Pregnancy and perinatal transmission

DEFINITION

• Without the use of preventive measures, the approximate risk of mother to child transmission (MTCT) of HIV is 15-30% for live births (mostly intrapartum) and 15% during breastfeeding. Taken together risk of HIV transmission during pregnancy, delivery, and breastfeeding is approximately 20-40%.
• Use of antenatal and post-natal prevention of mother to child transmission (PMTCT) reduces risk to < 1%.
• Risks of transmission include higher maternal VL, lower CD4 count, severe prematurity (< 33 wks), multiple gestation (twin A at higher risk), smoking, active HSV, genital ulcer disease.
• Pregnancy does not increase HIV progression, risk of OIs, or HIV-related survival. Hemodilution of pregnancy may cause apparent decrease in absolute CD4 (not CD4%).