Sulfatrim and Pregnancy

Taking Sulfatrim While Pregnant: An Introduction

Sulfatrim^® (sulfamethoxazole/trimethoprim) is a prescription antibiotic often used to treat urinary tract infections (UTIs), although it is approved for several other uses as well. At this time, it is not clear if Sulfatrim is safe for use during pregnancy.

 

Pregnancy Category C

The U.S. Food and Drug Administration (FDA) uses a pregnancy category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Pregnancy Category C is given to medicines that have not been studied in pregnant humans, but do appear to cause harm to the fetus in animal studies. Also, medicines that have not been studied in any pregnant women or animals are automatically given a pregnancy Category C rating. A pregnancy Category C medicine may be given to pregnant women if the healthcare provider believes that the benefits to the pregnant woman outweigh any possible risks to the unborn child.

 

In animal studies, Sulfatrim increased the risk of cleft palate. Also, trimethoprim (one of the components of Sulfatrim) increased the risk of fetal death in rats. Limited human data suggests that the risk for birth defects is probably low in humans. Because it is thought that Sulfatrim might contribute to birth defects by decreasing folic acid, a folic acid supplement (at a higher-than-normal dose for a pregnant woman) might be helpful if a pregnant woman needs to take Sulfatrim.

 

Of possibly greater concern, Sulfatrim might increase the risk of jaundice and, theoretically, kernicterus (brain damage caused by severe jaundice) in the newborn, especially if a pregnant woman takes Sulfatrim late in pregnancy.