Key Findings: Antibiotic Use among Women with Urinary Tract Infections in the First Trimester of Pregnancy and Birth Defects

The journal Birth Defects Research (Part A) has published a study looking at the relationship between reported antibiotic use among women with kidney, bladder, or just urinary tract infections (all referred to as UTIs) just before or during the first trimester of pregnancy and birth defects. The findings showed that women who used the antibiotics trimethoprim-sulfamethoxazole, nitrofurantoin, or cephalosporins were at higher risk for one or more major birth defects, as compared to women who only took penicillin. Read the scientific summary of the study.

Untreated UTIs can cause serious problems for the mother and baby during pregnancy. Therefore, women should consult their doctors and seek treatment if they suspect they might have a UTI. Despite these study findings, it is important to remember that individual birth defects are rare, and women and their doctors should work together to make any treatment decisions.

Main Findings

• About one in 13 women reported having a doctor-diagnosed, fever-free UTI just before or during pregnancy.
• Among women with a UTI, a majority of them reported taking an antibiotic medication.

About This Study

• The National Birth Defects Prevention Study (NBDPS) is a population-based, multi-site study, which aims to understand factors that might increase the risk for major birth defects. The study included interviews with mothers of babies with and without birth defects.
• The study group included children born between October 1997 and December 2011. Birth defects were identified through birth defects tracking systems in the entire state of Arkansas, Iowa, New Jersey, and Utah, and in select counties in California, Georgia, Massachusetts, North Carolina, New York, and Texas.
• Researchers studied women who reported having a UTI just before or during the first trimester (first three months) of pregnancy and assessed whether their reported use of an antibiotic was linked to having a baby with a major birth defect.
• Researchers looked at women who took one of the following types of antibiotics for a UTI: penicillins, nitrofurantoin, trimethoprim-sulfamethoxazole, and cephalosporins. They compared women with UTIs who took penicillins to women with UTIs who reported taking nitrofurantoin, trimethoprim-sulfamethoxazole or cephalosporins.

Medication Use during Pregnancy: CDC’s Activities

CDC’s National Center on Birth Defects and Developmental Disabilities (NCBDDD) is working to improve the health of women and babies. Through its Treating for Two: Safer Medication Use in Pregnancy initiative, CDC is working with its partners, other federal agencies, and the public to

• Understand trends in medication use among pregnant women and women of reproductive age; and
• Provide women and healthcare providers with information about the safety or risk of using specific medications during pregnancy.

This information will allow women and their healthcare providers to make informed decisions about treating health conditions during pregnancy.

Treating for Two focuses on the following activities:

• Better research: Expanding and accelerating research to fill gaps in knowledge about medication use before and during pregnancy.
• Informed decisions: Delivering up-to-date information to support decision-making among prescribers of medications, pharmacists, and the public.
• Reliable guidance: Evaluating scientific evidence to provide reliable guidance.

Pregnant women should not stop or start taking any medications without first talking with a healthcare provider. Women who are planning to become pregnant should discuss the need for any medication with their healthcare provider and ensure that they are taking only medications that are necessary.

More Information

• For more information about medications and pregnancy, visit www.cdc.gov/pregnancy/meds or www.cdc.gov/treatingfortwo
• Have questions about how medications you are taking may affect a pregnancy? MotherToBaby.org can help you find the answers.

Key Findings Reference

Ailes EC, Gilboa SM, Gill SK, Broussard CS, Crider KS, Berry RJ, Carter TC, Hobbs CA, Interrante J, Reefhuis J, and the National Birth Defects Prevention Study. (2016). Association between Antibiotic Use among Pregnant Women with Urinary Tract Infections in the First Trimester and Birth Defects, National Birth Defects Prevention Study 1997-2011. http://onlinelibrary.wiley.com/doi/10.1002/bdra.23570/full