Poster Presentation Australasian Diabetes in Pregnancy Society Annual Scientific Meeting 2024

Gestational diabetes mellitus post-bariatric surgery: a cohort study and literature review (#26)

Jasmine Wintour 1 2 , Sarjana Afrin 2 3 , Nicole Buxton 4 , Mercy Madzivanyika 5 , Katie Wynne 1 2 6
  1. Department of Diabetes and Endocrinology, John Hunter Hospital, Newcastle, New South Wales, Australia
  2. University of Newcastle, Newcastle, New South Wales, Australia
  3. Department of General Medicine, John Hunter Hospital, Newcastle, New South Wales, Australia
  4. Department of Nutrition and Dietetics, John Hunter Hospital, Newcastle, New South Wales, Australia
  5. Department of Obstetrics and Gynaecology, , John Hunter Hospital, Newcastle, New South Wales, Australia
  6. ‘Equity in Health & Wellbeing’ Program, Hunter Medical Research Institute, Newcastle, New South Wales, Australia

Background: With the upsurge of obesity both in Australia and worldwide, the number of bariatric surgeries is increasing globally, including in women of reproductive age[1]. Bariatric surgery reduces rates of Gestational Diabetes Mellitus (GDM) compared to women with obesity at pre-surgery weight, but rates remain above background risk for all pregnancies[2].

Objective: (A) to evaluate maternal and perinatal outcomes of consecutive women with GDM post-bariatric surgery presenting to an endocrine antenatal clinic in a single tertiary centre; (B) to review the literature reporting on women with GDM after bariatric surgery, including diagnosis and glycaemic targets.

Methods: A retrospective cohort study of women with GDM after bariatric surgery delivering at John Hunter Hospital was audited between 2020 to 2024. PubMed was searched from 2010 to April 2024 using keywords Gestation/Pregnancy/Antenatal AND Bariatric Surgery/Metabolic Surgery/Gastric Sleeve/ Gastric Bypass AND Gestational Diabetes and data extracted on the incidence and prevalence of GDM and diagnostic and management approaches.

Results: A cohort of 36 women, aged 32.9[+/-4.7SD] years, 3.3[+/-2.SD] years post-surgery, included 34 women with a sleeve gastrectomy, one with gastric band and subsequent sleeve gastrectomy, and one with gastric bypass. Of this cohort, 17% reported hypoglycaemia pre-pregnancy. GDM was diagnosed at 25[+/-6.0SD] weeks, three using OGTT, resulting in one hypoglycaemic event. Insulin therapy was required in 44.4%, with a total daily dose of 20[+/-13.0SD] units. Recurrent hypoglycaemia occurred in ten (27.8%) women and limited insulin titration in six (16.7%). Women birthed at 38[+/-1.0SD] weeks, with caesarean section in 47.2% (unplanned 35.3%). Adverse neonatal outcomes occurred in 61.1% of births (a composite of shoulder dystocia, resuscitation, respiratory distress, NICU admission, neonatal hypoglycaemia, jaundice, small or large for gestational age).  Neonatal hypoglycaemia (<2.6mmol/l) occurred in 22.2% of neonates; 2.8% were small-for-gestational age, and 5.6% were large-for-gestational age. A higher neonatal birthweight was observed in women with reported pre-pregnancy BMI ≥30kg/m2 (3369g vs. 3132g, p=0.044) and in women requiring insulin (3418g vs. 3153g, p=0.022). Women with recurrent hypoglycaemia had smaller babies than women without hypoglycaemia (3104g vs 3334g, p=0.077).

Sixty-seven articles were identified and reviewed in full, but no specific guidelines were identified for diagnosis or management. Utilisation of CGM may be useful to improve safety and outcomes post-bariatric surgery[3][4][5]. Gestational weight gain may be useful to stratify materno-foetal risk[69].

Conclusion: Further research is required to evaluate optimal methods of screening and glycaemic targets for GDM in women after bariatric surgery.

  1. Angrisani L, Santonicola A, Iovino P, Palma R, Kow L, Prager G, Ramos A, Shikora S; Collaborative Study Group for the IFSO Worldwide Survey. IFSO Worldwide Survey 2020-2021: Current Trends for Bariatric and Metabolic Procedures. Obes Surg. 2024 Apr;34(4):1075-1085. doi: 10.1007/s11695-024-07118-3. Epub 2024 Mar 4. PMID: 38438667; PMCID: PMC11026210.
  2. Adam S, Ammori B, Soran H, Syed AA. Pregnancy after bariatric surgery: screening for gestational diabetes. BMJ. 2017 Feb 3;356:j533. doi: 10.1136/bmj.j533. PMID: 28159743.
  3. Cummings C, Jiang A, Sheehan A, Ferraz-Bannitz R, Puleio A, Simonson DC, Dreyfuss JM, Patti ME. Continuous glucose monitoring in patients with post-bariatric hypoglycaemia reduces hypoglycaemia and glycaemic variability. Diabetes Obes Metab. 2023 Aug;25(8):2191-2202. doi: 10.1111/dom.15096. Epub 2023 May 3. PMID: 37046360; PMCID: PMC10807851.
  4. Majewska A, Stanirowski PJ, Tatur J, Wojda B, Radosz I, Wielgos M, Bomba-Opon DA. Flash glucose monitoring in gestational diabetes mellitus (FLAMINGO): a randomised controlled trial. Acta Diabetol. 2023 Sep;60(9):1171-1177. doi: 10.1007/s00592-023-02091-2. Epub 2023 May 10. Erratum in: Acta Diabetol. 2023 Oct;60(10):1439. doi: 10.1007/s00592-023-02159-z. PMID: 37160787; PMCID: PMC10359198.
  5. Bonis C, Lorenzini F, Bertrand M, Parant O, Gourdy P, Vaurs C, Cazals L, Ritz P, Hanaire H. Glucose Profiles in Pregnant Women After a Gastric Bypass : Findings from Continuous Glucose Monitoring. Obes Surg. 2016 Sep;26(9):2150-2155. doi: 10.1007/s11695-016-2061-z. PMID: 26757924.