Obstetrical and neonatal outcomes of pregnancies following gastric bypass surgery: a retrospective cohort study in a French referral centre

Gestational Weight Gain Following Metabolic Bariatric Surgery: A Scoping Review

Metabolic bariatric surgery remains the most effective and durable treatment for severe obesity. Women of reproductive age represent the largest demographic group undergoing these procedures. Metabolic bariatric surgery can have both beneficial and adverse effects on pregnancy outcomes. One of the most common adverse effects is fetal growth restriction. To mitigate these adverse effects, it is crucial to explore lifestyle modifications aimed at promoting a healthy pregnancy. Modifiable factors during pregnancy after metabolic bariatric surgery include the amount of gestational weight gain. The aim of this comprehensive review is to provide an overview of what is known about gestational weight gain in pregnancy after bariatric metabolic surgery. This review is focused on the two most performed procedures: sleeve gastrectomy and Roux-en-Y gastric bypass.

Pregnancy After Bariatric Surgery-Experience from a Tertiary Center

INTRODUCTION

It is estimated that most people undergoing bariatric surgery are women of reproductive age; nonetheless, its effects on pregnancy outcomes are not yet fully understood.

METHODS

Retrospective observational study, conducted in a tertiary center in Portugal, included participants in two groups: (1) pregnant women with a history of bariatric surgery (n = 89) and (2) pregnant women with a BMI ≥ 35 kg/m2, without previous bariatric surgery (n = 176). Data was collected from the medical files. Multivariate analysis was conducted to adjust for confounders.

RESULTS

Pregnancy after bariatric surgery was associated with lower risk of gestational diabetes (15.7% vs. 30.1%, p = 0.002) and cesarean delivery (20.7% vs. 33.5%, p = 0.007), and a higher gestational weight gain (10.58 ± 9.95 vs. 7.33 ± 6.00 kg, p < 0.001). Participants in the bariatric surgery who experienced a gestational weight gain ≤ 10.0 kg had a higher risk of preterm delivery (16.7% vs. 2.5%, p = 0.031). No significant differences were found regarding hypertensive diseases of pregnancy between groups (4.5% vs 11.4%, p = 0.147). Pregnancy after bariatric surgery was associated with lower neonate weight percentile (34.24 ± 21.09 vs. 48.77 ± 27.94, p < 0.001), higher risk of fetal growth restriction (5.6% vs. 0.6%, p = 0.018), and lower risk of fetal macrosomia (0.0% vs. 7.5%, p = 0.005). There were no significant differences in the risk of SGA (12.5% vs. 7.0%, p = 0.127) or LGA neonates (2.3% vs. 6.4%, p = 0.069).

CONCLUSION

Pregnancy after bariatric surgery is associated with both risks and benefits, which should be considered by healthcare providers. Pregnancy after bariatric surgery requires individualized care, to ensure adequate gestational weight and avoid micronutrient deficiencies.

Midterm Outcome of Early Pregnancy Versus Late Pregnancy After Laparoscopic Sleeve Gastrectomy

BACKGROUND

Controversy regarding the timing of pregnancy and its implications is present in the literature.

OBJECTIVE

To evaluate the midterm outcome of weight loss in women who have undergone laparoscopic sleeve gastrectomy (LSG) followed by pregnancy at two different times.

METHODS

We retrospectively reviewed 53 women who matched the inclusion criteria and included them in the analysis. Demographics and anthropometric measurements were collected. Women who conceived within 12 months of LSG were labeled as early group (EG), and who conceived after 12 months were noted as late group (LG).

RESULTS

There were no differences between the groups regarding obesity-associated disease and number of pregnancies before. EG had higher weight (P = 0.0001) and body mass index (BMI) (P = 0.002) at LSG. The mean interval time for EG was 6.7 ± 3.2 months, and LG was 20 ± 5.2 months. Gestational weight gain (GWG) was lower in the EG (P = 0.001). There were no differences in the number of small for gestational age (SGA) births or gestational weight. In the first 2 years after LSG, LG had a higher percentage of total weight loss (%TWL) and percentage of body mass index loss (%EBMIL) (P < 0.0001). After 5 years of follow-up, %TWL (P = 0.4) and %EBMIL (P = 0.1) were not statistically significant between both groups.

CONCLUSION

Conception within 12 months from LSG might hinder the weight loss process in the short term but have no significant effect over 5 years of follow-up.

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.

Pregnancy Weight Gain After Gastric Bypass or Sleeve Gastrectomy

Importance

Pregnancy weight gain may affect the association of bariatric surgery with postsurgery pregnancy outcomes. However, the association of pregnancy weight gain with bariatric surgery is unclear.

Objective

To compare pregnancy weight gain among women with a history of bariatric surgery vs those without and to investigate whether pregnancy weight gain differs by surgical procedure, surgery-to-conception interval, and/or surgery-to-conception weight loss.

Design, Setting, and Participants

This nationwide, population-based matched cohort study was conducted in Sweden from 2014 to 2021. Singleton pregnancies with a history of bariatric surgery were propensity score matched (1:1) to pregnancies without such a history according to early-pregnancy body mass index (BMI), prepregnancy diabetes, prepregnancy hypertension, maternal age, smoking status, education level, height, country of birth, and delivery year. In addition, post-gastric bypass pregnancies were matched to post-sleeve gastrectomy pregnancies using the same matching strategy. Data analysis was performed from November 2022 to May 2023.

Exposure

History of bariatric surgery.

Main Outcomes and Measures

Pregnancy weight gain was standardized by gestational age into early-pregnancy BMI-specific z scores.

Results

This study included 12 776 pregnancies, of which 6388 had a history of bariatric surgery and 6388 were matched controls. The mean (SD) age was 31.6 (4.9) years for the surgery group and 31.4 (5.2) for the matched controls, with an early-pregnancy mean (SD) BMI of 29.4 (5.2) in both groups. Across all early-pregnancy BMI strata, women with a history of bariatric surgery had lower pregnancy weight gain than matched controls. The differences in pregnancy weight gain z score values between the 2 groups were -0.33 (95% CI, -0.43 to -0.23) for normal weight, -0.33 (95% CI, -0.40 to -0.27) for overweight, -0.21 (95% CI, -0.29 to -0.13) for obese class I, -0.16 (95% CI, -0.29 to -0.03) for obese class II, and -0.08 (95% CI, -0.28 to 0.13) for obese class III. Pregnancy weight gain did not differ by surgical procedure. A shorter surgery-to-conception interval (particularly within 1 year) or lower surgery-to-conception weight loss was associated with lower pregnancy weight gain.

