregnant women with a history of Roux-en-Y gastric bypass surgery and 255 008 pregnant women without a history of bariatric surgery. The results of meta-analysis showed a lower incidence of preterm premature rupture of membranes (OR 0.53, 95% CI [0.47, 0.60], p < 0.00001), large gestational age infants (OR 0.28, 95%CI [0.22, 0.37], p < 0.00001) or macrosomia (OR 0.26, 95%CI [0.23, 0.30], p < 0.00001) in women after Roux-en-Y gastric bypass surgery. On the other hand, infants born to mothers with a history of Roux-en-Y gastric bypass surgery had an increased risk of small gestational age (OR 2.24, 95% CI [1.55, 3.24], p ＜ 0.00001).

CONCLUSION

Roux-en-Y gastric bypass surgery reduces significantly of risks of preterm premature rupture of membranes and large for gestational age/ macrosomia, but increase the risk of small for gestational age.

Severe maternal morbidity and mortality during delivery hospitalization of class I, II, III, and super obese women

BACKGROUND

Previous studies show that obesity predisposes patients to higher risks of adverse pregnancy outcomes. Data on the relationship between increasing degrees of obesity and risks of severe maternal morbidity, including mortality, are limited.

OBJECTIVE

We examined the association of increasing classes of obesity, especially super obesity, with the risk of severe maternal morbidity and mortality at the time of delivery hospitalization.

STUDY DESIGN

Using New York City linked birth certificates and hospital discharge data, we conducted a retrospective cohort study. This study identified delivery hospitalizations for singleton, live births in 2008-2012. Women were classified as having obesity (class I, II, III, or super obesity), as opposed to normal weight or overweight, based on prepregnancy body mass index. Cases of severe maternal morbidity were identified based on International Classification of Diseases, Ninth Revision diagnosis and procedure codes according to Centers for Disease Control and Prevention criteria. Multivariable logistic regression was used to evaluate the association between obesity classes and severe maternal morbidity, adjusting for maternal sociodemographic characteristics.

RESULTS

During 2008-2012, there were 570,997 live singleton births with available information on prepregnancy body mass index that met all inclusion criteria. After adjusting for maternal characteristics, women with class II (adjusted odds ratio, 1.14; 95% confidence interval, 1.05-1.23), class III (adjusted odds ratio, 1.34; 95% confidence interval, 1.21-1.49), and super obesity (adjusted odds ratio, 1.99; 95% confidence interval, 1.57-2.54) were all significantly more likely to have severe maternal morbidity than normal and overweight women. Super obesity was associated with specific severe maternal morbidity indicators, including renal failure, air and thrombotic embolism, blood transfusion, heart failure, and the need for mechanical ventilation.

CONCLUSION

There is a significant dose-response relationship between increasing obesity class and the risk of severe maternal morbidity at delivery hospitalization. The risks of severe maternal morbidity are highest for women with super obesity. Given that this is a modifiable risk factor, women with prepregnancy obesity should be counseled on the specific risks associated with pregnancy before conception to optimize their pregnancy outcomes.

Risk of Severe Maternal Morbidity After Bariatric Surgery: Retrospective Cohort Study

OBJECTIVE

We assessed whether bariatric surgery before pregnancy lowers the risk of severe maternal morbidity to a level comparable to no obesity.

SUMMARY OF BACKGROUND DATA

Obesity is a risk factor for severe maternal morbidity, but the potential for bariatric surgery to reduce the risk has not been studied.

METHODS

We analyzed a retrospective cohort of 2,412,075 deliveries between 1989 and 2019 in Quebec, Canada. The main exposure measures were bariatric surgery before pregnancy and obesity without bariatric surgery, compared with no obesity. The outcome was severe maternal morbidity, a composite of life-threatening pregnancy complications. We estimated risk ratios (RR) and 95% confidence intervals (CI) for the association between bariatric surgery and severe maternal morbidity, adjusted for maternal characteristics.

