Pregnancy Linked To Macrolide Antibiotics With Risk Of Birth Defects

Pregnancy linked to macrolide antibiotics with risk of birth defects

Taking antibiotics of the macrolide group in early pregnancy is associated with an increased risk of congenital malformations in children. Their use before pregnancy and in later stages was not associated with such a hazard.

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Taking antibiotics of the macrolide group in early pregnancy is associated with an increased risk of congenital malformations in children. This was shown by a major UK study published in The BMJ.

Macrolides (erythromycin, clarithromycin, azithromycin) are widely used to treat common bacterial infections, including sexually transmitted infections. As a rule, it is they who are prescribed to people with an allergy to penicillin.

Researchers from University College London studied data from more than 180,000 children whose mothers took either penicillin or a macrolide antibiotic during pregnancy or in the year before. When analyzing the information, potential risk factors for the occurrence of congenital malformations were taken into account: such as alcohol or drug use, smoking, hypertension and diabetes.

The researchers found that compared to taking penicillin in the first trimester of pregnancy, using macrolides increased the relative risk of having a baby with birth defects of the nervous, cardiovascular, gastrointestinal, or genitourinary systems by 55%. The risk of congenital malformations of the cardiovascular system was especially high.

The use of macrolides before pregnancy or at a later date (in the second or third trimesters) in this study was not associated with an increase in the likelihood of congenital malformations in children. Researchers found no association between macrolide use and an increased risk of cerebral palsy, epilepsy, ADHD, or autism spectrum disorders.

However, the authors noted that pregnant women with bacterial infections should not give up antibiotics, as the absence of treatment can be much more dangerous to the fetus.

"But our results indicate that it is better to avoid macrolides if other antibiotics can be used," recommended Heng Fan, lead author of the study.

Previously, some studies have indicated the relative safety of using this group of antibiotics in the first trimester.