HIV and pregnancy
What are the risks of mother having HIV in pregnancy?
The baby of a mother who is HIV positive may become infected with HIV during pregnancy, labour, birth or during breastfeeding. An HIV-infected mother taking HIV medication during pregnancy and birth can reduce the risk of passing HIV to their infant.
Pregnancy does not worsen HIV or increase the risk of death from HIV. It is not clear if HIV or HIV treatments increase the risk of pregnancy complications, such as prematurity, low birth weight, and stillbirth. However, it is very clear that HIV medications can significantly reduce the risk that the newborn will become infected with HIV when taken during pregnancy and labour, and then given to the newborn after delivery.
Care during pregnancy
Care during pregnancy is usually provided by an HIV specialist, a midwife and an obstetrician. During the initial evaluation, blood tests are performed to determine the amount of HIV virus in the mother's blood (e.g. HIV viral load) and the strength of the immune system (e.g. the number of CD4 T cells).
During pregnancy, most women with HIV are advised to take antiretroviral medication using up to three HIV drugs. When possible, zidovudine (ZDV) is included because it has been shown to significantly reduce the risk of passing HIV to the infant and is thought to be safe to take during pregnancy.
Timing of HIV medications
The mother's immune status determines when HIV medications are commenced. If HIV treatment is required for the mother's health it is started immediately. Otherwise, HIV medications are generally started after the first 12 weeks of pregnancy to avoid unnecessary drug exposure to the baby. Once started, HIV medications are continued throughout pregnancy to prevent HIV transmission to the baby.
Sometimes zidovudine is not used during pregnancy, but it may still be recommended during birth and for the baby for six weeks after birth.
It is extremely important to take HIV medications exactly as prescribed during pregnancy to decrease the risk of the mother developing drug resistance and to lessen the risk of HIV transmission to the baby.
Monitoring during pregnancy
Throughout pregnancy, routine obstetric care is provided in addition to HIV monitoring, including blood testing of both CD4 counts and HIV viral load. A follow-up ultrasound is sometimes recommended during the second and/or third trimester to monitor the growth of the baby.
Labour and birth with HIV
Medications during labour
Zidovudin is usually given during labour or at the time of caesarean birth, because it helps to reduce the risk of HIV transmission. Other antiretroviral drugs are also continued on schedule during labour or before a caesarean birth; this helps to provide maximum protection to the mother and infant.
Many factors contribute to decision making about the safest way for women with HIV to birth her baby including her HIV viral load. This can change during the pregnancy and for this reason the viral load is usually measured close to the due date and a discussion with the obstetrician occurs soon after to decide about vaginal or caesarean birth.
Pregnant women with HIV who have been taking HIV medications throughout pregnancy and have an undetectable HIV viral load at 34 to 36 weeks of pregnancy are recommended to plan for vaginal birth if there are no other reasons to avoid this type of birth. In this situation, the risk of transmitting HIV to the infant is very low, and there is no evidence that a caesarean birth will decrease this risk any further.
The benefit of a scheduled caesarean birth is that it minimises the infant's exposure to the mother's blood and vaginal fluids in the birth canal. This is important where mother's viral load is high. The risks for mother are that a caesarean birth can lead to complications (bleeding, infection, etc.), and recovery afterward may take longer compared with a vaginal delivery.
Because caesarean birth carries increased risks for the mother it is only recommended if there is clear evidence that the baby would benefit from being delivered by this method; however, there is still some uncertainty at some levels of viral load and therefore the pros and cons of both a vaginal or caesarean birth are discussed in detail at 36 weeks, before the mother makes her decision.
Care after birth
The HIV specialist will advise about management of HIV medications for the mother after birth.
Breastfeeding is not recommended
Women with HIV can pass HIV to their infant during breastfeeding. The risk of HIV transmission through breast milk can be lowered by HIV medications, but HIV can still be transmitted through breast milk; therefore, in Australia breastfeeding is not recommended.
HIV treatment for newborns and infants
Newborn babies of women with HIV are usually treated with zidovudine for the first six weeks of life. Zidovudine can help prevent the infant from becoming infected with HIV as a result of exposure to the mother's blood during birth.
Mater acknowledges consumer consultation in the development of this patient information.
Last modified 16/11/2015.