Conclusions and Relevance

In this nationwide matched cohort study, women with a history of bariatric surgery had lower pregnancy weight gain than matched controls with similar early-pregnancy characteristics. Pregnancy weight gain was lower in those with a shorter surgery-to-conception interval or lower surgery-to-conception weight loss, but did not differ by surgical procedure.

Adverse perinatal outcomes after Roux-en-Y Gastric Bypass vs. Sleeve Gastrectomy: a systematic review

BACKGROUND

Pregnancies occurring after bariatric surgery are associated with various perinatal complications. However, there may be differences in the type of perinatal complications occurring after different methods of bariatric surgery. The aim of the current study was to compare adverse perinatal outcomes in pregnant women following Roux-en-Y Gastric Bypass (RYGB) vs. Sleeve Gastrectomy (SG).

METHODS

A systematic database search was performed in PubMed, Embase, Scopus and CINAHL. Observational studies comparing perinatal outcomes post-bariatric (RYGB and SG) surgery to pregnancies without prior surgery were selected. Outcomes of interest were: maternal body mass index (BMI) at the time of conception, mode of delivery, time from surgery to conception, birth weight, gestational age and intrauterine fetal death. Article selection, risk of bias assessment and data extraction, were performed by two authors. The study protocol was published in its revised form in PROSPERO, registration number: CRD42021234480.

RESULTS

A total of 3201 records were extracted. After duplicates were removed, 3143 records were screened for inclusion. Six studies fitted the selection criteria, of which four studies were RYGB and two SG (1100 post-RYGB vs. 209 post-SG). For the included studies, higher incidence of both SGA (22.9%, 11.9%, 14.2%) and LGA (4.2%, 4.8%, 1.7%) in SG compared to Roux-en-Y (SGA: 8.8%, 7.7%, 11.5%, 8.3% and LGA: 3.4%, 0.7%) were observed. SG had a shorter surgery to conception interval as compared to RYGB. Risk of bias assessment was moderate to serious for the studies included in the review, with bias in selection of participants being the major reason.

CONCLUSION

Our systematic review demonstrated no major differences in BMI, mode of delivery, birthweight, gestational age, or rates of intrauterine death between women having undergone RYGB vs. SG. The rate of SGA and LGA births were higher in the SG group, but this group also had a shorter surgery to conception interval. Future studies are indicated to counsel women of reproductive age on the most appropriate type of bariatric surgery that is associated with the best perinatal outcomes.

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.

Trimester-specific gestational weight gain in women with and without previous bariatric surgeries

OBJECTIVES

The study aimed 1) to compare trimester-specific and total gestational weight gain (GWG) between mothers who had undergone biliopancreatic diversion with duodenal switch (BPD) and two control groups of unoperated women and 2) to examine the associations between GWG, intrauterine fetal growth and neonatal birthweight.

METHODS

This retrospective study included data collected in medical records of newborns and mothers from 3 groups: the first control group (PP) included mothers (n = 158) with a pre-pregnancy BMI similar to that of the surgical group (n = 63) and the second one (PS) included mothers (n = 85) with a pre-pregnancy BMI corresponding to that of the surgical group prior to BPD or a BMI > 40 kg/m². Trimester-specific GWG was obtained using linear interpolation and compared to the recommendations.

RESULTS

Women exposed to BPD have an increased prevalence of insufficient weight gain in the second and third trimesters as well as for the whole pregnancy in comparison with women in the PP group. The weekly GWG rate in the third trimester was significantly lower in women exposed to BPD, compared to both control groups. Although the newborns of women with previous BPD were significantly smaller during pregnancy and at birth, no association was found with GWG.

CONCLUSION

Women exposed to BPD are at substantial risk of insufficient GWG, however, mechanisms and long-term impacts require further investigation.

Preconceptional maternal weight loss and hypertensive disorders in pregnancy: a systematic review and meta-analysis

BACKGROUND

Hypertensive disorders of pregnancy (HDP), including pregnancy-induced hypertension (PIH), Preeclampsia (PE), Hemolysis Elevated Liver enzymes and Low Platelets (HELLP) and chronic hypertension, are leading causes of maternal and perinatal morbidity and mortality. Although the pathophysiology of HDP is complex, preconceptional weight reduction in obese women might reduce these complications. We conducted a systematic review and meta-analysis to investigate the effectiveness of preconceptional weight loss by lifestyle intervention or bariatric surgery in overweight and obese women and the reduction of the risk of HDP.

METHODS AND RESULTS

Databases are searched until September 2019 resulting in 2547 articles: 110 full-text analysis and 29 detailed analysis. Reduced risks were shown for HDP in seven articles (n = 4381) of weight loss after lifestyle intervention or bariatric surgery (OR range 0.10-0.64), for PIH in four articles (n = 46,976) (OR range 0.14-0.79), and for PE in seven articles (n = 169,734) (OR range 0.14-0.84). The stratified analysis of weight loss after lifestyle intervention and bariatric surgery shows comparable results. The meta-analysis of 20 studies of the effectiveness of lifestyle intervention and bariatric surgery revealed reduced risks of HDP (OR 0.45 (95% CI 0.32-0.63)), PIH (OR 0.61 (95%CI 0.44-0.85)) and PE (OR 0.67 (95%CI 0.51-0.88)).

CONCLUSIONS

Preconceptional weight loss after lifestyle intervention or bariatric surgery is effective in reducing risks of HDP, PIH and PE, and emphasizes the need to optimize weight in overweight and obese women with a child wish. More research is recommended to investigate short-term and long-term beneficial and harmful side-effects of these interventions on maternal and offspring health.

Risk of pre-eclampsia after gastric bypass: a matched cohort study

OBJECTIVE

To investigate whether gastric bypass before pregnancy is associated with reduced risk of pre-eclampsia.

DESIGN

Nationwide matched cohort study.

SETTING

Swedish national health care.

