Pregnancy

Efavirenz can be used during pregnancy although experts in different countries and regions have arrived at different conclusions about when it is preferable to use it. Efavirenz is recommended as a preferred first-line drug in World Health Organization guidelines. National guidelines in the United Kingdom recommend newer drugs but do not recommend against the use of efavirenz during pregnancy. European guidelines recommend continuation of efavirenz during pregnancy; for women starting treatment during pregnancy efavirenz may be used if other options are not available. United States guidelines, last updated in 2016, recommend against the use of efavirenz in the first three months of pregnancy.

Previous treatment guidelines warned against the use of efavirenz during pregnancy based on findings from animal studies and a small number of case reports of neural tube defects in infants exposed to efavirenz during the first three months of gestation.¹

It is now clear that birth defects do not occur at a higher rate in infants exposed to efavirenz.

A systematic review and meta-analysis of 23 studies, published in 2014, found that treatment with efavirenz during the first three months of pregnancy did not increase the risk of birth abnormalities. Amongst children born to women who received efavirenz in the first trimester, the overall incidence of birth abnormalities was 1.6%, and the prevalence of neural tube defects was 0.05%. Both figures are very close to the ranges reported in the general population in many developed and developing countries.²