Prevention of vertical transmission of HIV

Vertical transmission can be reduced if HIV is detected before or during pregnancy.

The risk of transmission of HIV from mother to newborn is around 20% which can be reduced to less than 1% with appropriate interventions (1). Interventions used in preventing vertical transmission are:

• giving antiretroviral therapy during
  • pregnancy
  • delivery and a short course for the baby
• elective cesarean section (although in women with very low viral loads this intervention could be questionable)
• avoiding breast feeding (1)
  
  

Zidovudine treatment reduces this risk to 8%. The regimen consists of:

• oral zidovudine during pregnancy
• intravenous zidovudine during labour
• oral zidovudine for the infant for six weeks

A trial by Lallement et al. suggests that prolonged zidovudine therapy of the infant may not have additional benefit if the mother has received a long regimen of zidovudine during pregnancy. Conversely if the antenatal treatment period is shortened, the six week course for the infant is likely to be beneficial.

In countries with adequate resources combination drugs are now widely used.

Reference:

• (1) The Medical Foundation for AIDS & Sexual Health (MedFASH) 2005. HIV in primary care: an essential guide to HIV for GPs, practice nurses and other members of the primary healthcare team