Postpartum
Postpartum interventions to prevent vertical transmission of HIV include protecting the health of the mother with ARV treatment and providing ARV prophylaxis to the mother and/or the baby to reduce HIV transmission via breastfeeding. Contraception counseling for women in order to space their next pregnancy or prevent an unintended pregnancy is also a critical – though often overlooked – component of postpartum intervention planning in PMTCT for HIV-positive women (Wilcher et al. 2008).
The benefits of ARV treatment for women living with HIV have been previously discussed. ARV treatment for infants and children can also provide excellent prospects for survival into adulthood. However, without antiretroviral treatment, approximately half of children with perinatal infection die before two years of age (Newell et al., 2004, cited in Abrams, 2007). “International approaches for preventing MTCT of HIV now focus on child survival, not just HIV transmission, as the appropriate outcome to measure success of PMTCT programs. Ultimately, the goal is a live and healthy, HIV-negative child and an alive and healthy mother to care for that child” (Jackson et al., 2009: 226).
Four Interventions to Reduce Postnatal Transmission
What works best to prevent postnatal transmission via breastfeeding has been the subject of much scrutiny. A 2009 Cochrane review, based on six randomized control trials and one intervention cohort study (data from 1980-2008) found four interventions effective in reducing postnatal HIV transmission. These interventions included: 1) decreasing the duration of breastfeeding through complete avoidance or early cessation; 2) lowering maternal viral load in breast milk through the use of maternal antiretrovirals or treating breast milk with heat or chemicals to deactivate the HIV virus; 3) providing mothers with adequate education and counseling so that they understand how to breastfeed properly and the importance of exclusive breastfeeding when exclusive replacement feeding is not feasible, and how to treat breast abnormalities such as mastitis (which increases the risk of transmission); and 4) improving infant’s defense against HIV transmission through extended antiretroviral prophylaxis during breastfeeding (Horvath et al., 2009). “Identified risk factors for transmission during breastfeeding include increased severity of maternal disease, mastitis and breast abscess, mixed infant feeding, maternal seroconversion during lactation, lower maternal CD4 cell count, and higher maternal HIV viral load” (Mmiro et al, 2009: 32).
Formula Feeding May Increase Infant Mortality Where There is No Access To Clean Water
Infant formula feeding may avert transmission of HIV via breastfeeding. However, there are more than one billion people globally without adequate access to clean water, leading to over 1.8 million child deaths from diarrhea and other diseases caused by unclean water and poor sanitation. In settings prevalent in most of the developing world where there is no access to safe, clean drinking water, HIV-positive women who use infant formula may see their baby, who was born HIV-negative, die from diarrheal diseases if fed formula. “Several studies confirm that the benefits of shortening breastfeeding are offset by adverse outcomes in those infants who escape infection” (Kuhn et al., 2009a: 83). Globally, breastfeeding leads to about 300,000 HIV-positive infants every year, while at the same time, UNICEF estimates that not breastfeeding and having infants formula fed with contaminated water leads to approximately one and a half million child deaths per year (Fletcher et al., 2008). Additionally, concerns have been raised that promoting infant formula as a best practice to prevent vertical transmission may have negative consequences by decreasing breastfeeding of infants.
For women who do not have access to ARVs for either treatment or MTCT prophylaxis and who do not have access to clean water to make formula feeding safe, health providers have been advising breastfeeding. Many studies have shown that mixed feeding increases the risk of HIV transmission from the HIV-positive mother to her infant. Experts thus advise that it is better for an HIV-positive mother to exclusively breastfeed than to breastfeed and add any additional nutrition in the way of food or water prior to six months (Kuhn et al., 2009a). After six months, for HIV-positive mothers who do not have access to clean water, infant survival is increased by continued breastfeeding and adding additional nutrients for the child. Breastfeeding beyond six months, however, may increase the risk of HIV infection of the infant to 9.68% by the time the infant is two years old (Taha et al., 2007). Experts advise that infants who are HIV-positive should be breastfed. However, in most cases, the choice of feeding is often decided before the mother knows her infant’s serostatus.
“There is no doubt that there are small groups in resource-constrained countries with basic and essential services that allow the hygienic preparation of formula milks. However, for the child population as a whole, the unrestrained promotion of formula is generally harmful…exclusive breastfeeding, which is threatened by the HIV epidemic, remains an unfailing anchor of child survival” (Coutsoudis et al., 2008: 210). Feeding choices can be laden with stigma as well. HIV-positive women may face heavy stigma from partners, families and communities if they formula feed their infants, yet if they do not formula feed, they may fear HIV transmission to their infants.
New Guidelines About Infant Feeding Still Leave Unanswered Questions
The WHO rolled out a new policy on infant feeding in November 2009 (WHO, 2009a: http://whqlibdoc.who.int/publications/2009/9789241598873_eng.pdf), which elaborates on an earlier WHO policy for infant formula to be used for HIV-positive women when it is “affordable, feasible, acceptable, safe and sustainable” (WHO, 2006a). The newly issued recommendations from WHO now recommend that “mothers known to be HIV-infected (and whose infants are HIV-uninfected or of unknown HIV status) should exclusively breastfeed their infants for the first six months of life, introducing appropriate complimentary foods thereafter, and continue breastfeeding for the first 12 months of life. Breastfeeding should then only stop once a nutritionally adequate and safe diet without breastfeeding can be provided” (WHO, 2009a: 15). HIV-positive women should also know that breastfeeding does not harm their own health (Taha et al., 2006, Allen et al., 2007a, Lockman et al., 2009, Wilfert and Fowler, 2007). The November 2009 WHO guidelines state that if infant formula is given to prevent perinatal transmission, the following conditions are needed: safe water and sanitation assured at the household level and in the community; the mother or other caregiver can reliably provide sufficient infant formula milk to support normal growth and development of the infant; the mother or caregiver can prepare it cleanly and frequently enough so that it is safe and carries a low risk of diarrhea and malnutrition; the mother can, in the first six months, exclusively give infant formula milk; and the family is supportive of this practice; and the mother or caregiver can access health care that offers comprehensive child health services (WHO, 2009b: 19).
