Gender Differences in Perinatal HIV Acquisition Among African Infants

Abstract

ABSTRACT. Objective. We investigated gender-specific risks of mother-to-child transmission (MTCT) at birth and at 6 to 8 weeks among infants born to HIVinfected African women.Design. Follow-up study of infants enrolled in 2 randomized, phase III, clinical trials to prevent MTCT, conducted in Blantyre, Malawi, in southeast Africa.Methods. Infants were enrolled at birth and monitored postnatally, and their HIV status was assessed at birth and at 6 to 8 weeks (assessment beyond 6 -8 weeks is ongoing). Statistical analyses were stratified according to gender, and comparisons were made with descriptive, univariate, and multivariate statistical tests. MTCT was estimated at birth and at 6 to 8 weeks among infants who were not infected at birth.Results. Overall, 966 boys and 998 girls were enrolled. The rate of HIV transmission at birth was 9.5% (187 of 1964 infants). However, at birth significantly more girls (12.6%) than boys (6.3%) were infected with HIV. This association remained significant after controlling for maternal viral load and other factors. Among infants who were uninfected at birth, 8.7% (135 of 1554 infants) acquired HIV by 6 to 8 weeks; of these infants, more girls acquired HIV (10.0%), compared with boys (7.4%).Conclusions. Female infants may be more susceptible to HIV infection before birth and continuing after birth. Alternatively, in utero mortality rates of HIV-infected male infants may be disproportionately higher and thus more HIV-infected female infants are born. In areas of sub-Saharan Africa, where HIV infection rates are high among women of reproductive age, the magnitude of the gender transmission differences observed in this study could have clinical, preventive, and demographic implications. Pediatrics 2005;115:e167-e172. URL: www. pediatrics.org/cgi/doi/10.1542/peds.2004-1590; acquisition, Africa, gender, HIV, mother-to-child transmission, susceptibility.ABBREVIATIONS. MTCT, mother-to-child transmission; CI, confidence interval; NVP, nevirapine; ZDV, zidovudine. I n developing countries, the risk of mother-tochild transmission (MTCT) of HIV is ϳ15 to 40% 1 but varies with antiretroviral treatment and breastfeeding. MTCT of HIV can occur in utero (20 -25%), intrapartum (65-70%), or postnatally (10 -15%). 2 As with other infectious diseases, the probability of HIV transmission is dependent on the infectiousness of the index case, the mode of spread, and the susceptibility of exposed individuals. 3,4 For MTCT of HIV, infectiousness is determined by maternal viral load, a risk factor strongly associated with perinatal infection 5-7 and the potential for HIV transmission through the in utero, intrapartum, and postpartum routes. Susceptibility, however, may be determined by genetic factors and/or acquired resistance. 8 Among adults, gender differences in heterosexual HIV infection rates have been attributed to various biological (immunologic, genetic, viral, and hormonal), social, and behavioral factors. 9-15 Among children, gender-specific differences could indicate inherent physiologic facto...

To Say or Not to Say: A Qualitative Study on the Disclosure of Their Condition by Human Immunodeficiency Virus–Positive Adolescents

“…First, it contains more girls than boys, a characteristic that also applies to the entire sample of adolescents within the Swiss MoCHiV cohort. We do not know to what extent this may be due to a higher chance that girls contract HIV infection through vertical transmission, as suggested in a few publications [15,16]. Another characteristic of this sample is that only one of the 29 subjects lived with two biological parents.…”

Age and gender specific prevalence of HTLV-1

“…For female donors overall, the older age subgroups had significantly higher HTLV-1 seroprevalence compared with younger subgroups in all pair-wise comparisons (p < 0.0001) except between G [16][17][18][19] and G [20][21][22][23][24][25][26][27][28][29] (Table 1). This trend was also observed for male donors, where G [16][17][18][19] and G 20-29 were not significantly different and all other pair-wise comparisons showed significantly higher seroprevalence for older subgroups (p = 0.0087 between G 20-29 and G 30-39 , and p < 0.0001 for all other pair-wise comparisons, Table 1).…”

“…However, a study conducted on ∼1800 infants born to HCV-infected mothers demonstrated twice as much vertical transmission to females as males. 23 For HIV, intra-uterine infection is reported to be female dominant, [24][25][26][27][28] whereas post-natal infection is more common for males. 29,30 One might speculate that the gender-specific risk of transmission varies according to the transmission route.…”

Children With Cancer and HIV Infection

“…21 However, this ratio is significantly higher in the children with cancer and HIV, at 2.1:1. Considering the published evidence for a 2:1 ratio of vertical transmission of HIV to female fetuses versus males, 22 this imbalance seems even larger. This confirms the overrepresentation of males in childhood cancers with HIV, which was signaled by others too.…”