Some antibiotics linked with birth defects

Children of mothers prescribed macrolide antibiotics during the first trimester of pregnancy are at an increased risk of major birth defects when compared with penicillin, and the drugs should be used 'with caution' according to a new UCL study. The study, published today in The BMJ , aimed to assess the association between macrolides - a class of drugs used to treat common bacterial infections - and major malformations such as heart and genital defects, as well as four neurodevelopmental disorders (cerebral palsy, epilepsy, ADHD, and autism spectrum disorder) in children. Researchers analysed data from 104,605 children born in the UK from 1990 to 2016 using the Clinical Practice Research Datalink (CPRD) with a median follow-up of 5.8 years after birth. A further 82,314 children whose mothers were prescribed macrolides or penicillins before pregnancy, and 53,735 children who were siblings of children in the study group acted as control (comparison) cohorts. Major malformations were present in 186 children of 8,632 whose mothers were prescribed macrolides at any point during pregnancy and 1,666 of 95,973 children whose mothers were prescribed penicillins during pregnancy. After taking into account other influencing factors, the researchers found macrolide prescribing during the first three months (the first trimester) of pregnancy was associated with an increased risk of any major malformation compared with penicillin (28 versus 18 per 1,000 births ) and specifically cardiovascular malformations (11 v seven per 1,000 births).