POPULATION

A total of 843 667 singleton pregnancies without pre-pregnancy hypertension were identified in the Swedish Medical Birth Register between 2007 and 2014, of which 2930 had a history of gastric bypass and a pre-surgery weight available from the Scandinavian Obesity Surgery Registry. Two matched control groups (pre-surgery and early-pregnancy body mass index [BMI]) were propensity score matched separately for nulliparous and parous births, to post-gastric bypass pregnancies (n_{pre-surgery-BMI}  = 2634:2634/n_{early-pregnancy-BMI}  = 2766:2766) on pre-surgery/early-pregnancy BMI, diabetes status (pre-surgery/pre-conception), maternal age, early-pregnancy smoking status, educational level, height, country of birth, delivery year and history of pre-eclampsia.

MAIN OUTCOME MEASURES

Pre-eclampsia categorised into any, preterm onset (<37⁺⁰  weeks) and term onset (≥37⁺⁰  weeks).

RESULTS

In post-gastric bypass pregnancies, mean pre-surgery BMI was 42.9 kg/m² and mean BMI loss between surgery and early pregnancy was 14.0 kg/m² (39 kg). Post-gastric bypass pregnancies had lower risk of pre-eclampsia compared with pre-surgery BMI-matched controls (1.7 versus 9.7 per 100 pregnancies; hazard ratio [HR] 0.21, 95% CI 0.15-0.28) and early-pregnancy BMI-matched controls (1.9 versus 5.0 per 100 pregnancies; HR 0.44, 95% CI 0.33-0.60). Although relative risks for pre-eclampsia for post-gastric bypass pregnancies versus pre-surgery matched controls was similar, absolute risk differences (RD) were significantly greater for nulliparous women (RD -13.6 per 100 pregnancies, 95% CI -16.1 to -11.2) versus parous women (RD -4.4 per 100 pregnancies, 95% CI -5.7 to -3.1).

CONCLUSION

We found that gastric bypass was associated with lower risk of pre-eclampsia, with the largest absolute risk reduction among nulliparous women.

TWEETABLE ABSTRACT

In this large study including two comparison groups matched for pre-surgery or early-pregnancy BMI, gastric bypass was associated with lower risk of pre-eclampsia.

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.

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.

Pregnancy outcomes following different types of bariatric surgery: A national cohort study

OBJECTIVE

To assess the impact of type of bariatric surgery on pregnancy outcomes.

STUDY DESIGN

This is a national prospective observational study using the UK Obstetric Surveillance System (UKOSS). Data collection was undertaken in 200 consultant-led NHS maternity units between November 2011 and October 2012 (gastric banding), and April 2014 and March 2016 (gastric bypass and sleeve gastrectomy). Participants were pregnant women following gastric banding (n = 127), gastric bypass (n = 134) and sleeve gastrectomy (n = 29). Maternal and perinatal outcomes were compared using generalised linear and linear mixed models. Maternal outcomes included gestational weight gain, pre-eclampsia, gestational diabetes, anaemia, surgical complications. Perinatal outcomes included birthweight, small/large for gestational age (SGA/LGA), preterm birth, stillbirth.

RESULTS

Maternal: Women pregnant after gastric banding and sleeve gastrectomy had a lower risk of anaemia compared with gastric bypass (banding (16 %) vs bypass (39 %): p = 0.002, sleeve (21 %) vs bypass: p = 0.04). Gestational diabetes risk was lower after gastric banding compared with gastric bypass (7 % vs 16 %, p = 0.03) despite women with banding having significantly greater weight at booking as well as gestational weight gain. Women pregnant after gastric banding and sleeve gastrectomy had a lower risk of surgical complications than after gastric bypass (banding (0.9 %) vs bypass (11.4 %): p = 0.03, sleeve (0.0 %) vs bypass: p = 0.06). Perinatal: Infants born to mothers after gastric banding had a higher birthweight than those born to mothers after gastric bypass (mean difference = 260 g (125-395), p < 0.001). Infants were more likely to be LGA if their mothers had gastric banding compared with gastric bypass or sleeve gastrectomy (banding (21 %) vs bypass (5 %): p = 0.006; banding vs sleeve (3 %): p = 0.03). Risk of preterm birth was higher in women with gastric banding compared with gastric bypass (13 % vs 8 %, p = 0.04).

CONCLUSIONS

Women planning bariatric surgery should be counselled regarding the differing impacts of different types of procedure on any future pregnancy. Pre-existing gastric bypass is associated with higher rates of potentially serious surgical complications during pregnancy.

A Prospective Study of Association of Micronutrients Deficiencies during Pregnancy and Neonatal Outcome among Women after Bariatric Surgery

Little is known about the association of micronutrients deficiencies during pregnancy and neonatal outcome among women after Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG). We present a prospective study of 87 consecutive women with a history of RYGB (n = 37) or SG (n = 50) who underwent complete and regular clinical and biological nutritional assessments during pregnancy. Data on maternal characteristics, biological nutritional parameters, antenatal management, and perinatal outcome were collected. The objective was to evaluate serum levels of micronutrients at the second trimester, and to assess the association between micronutrients deficiencies and neonatal outcome. After RYGB, maternal age (34.3 ± 4.9 vs. 31.1 ± 4.6 years; p = 0.003) and pregnancy timing after surgery (64.5 ± 47.0 vs. 38.1 ± 28.1 months; p = 0.002) were significantly higher, and pre-pregnancy BMI was significantly lower (29.8 ± 5.6 vs. 32.9 ± 7.1 kg/m2; p = 0.03). Maternal and neonatal outcomes were similar. Additional supplementations after blood tests were similar in groups. Zinc, selenium, vitamins A1, B1, B6, C, and E levels were not different depending on the type of surgery. Zinc deficiency (7/87) was significantly more frequent after RYGP (18.9% vs. 0%; p = 0.02) and selenium deficiency (15/87) was similar in groups (21.6% after RYGB and 14.0% after SG; p = 0.36). The mean birth weight was significantly lower in selenium deficiency cases (3137 ± 550 vs. 3535 ± 737 g; p = 0.04). Selenium deficiency was negatively correlated with birth weight (r = -0.23; p = 0.03) and with birth weight z-score (r = -0.26; p = 0.01), but not correlated after adjustment for the procedure. The levels of micronutrients surveillance along pregnancy in women with a history of bariatric surgery is necessary to decrease the risk of inadequate fetal growth in the patients.

