The routine antenatal screening through the prevention of mother to child transmission of HIV (PMTCT) services results in pregnancy being often the point at which an HIV diagnosis is made. Disclosure to partners presents particular complexities during pregnancy. However, research on the pattern and experiences of disclosure in pregnancy is limited in Lesotho, despite the high prevalence of HIV among pregnant women. The aim of this study was to explore and describe the disclosure experiences of adolescent girls and young women (AGYW) after receiving a positive HIV test result during pregnancy. Methods. Descriptive phenomenology using semistructured in-depth interview was used to collect data from AGYM sampled purposively from PMTCT sites located in urban areas of Maseru, Lesotho. Data analysis was inductive and followed the thematic approach. Findings. There were 15 AGYW involved in this study with the mean age of 20 years. Fourteen reported being pregnant with their first child and perceived HIV testing in antenatal care as compulsory. Ten AGYM disclosed their HIV status in the immediate posttesting period to protect their partners from HIV infection. The narratives revealed that the AGYM hoped that after disclosing, the partner would be tested for HIV. Furthermore, the AGYM disclosed because they wanted freedom to take their medication. Their experience of disclosure was relief, as they did not have to hide their HIV status. The AGYM reported being supported to adhere to medication and clinic attendance by their partners who also provided emotional support to them to deal with being HIV positive and pregnant. Conclusion. The AGYM recounted an overall positive experience of disclosure to their partners who agreed to test for HIV and adopted safe sex practices. This has positive implications for the PMTCT programme and the involvement of men in reproductive health. Therefore, there is need to integrate disclosure and partner testing interventions in the cascade of services in PMTCT programmes.