Nathalie Auger1,2,3, Marianne Bilodeau-Bertrand2, Rasmi M Tith2,4, Laura Arbour5. 1. Department of Social and Preventive Medicine, University of Montreal Hospital Research Centre, Montreal, Quebec, Canada. 2. Institut National de Santé Publique du Québec, Montreal, Quebec, Canada. 3. Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada. 4. School of Public Health and Health Systems, University of Waterloo, Waterloo, Ontario, Canada. 5. Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Abstract
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.
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.
Authors: Katinka M Snoek; Régine P M Steegers-Theunissen; Eric J Hazebroek; Sten P Willemsen; Sander Galjaard; Joop S E Laven; Sam Schoenmakers Journal: Hum Reprod Update Date: 2021-10-18 Impact factor: 15.610