RESULTS

A total of 2654 deliveries (0.1%) were in women who had bariatric surgery, and 70,041 (29.0 per 1000) were in women who had severe maternal morbidity. Risk of severe maternal morbidity was not significantly elevated for bariatric surgery (RR 1.20; 95% CI 0.98-1.46), but was greater for obesity compared with no obesity (RR 1.60; 95% CI 1.55-1.64). Bariatric surgery was not associated with morbidities such as severe preeclampsia, sepsis, and cardiac complications compared with no obesity, but obesity was associated with elevated risks of these and other severe morbidities. Bariatric surgery was associated, however, with intensive care unit admission, compared with no obesity.

CONCLUSIONS

Pregnant women with prior bariatric surgery have similar risks as nonobese women for most types of severe maternal morbidity, except for intensive care unit admission.

Neonatal Outcomes of Pregnancy Following Roux-en-Y Gastric Bypass: a Matched Case-Control Study

PURPOSE

To compare perinatal outcomes and to assess the predictors of birth weight (BW) after Roux-en-Y gastric bypass (RYGB) to those women unexposed to bariatric surgery.

MATERIALS AND METHODS

Singleton births from women submitted to RYGB (BSG) were matched to two control births by maternal age, delivery year, and gender. Control group 1 (CG1) and control group 2 (CG2) were selected according to the prepregnancy body mass index (BMI) < 35 kg/m² and ≥ 35 kg/m², respectively, without previous bariatric surgery.

RESULTS

Fifty-eight pregnancies were evaluated in each group (n = 174). Neonates born after RYGB presented lower BW compared to CG1 (mean difference - 182.3 g; 95% CI - 333; - 31, P = 0.018) and CG2 (mean difference - 306.6 g, 95% CI - 502; - 111, P = 0.02). Although gestational age (GA) was similar (P = 0.219), fetal growth rate (in grams) per gestational week was higher in CG2 (β = 196.27, P < 0.001) vs. BSG (β = 127.65, P < 0.001), irrespective of gestational weight gain (GWG). Pregnancies post-RYGB showed lower GWG, lower BW, and higher prevalence of cesarean section than CG1 and were associated with lower BW, smaller cephalic perimeter, lower prevalence of macrosomia, hypertension, and gestational diabetes than CG2.

CONCLUSION

Birth weight was higher in neonates from women with higher prepregnancy BMI, as compared to births from women submitted to RYGB, irrespective of GWG. Although nearly half of the RYGB mothers were classified with obesity at conception, those pregnancies were associated with better obstetric and neonatal outcomes than among women with prepregnancy BMI ≥ 35 kg/m² who had never undergone RYGB.

Ghrelin signalling is dysregulated in male but not female offspring in a rat model of maternal vertical sleeve gastrectomy

Bariatric surgery is the most effective and durable means of treating obesity and its comorbidities. Women make up 80% of those receiving weight loss surgery and they experience improvements in fertility. Unfortunately, bariatric surgery in the context of pregnancy is associated with complications, including growth restriction and small-for-gestational age offspring (SGA). SGA offspring have a greater risk for obesity in adulthood, although the mechanism for this SGA-induced obesity is unknown. In a rat model of vertical sleeve gastrectomy (VSG), we previously identified reductions during pregnancy in ghrelin, a stomach-derived hormone that increases appetite and induces growth hormone secretion. Here, we hypothesise that VSG offspring will have altered ghrelin signalling compared to offspring of Sham dams as a result of reduced in utero ghrelin. At postnatal day (PND)21, male and female offspring of dams that have previously received VSG have an increase in mRNA expression for the ghrelin receptor in the hypothalamus compared to Sham offspring, and the expression of GOAT is lower in females compared to males. Liver expression of endogenous ghrelin antagonist, LEAP2, is elevated at PND60 in VSG offspring. Expression of other genes in the growth hormone system (growth hormone-releasing hormone and growth hormone) were not altered. Plasma levels of total ghrelin at PND21 are also not different between VSG and Sham pups. In adult pups, 1-hour chow intake of male but not female VSG offspring given is less than Sham offspring when given 50 µg kg-1 of exogenous ghrelin by i.p. injection. These results indicate that maternal VSG surgery has an impact on ghrelin signalling in offspring and that, as adults, male VSG offspring may be functionally less responsive to ghrelin than controls.