The WHO also recommends that if mothers are started late in pregnancy on ART, or have not achieved full viral suppression, that infants be given daily AZT or NVP from birth until six weeks of age (WHO, 2009b). However, the impact on future treatment options should an infant become HIV-positive while on this regimen are unclear. Studies show that infant prophylaxis can decrease breast milk transmission. However, “…it is difficult to translate these research findings into policy for resource-limited countries. No consensus has been reached yet about the duration of prophylaxis and the antiretroviral drugs to use” (Mnyani and McIntyre, 2009: 73).
Infant Feeding Research Offers Complex and Contradictory Advice
In the absence of HAART or safe conditions for infant feeding, questions remain on how long HIV-positive women should breastfeed to minimize the risk of HIV transmission but reduce the risk of their infant dying from diarrheal disease.
While WHO recommends breastfeeding to avert infant deaths due to diarrheal disease, breastfeeding beyond six months increases the risk of HIV transmission to the infant. One study analyzed the results of a clinical trial from 2001-2003 in Malawi, Tanzania and Zambia that followed infants born to HIV-positive mothers over 12 months and found that of 1,979 infants, 404 (20.4%) acquired HIV. Breastfeeding longer than six months increased risk of HIV acquisition by infants. Late postnatal transmission was associated with lower CD4 cell count and higher viral load at baseline. The analysis used data from the HIV Prevention Trials Network Protocol, which was a randomized controlled trial. The trial provided counseling on breastfeeding only with no information related to replacement feeding or other alternative and all women received nevirapine (Chasela et al., 2008).
Infant feeding studies offer complex and sometimes contradictory advice on the best feeding practices and the optimal time to wean for both averting HIV transmission and reducing infant mortality (Palombi et al., 2007; Kagaayi et al., 2008; Kuhn et al., 2009c; Kuhn et al., 2010; Taha et al., 2007; Becquet et al., 2008; Sarr et al., 2008; Kuhn et al., 2008; Thior et al., 2006; Leroy et al., 2008 cited in Gray and Saloojee, 2008; Becquet et al., 2007; Rollins et al., 2008). However, it is clear that for women who lack access to ARVs, the CD4 count is important in the likelihood of HIV transmission to the infant (Kuhn et al., 2009c, Kuhn et al., 2010). Ultimately, HAART for the mothers improves the likelihood that infants will not acquire HIV via breastfeeding (Kuhn et al., 2009c).
Studies show that mixed feeding (when a mother both breastfeeds and provides any other food, in addition to breast milk), particularly prior to the infant being four to six months of age, can put the infant at a higher risk of acquiring HIV. Studies describe the increased statistical risk of the infant acquiring HIV when mixed feeding is used, but do not describe the mechanism. It may be that the immature gut mucosa in an infant can be damaged by the introduction of other foods and nonhuman milk, thus leading to increased permeability enabling HIV viral entry (Charurat et al., 2009) or it may be that when a mother does not breastfeed regularly she can develop mastitis, a painful inflammation of the breast. Mastitis may not always be severe enough to compel a woman to receive medical care, however, studies have shown that HIV-positive women with even subclinical cases of mastitis have a higher viral load in the breast milk of the affected breast (Nussenblatt et al., 2006, Kasonka et al., 2006, Kantarci et al., 2007). Further research is needed.
“While the international guidelines of exclusive breastfeeding for a six month period seem to offer the least worst strategy for reducing mother-to-child transmission of HIV during infancy, while conferring some immunity through breastfeeding post six months….[this] translates into a complicated painful moral dilemma for HIV-positive mothers….” (Fletcher et al., 2008: 307). How to reduce transmission postnatally remains challenging, as HIV transmission can occur during breastfeeding by a woman living with HIV to the infant, but infant formula feeding increases the risk of the infant dying of diarrheal disease. Women living with HIV also face pressures from their partners, families and communities to breastfeed. In many countries, formula feeding is associated with HIV and women who formula feed face stigma. For example, in Botswana, free ARVs and infant formula are widely available, as is safe drinking water; yet, more than half of women in a study did not formula feed their babies due to stigma (Shapiro et al., 2003). PMTCT programs may also inadvertently increase stigma against women living with HIV by having separate HIV facilities, home visits for HIV-positive women, or providing infant formula (Thorsen et al., 2008). For women living with HIV who have infants who are HIV-positive, breastfeeding is best, but women are often unable to know their infant’s serostatus prior to deciding whether to breastfeed or not.
Further research is urgently needed to clarify what works best in infant feeding to prevent perinatal transmission. “Prevention of mother-to-child HIV transmission during breastfeeding remains one of the greatest challenges facing scientists, clinicians and women in the developing world… While awaiting further studies… promoting exclusive breastfeeding with safer weaning and assuring ART for pregnant and postpartum women with advanced HIV will likely prevent the majority of needless maternal and infant deaths” (Kuhn et al., 2009a: 90-91).