Gestational weight gain and postpartum weight retention after bariatric surgery: data from a prospective cohort study

BACKGROUND

It is unknown whether international guidelines on gestational weight gain can be used in pregnancies after bariatric surgery.

OBJECTIVES

To investigate gestational weight gain, intrauterine growth, and postpartum weight retention in postbariatric women.

SETTING

8 Belgian hospitals.

METHODS

Prospective data from 127 postbariatric pregnancies from September 2014 through October 2018. Patients were grouped according to achievement of 2009 Institute of Medicine (IOM) guidelines.

RESULTS

In 127 patients with a mean age of 30.2 years (standard deviation [SD], 4.7), the mean gestational weight gain was 12.5 kg (SD, 6.7). Of these patients, 24% (30 of 127) showed insufficient weight gain, 20% (26 of 127) showed adequate weight gain, and 56% (71 of 127) showed excessive weight gain. Of 127 patients, 27 (21%) had small-for-gestational-age infants. This peaked in the group with insufficient weight gain (47%; 95% confidence interval [CI], 29%-65%; P < .001). The prevalence of large-for-gestational-age infants was comparable between groups, although highest in the group with excessive weight gain (0% in those with insufficient weight gain, 4% in those with adequate weight gain, and 8% in those with excessive weight gain). Preterm births were recorded more in patients with insufficient weight gain (23%; 95% CI, 8%-38%; P = .048). The mean amounts of postpartum weight retained were 4.0 kg (SD, 7.4) at 6 weeks and 3.0 kg (SD, 9.1) at 6 months. Weight retention at 6 weeks (7.1 kg; 95% CI, 5.5-8.7; P < .001) and 6 months (8.3 kg; 95% CI, 4.5-12.2; P < .001) was highest in women gaining excessive weight.

CONCLUSION

Achievement of IOM guidelines is low in postbariatric pregnancies. Insufficient weight gain increases the risk for small-for-gestational-age babies. Excessive weight gain increases weight retention after delivery and could precipitate weight regain. After bariatric surgery, women should be encouraged to achieve IOM recommendations.

Curbing Obesity from One Generation to Another: the Effects of Bariatric Surgery on the In Utero Environment and Beyond

Approximately 250,000 individuals seek bariatric surgery each year in the USA for the long-term resolution of obesity-related comorbidities. Greater than 80% of these individuals are women and approximately half are of child-bearing age. Although there are many positive metabolic benefits that are realized through surgical weight loss for both men and women, the various long-term hormonal, molecular, nutrient, and epigenetic changes following bariatric surgery have not been evaluated for the surgical recipient or in the context of pregnancy and the offspring. Pregnancy may be a vulnerable period of time for the bariatric surgery recipient, and thoughtful consideration of pregnancy management should be taken by health care providers and recipients alike. The purpose of this review is to explore potential etiologies of some of the gestation-specific outcomes for the mother and offspring.

Pregnancy after bariatric surgery: Consensus recommendations for periconception, antenatal and postnatal care

The objective of the study is to provide evidence-based guidance on nutritional management and optimal care for pregnancy after bariatric surgery. A consensus meeting of international and multidisciplinary experts was held to identify relevant research questions in relation to pregnancy after bariatric surgery. A systematic search of available literature was performed, and the ADAPTE protocol for guideline development followed. All available evidence was graded and further discussed during group meetings to formulate recommendations. Where evidence of sufficient quality was lacking, the group made consensus recommendations based on expert clinical experience. The main outcome measures are timing of pregnancy, contraceptive choice, nutritional advice and supplementation, clinical follow-up of pregnancy, and breastfeeding. We provide recommendations for periconception, antenatal, and postnatal care for women following surgery. These recommendations are summarized in a table and print-friendly format. Women of reproductive age with a history of bariatric surgery should receive specialized care regarding their reproductive health. Many recommendations are not supported by high-quality evidence and warrant further research. These areas are highlighted in the paper.

Management of surgical complications of previous bariatric surgery in pregnant women. A systematic review from the BARIA-MAT Study Group

Considering the large and increasing population of women of childbearing age with history of bariatric surgery, surgical complications of bariatric surgery during pregnancy may become more frequent in the future. The aim of this study was to analyze the clinical presentation, diagnostic procedures, and treatment of surgical complications of bariatric surgery during pregnancies. A systematic literature search was performed in accordance with the PRISMA (preferred reporting items for systematic review and meta-analysis) guidelines to identify all studies published up to and including December 2018 that included women with previous bariatric surgery undergoing emergency surgery during pregnancy. Sixty-eight studies were selected, including 120 women with previous bariatric surgery undergoing emergency surgery during pregnancy. Fifty cases were reported as case reports and 70 in case series. Included patients had previous history of Roux-en-Y gastric bypass (n = 99), laparoscopic adjustable gastric banding (n = 17), Scopinaro procedure (n = 2), vertical banded gastroplasty (n = 1), or one-anastomosis gastric bypass (n = 1). Final diagnosis in 50 case reports was internal hernia in 26 cases, bowel intussusception in 10, intestinal obstruction in 2, laparoscopic adjustable gastric banding slippage in 3, bowel volvulus in 3, gastric or jejunal perforation in 2, and other complications in 4 cases. Maternal and fetal death occurred in 3 (2.5%) and 9 cases (7.5%), respectively. In the case series, the majority of women were operated for internal hernia and laparoscopic adjustable gastric banding slippage. Surgical complications of previous bariatric surgery during pregnancy have potentially severe outcomes. Availability of multidisciplinary expertise, including bariatric/digestive surgeons, and education of healthcare providers and women on clinical signs that require urgent surgical examination are recommended in this setting. Prompt diagnosis is fundamental and based on clinical and laboratory findings and on radiologic examinations if needed, including computed tomography scan or magnetic resonance if available. Rapid surgical exploration is mandatory in case of high clinical and/or radiologic suspicion.

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 and Perinatal Outcomes After Laparoscopic Sleeve Gastrectomy

OBJECTIVE

To examine associations of laparoscopic sleeve gastrectomy with maternal and perinatal outcomes.

