While these factors play a significant role in preventing vertical transmission, they are not exhaustive, nor do they provide long-term HIV treatment plans for expectant mothers.
The mother's immune health may be one of the most important factors influencing the risk of HIV transmission. Some studies show that transmission more likely occurs in women with more advanced HIV disease, high viral loads and/or lower CD4+ cell counts (especially below 200). However, no exact threshold accurately predicts whether or not transmission will occur. Thus, it's probably more useful to look at the viral load and CD4+ cell count to determine the health of the mother.
Many women with HIV also live with other infections, such as hepatitis C or herpes. Infection with these and other viruses may increase risk of HIV transmission. For example, HIV-positive pregnant women with genital herpes are more likely than HIV-negative women with genital herpes to have a herpes outbreak during labor. Genital sores associated with herpes outbreaks shed high levels of HIV, even when viral load in blood (measured by a viral load test) is below the limit of detection. An infant of an HIV-positive mother with recurrent genital herpes faces the risk of exposure to herpes and an increased risk of exposure to HIV. Thus, anti-herpes drugs may prevent a herpes outbreak during labor and may lower transmission risk.
Access to and use of prenatal care increases the likelihood that a woman will experience a healthier pregnancy and deliver a healthy, HIV-uninfected baby. In addition to traditional prenatal concerns of nutrition, exercise and lifestyle, prenatal care for positive women should consider the HIV issues of both mother and unborn baby. These include charting viral load and CD4+ cell counts, performing other routine tests and balancing the risks and benefits of anti-HIV therapy during pregnancy.
Aside from considering anti-HIV therapy, positive women should largely expect their pregnancy and labor to proceed as if they were HIV-negative. However, certain tests and procedures that are a routine part of prenatal care for HIV-negative women should be avoided if possible.
Pregnancy is a time of change in body, mind and lifestyle. Good prenatal care should also include appropriate education, counseling and referrals to services which offer help with these changes and encourage making choices to ensure a healthy pregnancy. For example, street drugs adversely affect women's health, their pregnancies and their developing babies. Babies exposed to street drugs in utero often have abnormalities in their development, low birth weight or premature delivery.
Street drugs, particularly injection drug use and crack-cocaine, are also associated with increased vertical transmission rates. The risk of vertical transmission and complications associated with using street drugs can be significantly decreased when pregnant women get into early prenatal care and drug abuse programs during pregnancy. Prenatal care providers should discuss the enormous adverse health effects that street drugs (as well as alcohol use and cigarette smoking) hold during pregnancy. They should also provide referrals to resources dedicated to helping women to kick addictions.
Similarly, it is important to consider one's home life when developing an optimal pregnancy care plan. A regrettably common example of this includes domestic violence. About one quarter of women seeking prenatal care report abuse by their partners. Domestic violence specialists estimate the rate of abuse among HIV-positive pregnant women may be even higher, particularly among young women.
Women who are abused during pregnancy suffer greatly, as do their babies. Battered women are at increased risk for poor weight gain, infection, bleeding, anemia and substance abuse during pregnancy. Babies born to abused women are more likely to be underweight and premature. All of these outcomes are associated with increased risk of vertical transmission. Help is available for women who are victims of domestic violence.
HIV is present in breast milk. Researchers estimate a 29% transmission rate from HIV+ mothers who consistently breast-feed their children. It is unclear whether and to what degree anti-HIV treatment changes this rate. Women with safe alternatives to breast milk are urged to avoid breast-feeding to decrease the risk of transmission.
Advances in managing HIV disease have offered many benefits in maternal and child health, most notably in terms of the reduction in rates of vertical transmission. Yet, anti-HIV therapy is only one part of a vertical transmission prevention strategy. Regardless of a woman's decision around the use of anti-HIV therapy, good prenatal care and addressing surrounding health issues are key to a prevention strategy. Such a comprehensive care strategy will no doubt translate into a healthier pregnancy, decreased transmission rate and a healthier mother and child.
For more information on this topic, call Project Inform's National HIV/AIDS Treatment Hotline and request the Mother-to-Child HIV Transmission Prevention Discussion Paper.
For victims of domestic violence, call the National Domestic Violence Hotline: 800-799-SAFE (7233).