Does Bariatric Surgery Lead to Safer Pregnancies?

A new study of whether bariatric surgery leads to safer pregnancies is stirring some excitement, because it offers the best insight yet on this question. The trouble is that the findings don’t fit neatly into a sound bite or a headline. It looks like the pregnancy is safer for the mother. But for the baby, the answers are not as clear. The study was just published in the New England Journal of Medicine.

Specifically, they found that mothers who had bariatric surgery before pregnancy were two-thirds less likely to develop gestational diabetes. The risk of delivering an excessively large baby was less than half what it was for matched controls who hadn’t had bariatric surgery. But infants born to mothers who had had surgery were about twice as likely to be smaller than normal. The researchers also observed a somewhat higher rate of infant mortality that fell short of being statistically significant.

With such mixed results, the accuracy of news reporting was mixed. Reuters hit the mark, saying “Weight-loss surgery tied to pregnancy benefits, risks.” Medscape missed it, saying “Preconception bariatric surgery may cut risks for mom, fetus.”

As good as it is to have these data, they don’t provide the whole picture. Even though this study has matched controls, it’s still just an observational study. That means it doesn’t really prove cause and effect. Since most of the women in the surgery group had gastric bypass procedures, these results don’t tell us anything about pregnancy outcomes with gastric bands or sleeves. And it’s important to consider the primary benefits of surgery — apart from its impact on pregnancy — for the mother. Better health, longer life, and better quality of life are some of the primary reasons for considering bariatric surgery.

In the end, these are intensely personal decisions. The best advice is to consider all the information you can and to talk it over with a trustworthy healthcare professional.

Click here to read more from Reuters, here to read the study, and here to read the editorial that accompanies it in the NEJM.

Baby Angel Love, photograph © joeannenah / flickr

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