METHODS

We conducted a retrospective case-control study of deliveries that occurred from 2006 to 2016 at two university hospitals. The study group comprised all women who had undergone laparoscopic sleeve gastrectomy and who delivered during the study period. If a woman had more than one pregnancy during the study period, data from only her first pregnancy were used. A control group was established by matching preoperative body mass index (BMI), age, parity, delivery history, and delivery year.

RESULTS

Data from 238 women were analyzed, 119 post-laparoscopic sleeve gastrectomy and 119 matched control parturients. Among the post-laparoscopic sleeve gastrectomy patients, the median preoperative BMI was 41.7 (interquartile range 39.9-44.4) and the median postoperative BMI was 28.9 (26.6-32.0). Compared with the control group, the study group had lower rates of gestational diabetes mellitus (3.4% vs 17.6%, P=.001), large-for-gestational-age neonates (1.7% vs 19.3%, P=.001), and birth weight greater than 4,000 g (0.8% vs 7.6%, P=.02) but higher proportions of small-for-gestational-age (SGA) neonates (14.3% vs 4.2%, P=.01) and low-birth-weight neonates (12.6% vs 4.2%, P=.03). Rates of gestational hypertensive disorders and prematurity were comparable between the groups. For the study group, hemoglobin levels were lower in early pregnancy (median 12.6 vs 13.2 g/dL, P=.001) and after delivery (10.5 vs 10.8 g/dL, P=.002), and a higher proportion of patients were treated with intravenous iron supplementation during pregnancy (14.3% vs 0.8%, P=.001). Cesarean delivery rates during labor were lower in the study group (10.1% vs 20.2%, P=.04).

CONCLUSION

Laparoscopic sleeve gastrectomy was associated with reduced rates of gestational diabetes mellitus, excessive fetal growth, and cesarean delivery and an increased rate of SGA and low-birth-weight neonates.

Effects of Bariatric Surgery on Maternal and Infant Outcomes of Pregnancy-An Evidence Analysis Center Systematic Review

BACKGROUND

While obesity presents specific acute and long-term risks to the pregnant woman and her offspring, the effects of bariatric surgery on pregnancy outcomes are undetermined.

OBJECTIVE

A systematic review was performed according to the Academy of Nutrition and Dietetics Evidence Analysis Library process to determine the effects of bariatric surgery on both maternal and infant health outcomes of pregnancy.

DESIGN

A comprehensive literature search of PubMed was conducted to identify studies published from years 2000 to 2015 that examined the health effects of pregnancy after bariatric surgery. Experimental studies and observational studies with a control group were included.

MAIN OUTCOME MEASURES

Outcomes of interest were gestational weight gain, maternal complications (ie, gestational diabetes, pre-eclampsia, eclampsia, hypertension, and postpartum hemorrhage), miscarriage and/or stillbirth, cesarean section, birth weight in grams, birth weight in categories (ie, macrosomia, low birth weight, small for gestational age, and large for gestational age), gestational age and preterm birth, infant illness and complications (ie, perinatal death, admission to neonatal intensive care unit, neonatal illness, and congenital malformation rates), and Apgar scores.

RESULTS

Thirteen of 246 studies were included. Compared to body mass index-matched controls without surgery, bariatric surgery before pregnancy reduced infant birth weight in grams, with no effect on total maternal gestational weight gain or Apgar scores. Surgery did not increase risk of adverse outcomes, such as miscarriage and/or stillbirth, preterm birth, or infant complications. Effects of surgery on maternal complications, infant birth weight categories, and surgical delivery rates were inconsistent.

CONCLUSIONS

Bariatric surgery is a successful treatment of maternal obesity, but certain surgery-specific risks may exist. More data are needed to determine clinical guidelines. The long-term effects of surgery on pregnancy outcomes are unknown.

Preconception management of women with obesity: A systematic review

The prevalence of women of child-bearing age with obesity continues to rise at an alarming rate. This has significant implications for both the short-term and long-term health of mother and offspring. Given the paucity of evidence-based literature in this field, the preconception management of women with obesity is highly variable both between institutions and around the world. This systematic review aims to evaluate studies that inform us about the role of preconception weight loss in the fertility and pregnancy outcomes of women with obesity. Current therapeutic interventions are discussed, with a specific focus on the suitability of weight loss interventions for women with obesity planning pregnancy. There are significant knowledge gaps in the current literature; these are discussed and areas for future research are explored.

Vitamin A and β-carotene in pregnant and breastfeeding post-bariatric women in an urban population

Background As breastfeeding awareness and social acceptance are increased, maternal nutritional deficiency requires more investigation. Methods A prospective cohort study was conducted to determine if vitamin A deficiency is more common in pregnant, lactating post-bariatric surgery women in an inner city population. Antepartum, women after bariatric surgery and controls with no history of malabsorption were recruited. Third trimester, postpartum maternal blood and cord blood were collected as well as three breast milk samples: colostrum, transitional and mature milk. A nutritional survey of diet was completed. Each serum sample was analyzed for total retinol and β-carotene; breast milk samples were analyzed for retinol and retinyl esters, total retinol and β-carotene. Results Fifty-three women after bariatric surgery and 66 controls were recruited. Postpartum serum retinol was significantly higher in women after bariatric surgery in the univariate analysis (P<0.0001) and confirmed in the multiple linear mixed model (P=0.0001). Breast milk colostrum retinol and transitional milk total retinol were significantly greater in the bariatric surgery group in the univariate analysis (P=0.03 and P=0.02, respectively), but not after adjusting for confounders. Serum β-carotene in the third trimester and postpartum were lower (P<0.0001 and P=0.003, respectively) in the bariatric surgery group but not after adjusting for confounders. Vitamin A deficiency was high in both groups in serum and breast milk samples. Conclusion Nutritional deficiencies in breastfeeding women after bariatric surgeries may in fact be less common than in control women in an inner city.

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.

Maternal and neonatal outcomes after bariatric surgery; a systematic review and meta-analysis: do the benefits outweigh the risks?

OBJECTIVE DATA

Obesity during pregnancy is associated with a number of adverse obstetric outcomes that include gestational diabetes mellitus, macrosomia, and preeclampsia. Increasing evidence shows that bariatric surgery may decrease the risk of these outcomes. Our aim was to evaluate the benefits and risks of bariatric surgery in obese women according to obstetric outcomes.

