Oral Presentation Australasian Diabetes in Pregnancy Society Annual Scientific Meeting 2024

Pregnancy and offspring outcomes according to pre-pregnancy bariatric surgery to conception interval (107310)

Jade Eccles-Smith 1 2 3 , Alison Griffin 4 , H.David McIntyre 1 5 , Marloes Dekker Nitert 6 , Helen L Barrett 7 8 9
  1. Mater Research, - The University of Queensland, South Brisbane
  2. Department of Obstetric Medicine, The Royal Brisbane and Women's Hospital, Herston
  3. Department of Endocrinology, The Royal Brisbane and Women's Hospital, Herston, QLD, Australia
  4. QIMR Berghofer Medical Research Institute, Herston
  5. Obstetric Medicine, Mater Health, South Brisbane
  6. School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane
  7. Mater Research, South Brisbane
  8. Royal Hospital for Women, Randwick
  9. Medicine, University of New South Wales, Sydney

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 Maternal and fetal outcomes however, to date are heterogenous. This data-linkage project analysed the pregnancy and neonatal outcomes of women with a pre-pregnancy bariatric surgery to conception interval of <12 months and ≥12 months.

A statewide hospital and perinatal data register linked cohort matched study was performed.

A total of n=1282 singleton, first pregnancies following bariatric surgery were analyzed with n=383 surgery to conception interval of less than 12 months and n=899 ≥12 months. Continuous variables were analyzed using Mann-Whitney U test or independent t-tests and categorical variables were analyzed using Pearson’s Chi-square or Fisher’s exact test.

Women with a surgery to conception interval of ≥12 months were more likely to be older (p<0.001) and nulliparious (12.7% vs 26.2%;p<0.001) than women who conceived within 12 months of surgery. They were also more likely to have gestational diabetes mellitus (GDM) (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 of pregnancy (1.4% vs 3.9%;p=0.01) compared to women who conceived <12 months from pre-pregnancy bariatric surgery. Neonates born to women with a surgery to conception interval of <12 months had lower absolute birthweights (3160g (2860-3510) vs 3270g (2970-3610);p=0.001), lower rates of large for gestational age (LGA) (6.8% vs 9.3%; p=0.049) but, no difference in rates of small for gestational age (SGA). 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. Reassuringly rates of congenital anomalies, 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.

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  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.