TOPLINE:
Pregnancy weight gain is lower in women with a history of gastric bypass or sleeve gastrectomy than in those without such a history, especially when the interval between surgery and conception is shorter, new data suggest.
METHODOLOGY:
- Using Swedish national registers, researchers investigated the association of pregnancy weight gain with history in 12,776 pregnancies — 6388 in women with a history of bariatric surgery and 6388 in women without such a history.
- Pregnancies were propensity score matched to patients’ early-pregnancy body mass index (BMI), prepregnancy diabetes, , smoking status, education, height, country of birth, and delivery year.
- Post-gastric bypass pregnancies were matched to post-sleeve gastrectomy pregnancies using the same matching strategy.
- Time from surgery to conception was also assessed.
TAKEAWAY:
- Across all early-pregnancy BMI strata, women with a history of bariatric surgery had lower pregnancy weight gain than matched controls.
- The magnitude of difference was largest for women with normal weight or overweight early-pregnancy BMI status (adjusted mean difference in z score, −0.33), which then decreased stepwise within the subclasses (−0.21, −0.16, and −0.08 for obesity classes I, II, and III, respectively).
- Pregnancy weight gain did not differ by surgery type, but lower pregnancy weight gain was associated with a shorter surgery-to-conception interval (particularly within 1 year) or lower surgery-to-conception weight loss.
IN PRACTICE:
“The highest proportion of weight gain below the recommendations was found among women with a normal weight status. Hence, clinical attention to women with history of bariatric surgery and a normal weight status in early pregnancy might be warranted,” the authors advised.
SOURCE:
The study, with the first author Huiling Xu, MD, MSc, Karolinska Institutet, Stockholm, Sweden, was published online in JAMA Network Open.
LIMITATIONS:
Despite rigorous matching, residual confounding was possible. The sample size was limited for some subgroups, possibly affecting statistical power. Although the study provides an overview of pregnancy outcomes within surgery-to-conception interval and pregnancy weight gain z scores, a more in-depth investigation is needed to understand the associations among bariatric surgery, pregnancy weight gain, and pregnancy outcomes.
DISCLOSURES:
Research for this study was supported by the Swedish Research Council for Health, Working Life and Welfare, and the Swedish Research Council. The authors have no relevant disclosures.
A version of this article appeared on Medscape.com.