STUDY

We performed a systematic literature search using MEDLINE, Embase, Cochrane, Web of Science, and PubMed from inception up to December 12, 2016. Studies were included if they evaluated patients who underwent bariatric surgery, reported subsequent pregnancy outcomes, and compared these outcomes with a control group.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two reviewers extracted study outcomes independently, and risk of bias was assessed with the use of the Newcastle-Ottawa Quality Assessment Scale. Pooled odds ratios for each outcome were estimated with the Dersimonian and Laird random effects model.

RESULTS

After a review of 2616 abstracts, 20 cohort studies and approximately 2.8 million subjects (8364 of whom had bariatric surgery) were included in the metaanalysis. In our primary analysis, patients who underwent bariatric surgery showed reduced rates of gestational diabetes mellitus (odds ratio, 0.20; 95% confidence interval, 0.11-0.37, number needed to benefit, 5), large-for-gestational-age infants (odds ratio, 0.31; 95% confidence interval, 0.17-0.59; number needed to benefit, 6), gestational hypertension (odds ratio, 0.38; 95% confidence interval, 0.19-0.76; number needed to benefit, 11), all hypertensive disorders (odds ratio, 0.38; 95% confidence interval, 0.27-0.53; number needed to benefit, 8), postpartum hemorrhage (odds ratio, 0.32; 95% confidence interval, 0.08-1.37; number needed to benefit, 21), and caesarean delivery rates (odds ratio, 0.50; 95% confidence interval, 0.38-0.67; number needed to benefit, 9); however, group of patients showed an increase in small-for-gestational-age infants (odds ratio, 2.16; 95% confidence interval, 1.34-3.48; number needed to harm, 21), intrauterine growth restriction (odds ratio, 2.16; 95% confidence interval, 1.34-3.48; number needed to harm, 66), and preterm deliveries (odds ratio, 1.35; 95% confidence interval, 1.02-1.79; number needed to harm, 35) when compared with control subjects who were matched for presurgery body mass index. There were no differences in rates of preeclampsia, neonatal intensive care unit admissions, stillbirths, malformations, and neonatal death. Malabsorptive surgeries resulted in a greater increase in small-for-gestational-age infants (P=.0466) and a greater decrease in large-for-gestational-age infants (P=<.0001) compared with restrictive surgeries. There were no differences in outcomes when we used administrative databases vs clinical charts.

CONCLUSION

Although bariatric surgery is associated with a reduction in the risk of several adverse obstetric outcomes, there is a potential for an increased risk of other important outcomes that should be considered when bariatric surgery is discussed with reproductive-age women.

Health consequences for mother and baby of substantial pre-conception weight loss in obese women: study protocol for a randomized controlled trial

BACKGROUND

Current guidelines for the management of obesity in women planning pregnancy suggest lifestyle modification before conception. However, there is little evidence that lifestyle modification alters pregnancy outcomes. Bariatric surgery results in significant weight loss. This appears to reduce the risk of adverse pregnancy outcomes for the mother but may increase the risk of adverse outcomes for the infant. In order to reduce the risks of obesity-related adverse pregnancy outcomes for both mother and offspring, alternative approaches to the management of obesity in women planning pregnancy are needed.

METHODS/DESIGN

This study, a two-arm, parallel group, randomized control trial, will be conducted at the Metabolic Disorders Centre, University of Melbourne. This trial will recruit 164 women aged 18-38 years with a body mass index of 30-55 kg/m² who plan to conceive in the next 6-12 months. Women will be randomized to one of two 12-week interventions (Group A and Group B). Group A will aim for modest weight loss (MWL; ≤ 3% body weight) using a hypocaloric diet. Group B will aim for substantial weight loss (SWL; 10-15% body weight) using a modified very low energy diet (VLED) program. All participants will be asked to comply with National Health and Medical Research Council (NHMRC) guidelines for exercise and will be provided with standard pre-pregnancy advice according to Royal Australian and New Zealand College of Obstetrics and Gynaecology guidelines. All participants will then be observed for the subsequent 12 months. If pregnancy occurs within the 12-month follow-up period, data on weight and metabolic status of the mother, and pregnancy outcomes of mother and offspring will be recorded. The primary outcome is maternal fasting plasma glucose at 26-28 weeks' gestation, given that this is known to correlate with pregnancy outcomes. Time to conception, live birth rate, gestational weight gain, and a composite of adverse pregnancy outcomes for mother and baby will comprise the secondary outcomes.

DISCUSSION

There is increasing emphasis on obese women losing weight before conception. To date, no randomized controlled trial has demonstrated an effective means of weight loss that results in improved pregnancy outcomes for both mother and baby. This study intends to determine if substantial pre-conception weight loss, achieved using a VLED, improves pregnancy outcomes for mother and baby when compared with standard care. This research will potentially change clinical care of an obese woman planning pregnancy.

TRIAL REGISTRATION

ANZCTR, 12,614,001,160,628 . Registered on 5 November 2014.

A Time Interval of More Than 18 Months Between a Pregnancy and a Roux-en-Y Gastric Bypass Increases the Risk of Iron Deficiency and Anaemia in Pregnancy

OBJECTIVE

The aim of the study is to explore the impact of time between Roux-en-Y gastric bypass (RYGB) and pregnancy on obstetrical outcome and nutritional derangements.

METHODS

In a retrospective cross-sectional study of pregnant women admitted for antenatal care at two tertiary hospitals, we examined 153 women with RYGB and a singleton pregnancy of at least 24 weeks. The women were stratified according to a pregnancy <18 months (40 women) or ≥18 months (113 women) after RYGB. Main outcome measures were nutritional parameters and glycated haemoglobin 1Ac (HbA1c) in second and third trimester of pregnancy, gestational hypertension, length of pregnancy, mode of delivery and foetal birth weight.

RESULTS

The two groups were comparable regarding age, parity and prepregnancy body mass index. The frequency of iron deficiency anaemia (ferritin <12 μg/L and haemoglobin <6.5 mmol/L/10.5 g/dL) was significantly higher in the late group, 29 vs. 8 % in the early group, p = 0.010. No differences were found for vitamin B12, vitamin D and zinc. Median HbA1c was significantly higher in the late group than in the early group (33 vs. 31 mmol/mol, p = 0.027). There were no significant differences in the risk of adverse pregnancy outcome or birth weight between the two groups.

