Does Gastric Sleeve Surgery Affect Pregnancy Outcomes?
A 2026 Australian study found that women who had previously had a gastric sleeve, also called a sleeve gastrectomy, experienced lower rates of certain pregnancy complications compared to a similar group who had not had weight loss surgery. The study also found that these pregnancies had a higher rate of babies born smaller than expected.
Who Was Studied and What the Researchers Set Out to Learn
The researchers reviewed records from 2016 to 2022, covering 469 pregnancies in women who had previously had a sleeve gastrectomy and 915 pregnancies in women who had not had bariatric surgery. The two groups were carefully matched to be similar in age, pre-pregnancy body weight, smoking status and other factors. This was a retrospective study, meaning it drew on existing records rather than following participants forward in real time.
Lower Rates of Some Complications Were Found, but the Risk of a Smaller Baby Was Higher
Women in the sleeve gastrectomy group had a notably lower rate of gestational diabetes, a form of high blood sugar that develops during pregnancy, at around 5 in 100 compared to about 17 in 100 in the matched control group. Rates of high blood pressure during pregnancy were also lower in the sleeve gastrectomy group. However, women who had previously had a sleeve gastrectomy were nearly twice as likely to have a baby that was smaller than expected for its stage of pregnancy.
This Study Has Useful Findings but Also Clear Limits Worth Knowing About
Because it was retrospective and not a randomised trial, the study can show associations between sleeve gastrectomy and pregnancy outcomes, but it cannot always explain the reasons behind them. The researchers suggested the higher rate of smaller babies may be connected to unrecognised low blood sugar or nutrient deficiency after surgery, though this was not confirmed. The study was conducted in Australia, which makes its findings particularly relevant to a local setting, but results will vary from person to person.
About this research: Perinatal Outcomes After Sleeve Gastrectomy Compared to a Matched Control Group, published in the Australian and New Zealand Journal of Obstetrics and Gynaecology, 2026. Read the study summary
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