Guideline No. 391-Pregnancy and Maternal Obesity Part 1: Pre-conception and Prenatal Care

OBJECTIVE

This guideline will review key aspects in the pregnancy care of women with obesity. Part I will focus on pre-conception and pregnancy care. Part II will focus on team planning for delivery and Postpartum Care.

INTENDED USERS

All health care providers (obstetricians, family doctors, midwives, nurses, anaesthesiologists) who provide pregnancy-related care to women with obesity.

TARGET POPULATION

Women with obesity who are pregnant or planning pregnancies.

EVIDENCE

Literature was retrieved through searches of Statistics Canada, Medline, and The Cochrane Library on the impact of obesity in pregnancy on antepartum and intrapartum care, maternal morbidity and mortality, obstetrical anaesthesia, and perinatal morbidity and mortality. Results were restricted to systematic reviews, randomized controlled trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated in the guideline to September 2018. Grey (unpublished) literature was identified through searching the websites of health technology assessment and related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALIDATION METHODS

The content and recommendations were drafted and agreed upon by the authors. Then the Maternal-Fetal Medicine Committee peer reviewed the content and submitted comments for consideration, and the Board of the Society of Obstetricians and Gynaecologists of Canada (SOGC) approved the final draft for publication. Areas of disagreement were discussed during meetings, at which time consensus was reached. The level of evidence and quality of the recommendation made were described using the Evaluation of Evidence criteria of the Canadian Task Force on Preventive Health Care.

BENEFITS, HARMS, AND COSTS

Implementation of the recommendations in these guidelines may increase obstetrical provider recognition of the issues affected pregnant individuals with obesity, including clinical prevention strategies, communication between the health care team, the patient and family as well as equipment and human resource planning. It is hoped that regional, provincial and federal agencies will assist in the education and support of coordinated care for pregnant individuals with obesity.

GUIDELINE UPDATE

SOGC guidelines will be automatically reviewed 5 years after publication. However, authors can propose another review date if they feel that 5 years is too short/long based on their expert knowledge of the subject matter.

SPONSORS

This guideline was developed with resources funded by the SOGC.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Pregnancy After Bariatric Surgery: a Comparative Study of Post-Bariatric Pregnant Women Versus Non-Bariatric Obese Pregnant Women

PURPOSE

To evaluate the impact of bariatric surgery on the gestational outcomes.

MATERIALS AND METHODS

Retrospective study of pregnant women hospitalized for delivery in the maternity in Curitiba, Brazil, who had a body mass index (BMI) greater than or equal to 30 kg/m² and/or who had undergone bariatric surgery. Interviews were performed, and the patients' medical records and antenatal information cards were evaluated.

RESULTS

Ninety-three pregnant women who had bariatric surgery and 205 obese pregnant women were selected. A lower occurrence of hypertensive diseases was observed in pregnant women who had undergone bariatric surgery (14%) compared with obese pregnant women (56.6%). Moreover, a reduced occurrence of diabetes was found in post-bariatric pregnant women (16.1%) compared with obese pregnant women (30.2%). There were no differences in the frequency of prematurity, in delivery methods, or in postpartum complications. There was a higher number of cases of babies who were small for gestational age and a lower number of babies who were large for gestational age in the post-bariatric group. When comparing obese pregnant women to post-bariatric pregnant women who had remained obese, a reduced frequency of hypertensive diseases and diabetes was found in the latter group, but the weight difference between their newborns was not statistically significant.

CONCLUSION

There was a lower occurrence of health-related issues complicating pregnancy among women who had undergone bariatric surgery, but these women's newborns were more likely to be small for gestational age, a finding which was less significant the less weight the mother had lost.

