We investigated factors associated with unintended index pregnancy, unmet contraceptive need, future pregnancy intention and current contraceptive use among Malawian women living with HIV in the Option B+ era. Women who tested HIV positive at 4–26 weeks postpartum were enrolled into a cross-sectional study at high-volume under-5 clinics. We enrolled 578 HIV-positive women between May 2015-May 2016; median maternal age was 28 years (y), median parity was 3 deliveries, and median infant age was 7 weeks. Overall, 41.8% women reported unintended index pregnancy, of whom 35.0% reported unmet contraceptive need and 65.0% contraceptive failure. High prevalence of unintended index pregnancy and unmet contraceptive need among HIV-positive women highlight the need for improved access to contraceptives. To help achieve reproductive goals and elimination of MTCT of HIV, integration of family planning into HIV care should be strengthened to ensure women have timely access to a wide range of family planning methods with low failure risk.