CONCLUSION

A long surgery-to-pregnancy time interval after a RYGB increases the risk of iron deficiency anaemia but not of other nutritional deficits. Time interval does not seem to have an adverse effect on the obstetrical outcome, including intrauterine growth restriction. Specific attention is needed on iron deficit with increasing surgery-to-pregnancy time interval.

Bariatric Surgery: A Perspective for Primary Care

IN BRIEF Bariatric surgery is the most efficacious treatment for obesity, type 2 diabetes, and other obesity-related comorbidities. In this article, the authors review the current indications for bariatric surgery and discuss the most commonly performed procedures. They analyze medical outcomes of bariatric procedures by reviewing key prospective trials and discuss changes in physiology after these procedures. They conclude by discussing long-term management of bariatric patients by reviewing current guidelines for nutritional support and listing common complications related to these procedures.

What Bariatric Surgery Can Teach Us About Endoluminal Treatment of Obesity and Metabolic Disorders

Bariatric surgical procedures, including gastric bypass, vertical sleeve gastrectomy, and biliopancreatic diversion, are the most effective and durable treatments for obesity. In addition, These operations induce metabolic changes that provide weight-independent improvement in type 2 diabetes, fatty liver disease and other metabolic disorders. Initially thought to work by mechanical restriction of food intake or malabsorption of ingested nutrients, these procedures are now known to work through complex changes in neuroendocrine and immune signals emanating from the gut, including peptide hormones, bile acids, vagal nerve activity, and metabolites generated by the gut microbiota, all collaborating to reregulate appetite, food preference, and energy expenditure. Development of less invasive means of achieving these benefits would allow much greater dissemination of effective, gastrointestinal (GI)-targeted therapies for obesity and metabolic disorders. To reproduce the benefits of bariatric surgery, however, these endoscopic procedures and devices will need to mimic the physiological rather than the mechanical effects of these operations.

Pregnancy after bariatric surgery: improving outcomes for mother and child

The significant increase in the prevalence of obesity has led to an increase in the number of obese women who become pregnant. In this setting, in recent years, there has been an exponential rise in the number of bariatric procedures, with approximately half of them performed in women of childbearing age, and a remarkable surge in the number of women who become pregnant after having undergone bariatric surgery (BS). These procedures entail the risk of nutritional deficiencies, and nutrition is a crucial aspect during pregnancy. Therefore, knowledge and awareness of the consequences of these techniques on maternal and fetal outcomes is essential. Current evidence suggests a better overall obstetric outcome after BS, in comparison to morbid obese women managed conservatively, with a reduction in the prevalence of gestational diabetes mellitus, pregnancy-associated hypertensive disorders, macrosomia, and congenital defects. However, the risk of potential maternal nutritional deficiencies and newborns small for gestational age cannot be overlooked. Results concerning the incidence of preterm delivery and the number of C-sections are less consistent. In this paper, we review the updated evidence regarding the impact of BS on pregnancy.

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.

Bariatric Surgery and the Pregnancy Complicated by Gestational Diabetes

Gestational diabetes mellitus (GDM) is an increasingly common obstetrical problem. Due to the global escalation in the prevalence of obesity, as many as 15 % of pregnant women may soon be classified as having GDM. While often not diagnosed until late gestation, GDM is now recognized as a disorder of glucose and lipid metabolism, systemic inflammation, and insulin resistance that begins early in pregnancy. Recent large randomized trials have clarified the risk of maternal and neonatal complications caused by GDM, as well as the potential to ameliorate these risks. There is significant interest in the potential to reduce the risk for developing GDM in obese women through the performance of bariatric surgery (BS) before pregnancy. BS significantly reduces the risk for GDM, preeclampsia, and large neonates. However, it seems that the risk for small neonates and preterm delivery is increased. No significant differences are observed in regard to cesarean section, postpartum hemorrhage, or perinatal mortality. In this article, we address the effects of GDM on the mother and child, and explore the risks and benefits of BS in the obstetrical population.

[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.

Maternal and neonatal outcomes for pregnancies before and after gastric bypass surgery

BACKGROUND

Interaction between maternal obesity, intrauterine environment and adverse clinical outcomes of newborns has been described.

METHODS

Using statewide birth certificate data, this retrospective, matched-control cohort study compared paired birth weights and complications of infants born to women before and after Roux-en-Y gastric bypass surgery (RYGB) and to matched obese non-operated women in several different groups. Women who had given birth to a child before and after RYGB (group 1; n=295 matches) and women with pregnancies after RYGB (group 2; n=764 matches) were matched to non-operated women based on age, body mass index (BMI) prior to both pregnancy and RYGB, mother's race, year of mother/s birth, date of infant births and birth order. In addition, birth weights of 13 143 live births before and/or after RYGB of their mothers (n=5819) were compared (group 3).

RESULTS

Odds ratios (ORs) for having a large-for-gestational-age (LGA) neonate were significantly less after RYGB than for non-surgical mothers: ORs for groups 1 and 2 were 0.19 (0.08-0.38) and 0.33 (0.21-0.51), respectively. In contrast, ORs in all three groups for risk of having a small for gestational age (SGA) neonate were greater for RYGB mothers compared to non-surgical mothers (ORs were 2.16 (1.00-5.04); 2.16 (1.43-3.32); and 2.25 (1.89-2.69), respectively). Neonatal complications were not different for group 1 RYGB and non-surgical women for the first pregnancy following RYGB. Pregnancy-induced hypertension and gestational diabetes were significantly lower for the first pregnancy of mothers following RYGB compared to matched pregnancies of non-surgical mothers.

CONCLUSION

Women who had undergone RYGB not only had lower risk for having an LGA neonate compared to BMI-matched mothers, but also had significantly higher risk for delivering an SGA neonate following RYGB. RYGB women were less likely than non-operated women to have pregnancy-related hypertension and diabetes.

Maternal and neonatal outcomes in women undergoing bariatric surgery: a systematic review and meta-analysis

BACKGROUND

Obese women are at increased risk for many pregnancy complications, and bariatric surgery (BS) before pregnancy has shown to improve some of these.

OBJECTIVES

To review the current literature and quantitatively assess the obstetric and neonatal outcomes in pregnant women who have undergone BS.

SEARCH STRATEGY

MEDLINE, EMBASE and Cochrane databases were searched using relevant keywords to identify studies that reported on pregnancy outcomes after BS.