Review: Sex-Specific Aspects in the Bariatric Treatment of Severely Obese Women

This systematic literature review aims to point out sex-specific special features that are important in the bariatric treatment of women suffering from severe obesity. A systematic literature search was carried out according to Cochrane and Preferred Reporting Items for Systematic review and Meta-Analysis Protocols (PRISMA-P) guidelines. After the literature selection, the following categories were determined: sexuality and sexual function; contraception; fertility; sex hormones and polycystic ovary syndrome; menopause and osteoporosis; pregnancy and breastfeeding; pelvic floor disorders and urinary incontinence; female-specific cancer; and metabolism, outcome, and quality of life. For each category, the current status of research is illuminated and implications for bariatric treatment are determined. A summary that includes key messages is given for each subsection. An overall result of this paper is an understanding that sex-specific risks that follow or result from bariatric surgery should be considered more in aftercare. In order to increase the evidence, further research focusing on sex-specific differences in the outcome of bariatric surgery and promising treatment approaches to female-specific diseases is needed. Nevertheless, bariatric surgery shows good potential in the treatment of sex-specific aspects for severely obese women that goes far beyond mere weight loss and reduction of metabolic risks.

Altered immune system in offspring of rat maternal vertical sleeve gastrectomy

Obesity in women results in reduced fertility and increased complications during pregnancy. Vertical sleeve gastrectomy (VSG) effectively reduces weight, type 2 diabetes, and dyslipidemia, but is also associated with preterm and small-for-gestational age births. The mechanism by which VSG influences fetal development remains unknown. Here we hypothesize that previously reported immune changes during rat VSG pregnancy are reflected long term in the immune system of the offspring. Offspring of VSG and sham dams were evaluated at postnatal day (PND) 21 and PND60. At PND21, VSG pups have lower numbers of circulating B lymphocytes compared with sham pups (P < 0.05) and have lower transcription of lymphocyte marker Ptprc (P < 0.01) in the spleen, while other lymphocyte populations measured are not different. Total plasma IgG is higher (P < 0.01) and C-reactive protein is lower (P < 0.05) in VSG offspring compared with sham offspring at PND21. The central nervous system of VSG pups is also affected at PND21, having higher expression of Il1b mRNA (P < 0.05) and higher immunoreactivity of microglia marker, IBA1, in the hypothalamus. At PND60, the immune-hematological differences are not present; however, mRNA expression of Il1b is elevated (P < 0.001) in the spleen of VSG offspring along with markers of T cells. These data suggest that the immune system of VSG offspring is compromised early in life, but rebounds after weaning and may even become hyperactive. Future work is needed to determine whether the immune system of VSG offspring is capable of mounting a proper defense and whether other aspects of development are affected.

Bariatric surgery and the risk of congenital anomalies in subsequent pregnancies

BACKGROUND

Data on the relationship between bariatric surgery and risk of birth defects are conflicting.

OBJECTIVES

We studied the association of bariatric surgery with birth defects in future pregnancies in a large cohort of women.

METHODS

We carried out a retrospective cohort study of 2,194,348 pregnancies that occurred between 1989 and 2016 in Quebec, Canada. We identified women who had bariatric surgery before pregnancy, and included nonobese women with no surgery as a comparison group. We estimated risk ratios (RRs) and 95% CIs for the associations between bariatric surgery and the risk of birth defects, using log-binomial regression models adjusted for maternal age, comorbidities, parity, whether there was a multiple birth, socioeconomic deprivation, and the presence of folic acid food fortification.

RESULTS

In this study, 1845 deliveries were among women who had bariatric surgery before pregnancy (0.08%). Having bariatric surgery was associated with 1.20 times the risk of birth defects in later pregnancies (95% CI: 1.01, 1.43), compared with having no surgery or obesity. Obesity without having bariatric surgery was, in contrast, more weakly associated with birth defects (RR: 1.09; 95% CI: 1.07, 1.12). The association with bariatric surgery was greater for heart (RR: 1.47; 95% CI: 1.02, 2.12) and musculoskeletal defects (RR: 1.32; 95% CI: 1.02, 1.71). Associations were primarily present before folic acid food fortification was implemented (RR: 2.03; 95% CI: 1.41, 2.92), but not after (RR: 1.05; 95% CI: 0.86, 1.28).

