Many countries in sub-Saharan Africa are in the process of integrating antenatal voluntary HIV-1 counseling and testing (VCT), antiretroviral prophylaxis, and counseling regarding infant feeding into routine maternal and child health services.1 Even with greater availability of interventions to protect infants from HIV-1 acquisition, many women choose not to receive their HIV-1 test results, and many who learn that they are HIV infected do not implement interventions to prevent vertical or sexual transmission. In both research and non-research settings, <75% of HIV-infected pregnant women who are tested learn their HIV-1 status2,3 and <50% of these women obtain antiretrovirals to prevent mother-to-child HIV-1 transmission2,4–6 or use condoms postpartum.7,8 Not disclosing HIV-1 test results to a sexual partner may impede a woman’s access to interventions to prevent vertical and sexual HIV-1 transmission. There is evidence that lack of partner support is associated with poor uptake of antiretroviral medication and the inability to modify infant feeding practices.9,10 Sexual abstinence and condom use have also been shown to be more common among postpartum women who reveal HIV-positive results to partners.7 These associations between partner involvement and uptake of interventions underscore the importance of involving the male partner in HIV-1 prevention efforts initiated in the antenatal setting. Antenatal VCT involves counseling and testing the woman alone, with the expectation that she will disclose results to her partner. Using this model, the majority of pregnant women in stable relationships who are tested as part of routine care do not inform their partner of positive HIV-1 results, fearing domestic violence, abandonment, or stigmatization.7,11,12 We hypothesized that conducting VCT for pregnant women together with partners could facilitate notification and increase partner participation in the decision-making process. This could in turn improve maternal access to mother-to-child HIV-1 prevention interventions. Studies among discordant couples in nonantenatal settings support this hypothesis and demonstrate that couple counseling is associated with significant behavior change, including sustainable increases in condom use.13–15 In addition, when comparing couple counseling and individual counseling, provision of counseling to couples appears to be more cost-effective in averting HIV-1 infections.16 To examine whether couple counseling in the antenatal setting could be used as a strategy to increase use of interventions to prevent perinatal and sexual HIV-1 transmission, we introduced couple VCT into a Nairobi antenatal clinic and determined the prevalence and correlates of partner participation and couple counseling. The study’s primary aim was to assess the impact of partner involvement, specifically being counseled as a couple, on perinatal intervention uptake and condom use.