The introduction of combination therapy and the impact it has had on improving the health of HIV-positive women, together with the enormous strides made in reducing the risk of transmission from mother to baby has led to more HIV-positive women contemplating having children.
Some will learn of their HIV-diagnosis at a routine antenatal visit. These women will be promptly referred for additional tests and informed of treatment options to safeguard their own health and the health of their unborn child.
Ideally, HIV-positive women will be seen by a specialist midwife and/or obstetrician throughout their pregnancy.
In 1993 (pre antiretroviral therapy) the transmission rate from mother to child was 19.6%. Today this rate has fallen to approximately 5% and some studies quote lower rates. The most significant factor to reduce rates has been the introduction of antiretroviral therapy.
From conception onwards there is a risk of viral transmission from mother to baby. However, the risk can be reduced substantially through a number of interventions.
The risk of transmission is increased if:
• The mother has high viral load (key factor); • She is older; • She smokes during pregnancy; • She has unprotected sex during pregnancy; • The mother uses illicit drugs during pregnancy; • She has no antiretroviral therapy during pregnancy and delivery; • Delivery is premature; • Membranes rupture more than 4 hours before delivery; • Delivery is natural and not by Caesarean section; • Delivery is prolonged or difficult; • A cervical or vaginal infection is present; • Membranes are inflamed; • The mother breastfeeds.
A high viral load substantially increases the risk of transmission to either a negative partner or an unborn child. For this reason the control of viral load from conception, throughout the pregnancy and during delivery by the use of antiretroviral therapy is crucial, which highlights the advantage of planning a pregnancy in advance.
There is no evidence to suggest that pregnancy accelerates HIV progression. It has been observed that CD4 counts drop in pregnancy, but this is also seen in HIV-negative women. CD4 counts usually return to a pre-pregnancy level soon after delivery.