CONCLUSIONS

Having bariatric surgery was a risk factor for birth defects, and particularly heart and musculoskeletal defects. After fortification, however, an association was no longer present. Future studies are needed to determine whether micronutrient supplementation underpins the difference in the changing results pre- and postfortification.

Bariatric surgery and birth defects: A systematic literature review

BACKGROUND

Bariatric procedures are on the rise. The risk of birth defects in pregnancies following such procedures may be increased (eg, due to nutrient deficiencies) or decreased (eg, due to decreased maternal body mass index, BMI).

METHODS

We conducted a systematic literature review of the association between bariatric surgery and birth defects using Ovid MEDLINE and PubMed (1946-2017). Information was abstracted on study design, exposures, outcomes, covariates and estimates of association.

RESULTS

Fifteen studies met our inclusion criteria: 14 evaluated the outcome of any birth defect, and one evaluated neural tube defects. Estimates of association between bariatric surgery and birth defects were available for nine studies and ranged from 0.6 to 1.9 (all 95% confidence intervals included 1.0). When studies were stratified by surgery type, there was no obvious pattern of association. When stratified by the approach used to account for BMI, positive associations were observed in studies that did not account for maternal prepregnancy BMI or used women with normal BMI as the reference group (range: 1.3-1.9). Estimates from studies that either matched or adjusted for prepregnancy BMI were closer to the null (range: 1.1-1.2) and studies that compared to morbidly obese women reported protective associations (range: 0.6-0.7).

CONCLUSIONS

Studies of the association between bariatric surgery and birth defects vary with respect to the surgical procedures included, birth defects ascertainment methods and approaches used to account for maternal BMI. Consequently, it is not possible to draw a conclusion regarding the association between bariatric surgery and birth defects. Additional studies are warranted.

Screening and Management of Gestational Diabetes Mellitus after Bariatric Surgery

Gestational diabetes mellitus (GDM) is a frequent medical complication during pregnancy. This is partly due to the increasing prevalence of obesity in women of childbearing age. Since bariatric surgery is currently the most successful way to achieve maintained weight loss, increasing numbers of obese women of childbearing age receive bariatric surgery. Bariatric surgery performed before pregnancy significantly reduces the risk to develop GDM but the risk is generally still higher compared to normal weight pregnant women. Women after bariatric surgery therefore still require screening for GDM. However, screening for GDM is challenging in pregnant women after bariatric surgery. The standard screening tests such as an oral glucose tolerance test are often not well tolerated and wide variations in glucose excursions make the diagnosis difficult. Capillary blood glucose measurements may currently be the most acceptable alternative for screening in pregnancy after bariatric surgery. In addition, pregnant women after bariatric surgery have an increased risk for small neonates and need careful nutritional and foetal monitoring. In this review, we address the risk to develop GDM after bariatric surgery, the challenges to screen for GDM and the management of women with GDM after bariatric surgery.

Delivery outcomes in term births after bariatric surgery: Population-based matched cohort study

BACKGROUND

Obesity increases the risk of adverse delivery outcomes. Whether weight loss induced by bariatric surgery influences these risks remains to be determined. The objective was to investigate the risk of adverse delivery outcomes among post-surgery women compared with women without bariatric surgery history but with similar characteristics.

