Oral Presentation ESA-SRB-ANZBMS 2024 in conjunction with ENSA

Pregnancy and offspring outcomes according to pre-pregnancy bariatric surgery to conception interval (#89)

Jade Eccles-Smith 1 2 , Allison Griffin 3 , David McIntyre 2 4 , Marloes Dekker Nitert 5 , Helen Barrett 2 6 7
  1. Obstetric Medicine, Royal Brisbane and Women's Hospital, Herston, QLD, Australia
  2. Mater Medical Research Institute, South Brisbane, QLD, Australia
  3. QIMR Berghofer Medical Research Institute, Herston, QLD, Australia
  4. Obstetric Medicine, Mater Health Services, South Brisbane, QLD, Australia
  5. School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
  6. Obstetric Medicine, Royal Hospital for Women, Randwick, NSW, Australia
  7. Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia

In Australia, bariatric procedures doubled between 2005 and 2015 with 80% performed on women of childbearing age.(1) Following surgery, the ideal time interval to pregnancy is controversial, current recommendations are a minimum of 12 months to minimize the theoretical risks of malnutrition and impaired fetal growth.(2,3) This data-linkage project compared the pregnancy and neonatal outcomes of women with a pre-pregnancy bariatric surgery to conception interval of <12 months and ≥12 months.

A statewide data registry linked cohort matched study was performed. The first, singleton, pregnancy following bariatric surgery was analyzed (n=383 women <12 months between surgery and conception and n=899 ≥12 months). Continuous variables were compared between groups using the Wilcoxon rank-sum test or independent t-test and categorical variables were compared using Pearson’s Chi-square or Fisher’s exact test.

Women with a surgery to conception interval of ≥12 months were more likely to have gestational diabetes mellitus (16.8% vs 11.0%;p=0.01) and pregnancy-induced hypertension (4.4% vs 1.8%;p=0.02) but had less nausea and vomiting (1.4% vs 3.9%;p=0.01) than women who conceived <12 months from bariatric surgery. Neonates born to women with a surgery to conception interval of ≥12 months had higher absolute birthweights 3270g (interquartile range 2970-3610);p=0.001) vs (3160g (2860-3510), but no difference in rates of large for gestational age (6.8% vs 9.4%;p=0.14) or small for gestational age (SGA) (12.4% vs 10%;p=0.22). There were no differences in pre-term delivery, neonatal nursery admission or congenital anomalies between groups.

Our results suggest that pregnancy outcomes following a surgery to conception interval of <12 months differ from those ≥12 months. However, rates of congenital anomalies, LGA, SGA, pre-term delivery and neonatal nursery admissions were not different between groups.  Gestational weight gain may contribute to the alterations in pregnancy and neonatal outcomes; however physiologic adaptations following surgery may also be involved.

  1. 1. AIHW, Weight loss surgery in Australia 2014–15: Australian hospital statistics. 2017.
  2. 2. Mechanick JI, Youdim A, Jones DB, Garvey WT, Hurley DL, McMahon MM, et al. Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient-2013 update: Cosponsored by American association of clinical endocrinologists, the obesity society and American society for metabolic & bariatric surgery. Obesity. 2013;21(SUPPL. 1):S1-S27.
  3. 3. Heber D, Greenway FL, Kaplan LM, Livingston E, Salvador J, Still C. Endocrine and nutritional management of the post-bariatric surgery patient: an Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2010;95(11):4823-43.