Bariatric weight loss surgery can be a good option for people who battle obesity. But new research published in the British Medical Journal suggests that women who undergo this procedure and later become pregnant are more likely to deliver premature or low-birth-weight babies, The New York Times reports.

For the study, Swedish researchers reviewed 15,000 births between 1992 and 2009, including 2,500 babies born to women who had undergone bariatric surgery. (On average, these women delivered about five years after receiving the weight-loss procedure.)

After setting controls for age, smoking and other environmental risk factors, researchers found that about 10 percent of children born to moms who had undergone weight loss surgery were premature, compared with only 6 percent in the nonsurgical group.

In addition, 5 percent of children born to mothers in the surgery group were considered underweight, compared with 3 percent among mothers who had not undergone bariatric surgery.

Researchers suggested that these birth problems could be caused by vitamin and mineral deficiencies that sometimes occur after weight-loss surgeries. (These factors can directly affect fetal and placental growth.)

But scientists also noted one major health advantage among children of the mothers who underwent bariatric surgery. These moms were less likely to deliver overweight or excessively large babies because the surgery improves their blood sugar levels and insulin resistance. (Both conditions are strongly linked to mothers having too-big babies.)

Real Health suggests women carrying too many pounds seriously weigh both sides of the debate regarding obesity and bariatric surgery before making the decision to have a child.

For more information about how a mother’s weight can affect the long-term health of her baby, click here.