One Day Old

Better Pregnancy Outcomes After Bariatric Surgery?

Obesity can be very real problem for women who want to have a baby. First of all, it can interfere with getting pregnant. Even when pregnancy becomes a reality, obesity can lead to problems. Preeclampsia, gestational diabetes, postpartum hemorrhage, cesarean delivery, excess fetal growth, stillbirth, congenital anomalies, and neonatal death are all more frequent issues in a pregnancy with obesity. So this question is important. Are pregnancy outcomes better for a woman with obesity if she has had bariatric surgery?

Prior research has been encouraging. It has made it clear that pregnancy after bariatric surgery is safe, if the patient waits for at least a year after their procedure. Now, a new study offers some genuinely good news. Though there are things to watch, the risk for bad outcomes generally goes down for women who have had bariatric surgery. But two exceptions are worth noting. One is the risk for having a small baby, which is about 2.5 times higher. The other risk that goes up is the risk for excessive blood loss.

A Study of 20,213 Pregnancies

This observational study of 20,213 pregnancy outcomes in patients from Kaiser of Southern California. All of the patients selected for study were good candidates for bariatric surgery, but only 9.3 percent of them had received it. This is actually a bit high. In the general population, it is more common to see only one or two percent of bariatric surgery candidates have the procedure.

In this sample, the most common procedure was the gastric sleeve, accounting for 47 percent of the patients in the bariatric surgery group. Another 45 percent had a gastric bypass.

Going into pregnancy, the women in the bariatric surgery group were generally healthier. Their BMI was significantly lower (35 vs 43). They had lower rates of high blood pressure and diabetes before they became pregnant.

So it is not terribly surprising that pregnancy went better for the women with a history of bariatric surgery. Even after adjusting for comorbidities, the risk of gestational diabetes was 40 percent lower. Preeclampsia and eclampsia risk went down by 47 percent. The risk of infections, excessively large babies, NICU admissions, and caesarian deliveries all went down, too. As we noted earlier, the only two risks that went up were the risks of having a small baby and the risk for excessive blood loss.

PCOS Outcomes

Polycystic ovary syndrome (PCOS) is another health concern that relates to pregnancy and obesity. This is a condition that can make becoming pregnant quite difficult. It can occur in women with or without obesity, but obesity makes it worse. Research published late last year tells us that bariatric surgery can lead to good outcomes for women with obesity and PCOS who want to have a baby.

This was an observational study of 216 premenopausal women who had bariatric surgery. The goal was to understand if fertility and pregnancy outcomes differed in these women whether or not they had PCOS. The bottom line was that it did not. Women with PCOS who wanted to become pregnant after surgery were just as likely to succeed. In fact, 95 percent of them did. Furthermore, complications for mother and child were few and no different for women with PCOS.

On balance, this is good news. Obesity can interfere with pregnancy in many ways. Bariatric surgery can help with better pregnancy outcomes down the road. However, research shows that it is best to avoid pregnancy for the first year after bariatric surgery.

Click here for the latest study of pregnancy outcomes after bariatric surgery and here for the study of PCOS and pregnancy after surgery. For further perspective, click here.

One Day Old, photograph by Carol Blyberg, licensed under CC BY-NC 2.0

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August 7, 2021