The effectiveness of the nucleoside reverse transcriptase inhibitor (NRTI) known as AZT in reducing transmission rates has been established since 1994. AZT is taken orally after the 14th week of pregnancy and intravenously during labour. In addition, administering AZT syrup to newborns for the first six weeks can further reduce transmission.
For women who are already taking antiretroviral therapy and then discover they are pregnant after 14 weeks, it is usually advised that they continue with the established therapy as well as AZT. If pregnancy is confirmed prior to 14 weeks, it may be advisable to discontinue antiretroviral therapy until after 14 weeks - this should be discussed with the doctor.
Although not licensed for use in HIV-positive pregnant women, nevirapine as a one-off dose is sometimes used (more so in developing countries). The drug has been shown to reduce the risk of mother-to-baby transmission.
Combivir has also been used on HIV-positive pregnant women. However, recent studies in Africa showed that some HIV-positive pregnant women taking Combivir had damaged cells in their umbilical cord and the cord’s blood supply. The long-term effect of what this will mean to their children is not yet known.
For women who are already taking antiretroviral therapy and then discover they are pregnant after 14 weeks, it is usually advised that they continue with the established therapy as well as AZT. If pregnancy is confirmed prior to 14 weeks, it may be advisable to discontinue antiretroviral therapy until after 14 weeks - this should be discussed with the doctor.