biostudies-literatureUpadhyay UDNICHD NIH HHSNIMHD NIH HHSU.S. Department of Health & Human Services | NIH | National Institute on Minority Health and Health DisparitiesThe BaSe Family Fund, Erik E. and Edith H. Bergstrom Foundation, Isabel Allende Foundation, Jess Jacobs, Kahle/Austin Foundation, Lisa and Douglas Goldman Fund, and Preston-Werner Ventures.Resource Allocation Program (RAP) Award from the UCSF National Center of Excellence in Women’s Health1191-1198https://www.ebi.ac.uk/biostudies/studies/S-EPMC11031403biostudies-literatureUnknown30(4)Telehealth abortion has become critical to addressing surges in demand in states where abortion remains legal but evidence on its effectiveness and safety is limited. California Home Abortion by Telehealth (CHAT) is a prospective study that follows pregnant people who obtained medication abortion via telehealth from three virtual clinics operating in 20 states and Washington, DC between April 2021 and January 2022. Individuals were screened using a standardized no-test protocol, primarily relying on their medical history to assess medical eligibility. We assessed effectiveness, defined as complete abortion after 200 mg mifepristone and 1,600 μg misoprostol (or lower) without additional intervention; safety was measured by the absence of serious adverse events. We estimated rates using multNature medicineEffectiveness and safety of telehealth medication abortion in the USA.PMC11031403F31 HD111277T32 MD015070T32MD015070Meckstroth KValladares ESBiggs MAKoenig LRUpadhyay UDKo JfalseEffectiveness and safety of telehealth medication abortion in the USA.Telehealth abortion has become critical to addressing surges in demand in states where abortion remains legal but evidence on its effectiveness and safety is limited. California Home Abortion by Telehealth (CHAT) is a prospective study that follows pregnant people who obtained medication abortion via telehealth from three virtual clinics operating in 20 states and Washington, DC between April 2021 and January 2022. Individuals were screened using a standardized no-test protocol, primarily relying on their medical history to assess medical eligibility. We assessed effectiveness, defined as complete abortion after 200 mg mifepristone and 1,600 μg misoprostol (or lower) without additional intervention; safety was measured by the absence of serious adverse events. We estimated rates using mult2024-01-01T00:00:00Z2024 Apr2026-06-01T21:20:01.224Z2025-04-04T21:22:07.482ZS-EPMC110314033836112310.1038/s41591-024-02834-w