Expectant mothers may have another thing to worry about when going into labor, especially if they believe they’re going to undergo a Cesarean section. A new study, published in the journal PLoS Medicine, has found that women who undergo the procedure have a slight future risk of stillbirth and ectopic pregnancy.

Although C-sections are far safer now than they were in the past, thanks to improved surgical practices and better antibiotics for recovery, they still come with risks, including infection, blood clots, increased bleeding, and inflammation of the membrane lining the uterus, according to Mayo Clinic. Women who undergo C-sections are actually 2.3 times more likely to visit the hospital with complications within 30 days of birth, when compared to women who undergo vaginal births. And there’s already evidence that future births in women who undergo C-sections will be marred with problems too, including bleeding and problems with the placenta, and uterine rupture.

The current study, which was conducted by researchers in Denmark and Ireland, found that women who had C-sections had a 14 percent higher rate of stillbirth during their next pregnancy when compared to women who have vaginal births. Overall, this translated into a 0.03 percent absolute risk, or one out of 3,000 women. Meanwhile, women who underwent a C-section were nine percent more likely to have an ectopic pregnancy when compared to those who had vaginal births, translating into a 0.1 percent absolute risk.

While the risks are indeed very low, Louise Kenny, of the University College Cork, Ireland, notes in a press release that they’re still “particularly important for expectant mothers as well as health care professionals as Cesarean section rates are increasing significantly worldwide.” In the U.S., C-section rates make up 32.8 percent of all deliveries. Though they remained relatively unchanged from 2009 to 2011, there was a 60 percent increase from the most recent low of 20.7 percent in 1996, according to the Centers for Disease Control and Prevention.

The researchers’ findings were the result of looking at data on almost 833,000 women from the Danish national registers. The team looked at information on their first live births and whether they had C-sections, and then followed up with the women when they had subsequent pregnancies to determine if any of them had a stillbirth, miscarriage, ectopic pregnancy, or, normally, a live birth. Their analysis accounted for women who had C-sections due to complications affecting their early pregnancy.

While some women must undergo a C-section, the researchers believe their findings will “assist women and health care providers to reach more informed decisions regarding mode of delivery,” they wrote.

Source: O’Neill S, Agerbo E, Kenny L, et al. Cesarean Section and Rate of Subsequent Stillbirth, Miscarriage, and Ectopic Pregnancy: A Danish Register-Based Cohort Study. PLoS Medicine. 2014.