Disclosure of HIV status is widely promoted in the prevention of mother-to-child transmission (PMTCT), but a number of context-specific factors may mediate disclosure outcomes. To better understand HIV-disclosure dynamics, we conducted in-depth interviews among 62 HIV-positive pregnant women accessing PMTCT services in Durban, South Africa. Transcripts were coded for emergent themes and categories. Thirty-nine women (63 %) had been recently diagnosed with HIV; most (n = 37; 95 %) were diagnosed following routine antenatal HIV testing. Forty-two women (68 %) reported unplanned pregnancies. Overall, 37 women (60 %) reported an unintended pregnancy and recent HIV diagnosis. For them, 2 life-changing diagnoses had resulted in a double-disclosure bind. The timing and stigma surrounding these events strongly influenced disclosure of pregnancy and/or HIV. PMTCT-related counseling must be responsive to the complex personal implications of contemporaneous, life-changing events, especially their effect on HIV-disclosure dynamics and, ultimately, on achieving better maternal mental-health outcomes.