METHODS AND FINDINGS

We identified 801,443 singleton live-born term births (≥37 gestational weeks) in the Swedish Medical Birth Register between 1 January 2006 and 31 December 2013, of which 1,929 were in women with a history of bariatric surgery and a pre-surgery weight available from the Scandinavian Obesity Surgery Registry. For each post-surgery delivery, up to 5 control deliveries were matched by maternal pre-surgery BMI (early-pregnancy BMI used for controls), age, parity, smoking, education, height, country of birth, and delivery year (N post-surgery deliveries:matched controls = 1,431:4,476). The main outcome measures were mode of delivery, induction of labor, post-term pregnancy (≥42 + 0 gestational weeks), epidural analgesia, fetal distress, labor dystocia, peripartum infection, obstetric anal sphincter injury (perineal tear grade III-IV), and postpartum hemorrhage. Among the women with a history of bariatric surgery, the mean pre-surgery BMI was 42.6 kg/m2, the median surgery-to-conception interval was 1.4 years, and the mean BMI loss between surgery and early pregnancy was 13.5 kg/m2 (38 kg). Compared to matched control women, post-surgery women were less likely to have cesarean delivery (18.2% versus 25.0%, risk ratio [RR] 0.70, 95% CI 0.60-0.80), especially emergency cesarean (6.8% versus 15.1%, RR 0.40, 95% CI 0.31-0.51). Post-surgery women also had lower risks of instrumental delivery (5.0% versus 6.5%, RR 0.73, 95% CI 0.53-0.98), induction of labor (23.4% versus 34.0%, RR 0.68, 95% CI 0.59-0.78), post-term pregnancy (4.2% versus 10.3%, RR 0.40, 95% CI 0.30-0.53), obstetric anal sphincter injury (1.5% versus 2.9%, RR 0.46, 95% CI 0.25-0.81), and postpartum hemorrhage (4.6% versus 8.0%, RR 0.58, 95% CI 0.44-0.76). Since this study was not randomized, a limitation is the possibility of selection bias, despite our efforts using careful matching.

CONCLUSIONS

Bariatric-surgery-induced weight loss was associated with lower risks for adverse delivery outcomes in term births.

Diabetes in pregnancy: a new decade of challenges ahead

Every 10 years, the Diabetic Pregnancy Study Group, a study group of the EASD, conducts an audit meeting to review the achievements of the preceding decade and to set the directions for research and clinical practice improvements for the next decade. The most recent meeting focused on the following areas: improving pregnancy outcomes for women with pregestational type 1 diabetes and type 2 diabetes; the influence of obesity and gestational diabetes on pregnancy outcomes; the determinants and assessment of fetal growth and development; and public health issues, including consideration of transgenerational consequences and economic burden. The audit meeting also considered the likely impact of 'omics' on research within the field and the potential of these technologies to enable precision-medicine approaches to management. Through sharing of the findings and ideas of audit meeting participants, the DPSG hopes to promote networking, research and advances in clinical care, to improve outcomes for all women and their offspring affected by diabetes and obesity in pregnancy.

Increased blood levels of persistent organic pollutants (POP) in obese individuals after weight loss-A review

Lipophilic persistent organic pollutants (POP) are stored in adipose tissue. Following rapid weight loss such as when induced by bariatric surgery, an increased release of potential harmful lipophilic compounds into the blood circulation may occur. Weight reduction is recommended for overweight and obese individuals in order to decrease risk of weight-related health problems. However, in cases of significant weight reduction POP become mobilized chemicals and consequently may adversely affect health, including endocrine disruption. The objective of the present investigation was to estimate quantitatively the level of mobilization of POP following weight loss over time. According to literature search criteria, 17 studies were identified with 2061 participants. Data from 5 of the studies with 270 participants were used to assess the change in blood levels of POP in percent per kilogram weight loss. Weight loss in the included studies varied from 4.4 to 64.8 kg. In all studies, the majority of POP concentrations in blood were found to rise following weight reduction. Blood concentrations following weight reduction were elevated by 2-4% per kilogram weight loss for most POP examined. The increased POP levels were still elevated 12 mo after intervention. Most research in this field, including animal studies, is carried out on a single compound or group of selected compounds, not taking the "cocktail effect" into consideration. This does not reflect the true range of POP to which humans are actually exposed. Few chronic investigations have been published and, in particular, few studies were available that compared the increase in POP concentrations with clinical consequences as individuals lost weight. These limitations call for caution in interpreting results. The benefits of losing weight still far outweigh the potential adverse health risks. However, further studies are recommended to determine the clinical significance of increased blood levels of POPs following rapid and excessive weight loss, particularly for women attending weight reduction treatment before pregnancy.