HIV-positive mothers can protected their babies from becoming infected with the virus if they take antiretroviral drugs during pregnancy. However, even though these drugs prevent transmitting the disease to the child, they could potentially cause birth defects like cleft lip and palate. A new study, published in the January edition of Cleft Palate- “Craniofacial Journal, has investigated the association between antiretroviral prophylaxis and cleft lip and palate.

To establish a potential link between drugs and birth defects using “reporting odds ratios”, the researchers examined 5 years of data from the U.S. Food and Drug Administration’s Adverse Events Reporting System (AERS), which is a publicly available database with resources for pharmacovigilance.

Antiretroviral drug treatment has been able to decrease the risk of HIV transmission from mother to child from 15 to 25% to less than 1%, but even though this success rate means that antiretroviral medications are now used as standard therapy, none of these drugs have been classed as safe, i.e. as category A drugs, safe for use in pregnancy. Investigations must therefore be continued to assess the potential risks for unborn children.

The findings of the new study identified 26 incidents of cleft lip and palate related to seven antiviral drugs, namely efavirenz, lamivudine, nelfinavir, and the combination of abacavir/sulfate/laminudine/zidovudine. Despite the fact that these drugs were reported to have substantially high odds ratios, it there is no evidence that they cause the deformities, however, they do serve as an indicator for a potential link.

Cleft lip and palate is a hereditary malformation thought to have several causes, such as genetic and environmental factors. However poor nutrition, including excess vitamin A intake and a deficiency of other vitamins and minerals can also contribute to its development. Further research is required to establish whether an association between antiretroviral medications and cleft lip and palate exists.

Written By Petra Rattue