SELECTION CRITERIA

Pregnancy outcome in firstly, women after BS compared to obese or BMI-matched women with no BS and secondly, women after BS compared to the same or different women before BS. Only observational studies were included.

DATA COLLECTION AND ANALYSIS

Two investigators independently collected data on study characteristics and outcome measures of interest. These were analysed using the random effects model. Heterogeneity was assessed and sensitivity analysis was performed to account for publication bias.

MAIN RESULTS

The entry criteria were fulfilled by 17 non-randomised cohort or case-control studies, including seven with high methodological quality scores. In the BS group, compared to controls, there was a lower incidence of preeclampsia (OR 0.45, 95% CI 0.25-0.80; P=0.007), GDM (OR 0.47, 95% CI 0.40-0.56; P<0.001) and large neonates (OR 0.46, 95% CI 0.34-0.62; P<0.001) and a higher incidence of small neonates (OR 1.93, 95% CI 1.52-2.44; P<0.001), preterm birth (OR 1.31, 95% CI 1.08-1.58; P=0.006), admission for neonatal intensive care (OR 1.33, 95% CI 1.02-1.72; P=0.03) and maternal anaemia (OR 3.41, 95% CI 1.56-7.44, P=0.002).

CONCLUSIONS

BS as a whole improves some pregnancy outcomes. Laparoscopic adjustable gastric banding does not appear to increase the rate of small neonates that was seen with other BS procedures. Obese women of childbearing age undergoing BS need to be aware of these outcomes.

Obstetrical and neonatal outcomes in women following gastric bypass: a Danish national cohort study

OBJECTIVE

To assess obstetrical and neonatal outcomes in women following gastric bypass, compared with adipose women without surgery and with a normal weight control population.

DESIGN

Historical controlled cohort study.

SETTING

Denmark.

POPULATION

All women undergoing gastric bypass during the period 1996-2011, and subsequently giving birth.

METHODS AND MAIN OUTCOME MEASURES

Obstetrical and neonatal outcomes in women without gastric bypass matched on age, parity, plurality, year, and body mass index, and normal weight women.

RESULTS

In 415 women giving birth after gastric bypass we found significantly more women with hypertension in pregnancy; relative risk (RR) 2.5 (95% confidence interval 1.3-5.0), gestational diabetes; RR = 6.9 (3.5-13.5), and acute abdominal pain during pregnancy; RR = 4.7 (2.9-7.8) compared with normal weight controls. Compared with women with similar body mass index, they had a lower incidence of preeclampsia and emergency cesarean sections, and their children a lower incidence of asphyxia; RR = 0.4 (0.2-0.8). Their children were on average 212 g smaller than newborn of normal weight mothers, and 319 g smaller than newborn of adipose controls, and had significantly more admissions to neonatal intensive care unit compared with newborn of normal weight mothers; RR = 1.5 (1.1-2.0).

CONCLUSIONS

Gastric bypass may reduce the risk of preeclampsia, emergency cesarean section, and perinatal asphyxia, compared with adipose women without surgery. Compared with normal weight controls women who had had a gastric bypass had a higher risk of hypertension, gestational diabetes, and acute abdominal pain during pregnancy and their children a lower birthweight and higher incidence of admittance to neonatal intensive care.

Pregnancy management following bariatric surgery

Bariatric surgery is gaining in popularity, due to globally increasing rates of obesity. In the UK, this has manifested as a 14-fold increase in bariatric surgery between 2004 and 2010, making it necessary to develop strategies to manage women who become pregnant following bariatric surgery. This review paper has explored all the current evidence in the literature and provided a comprehensive management strategy for pregnant women following bariatric surgery. The emphasis is on a multidisciplinary team approach to all aspects of care. Adequate pre-conception and antenatal and postnatal care is essential to good pregnancy outcomes with emphasis on appropriate nutritional supplementation. This is especially important following malabsorptive procedures. There is no evidence to suggest that pregnancy outcome is worse after bariatric surgery, though women who remain obese are prone to obesity-related risks in pregnancy. Neonatal outcome post-bariatric surgery is no different from the general population.

Mineral malnutrition following bariatric surgery

Moderate/severe obesity is on the rise in the United States. Weight management includes bariatric surgery, which is effective and can alleviate morbidity and mortality from obesity-associated diseases. However, many individuals are dealing with nutritional complications. Risk factors include: 1) preoperative malnutrition (e.g., vitamin D, iron); 2) decreased food intake (due to reduced hunger and increased satiety, food intolerances, frequent vomiting); 3) inadequate nutrient supplementation (due to poor compliance with multivitamin/multimineral regimen, insufficient amounts of vitamins and/or minerals in supplements); 4) nutrient malabsorption; and 5) inadequate nutritional support (due to lack of follow-up, insufficient monitoring, difficulty in recognizing symptoms of deficiency). For some nutrients (e.g., protein, vitamin B-12, vitamin D), malnutrition issues are reasonably addressed through patient education, routine monitoring, and effective treatment strategies. However, there is little attention paid to other nutrients (e.g., zinc, copper), which if left untreated may have devastating consequences (e.g., hair loss, poor immunity, anemia, defects in neuro-muscular function). This review focuses on malnutrition in essential minerals, including calcium (and vitamin D), iron, zinc, and copper, which commonly occur following popular bariatric procedures. There will be emphasis on the complexities, including confounding factors, related to screening, recognition of symptoms, and, when available, current recommendations for treatment. There is an exceptionally high risk of malnutrition in adolescents and pregnant women and their fetuses, who may be vulnerable to problems in growth and development. More research is required to inform evidence-based recommendations for improving nutritional status following bariatric surgery and optimizing weight loss, metabolic, and nutritional outcomes.

Obesity and reproductive function

Obesity is associated with multiple adverse reproductive outcomes, but the mechanisms involved are largely unknown. Obesity has been referred to as a "complex system," defined as a system of heterogeneous parts interacting in nonlinear ways to influence the behavior of the parts as a whole. Human reproduction is also a complex system; hence the difficulty in identifying the mechanisms linking obesity and adverse reproductive function. This review discusses the adverse reproductive outcomes associated with obesity and the mechanisms involved and concludes with a discussion of public health policy with respect to the treatment of infertility in obese women.