The Period Pills Study is a prospective observational study among people who decide to use a combination of mifepristone and misoprostol for menstrual regulation.

Period pills (a combination of mifepristone and misoprostol) for people who suspect, but have not confirmed pregnancy, has the potential to fulfill this growing need. In the United States (U.S.), a handful of providers currently offer period pills alongside other contraceptive and abortion services in their practice (https://www.periodpills.org/providers). This proposed study would aim to assess the acceptability of this growing service as a fertility regulation method to be utilized before a person confirms they are pregnant.

Dr. Ushma Upadhyay (Professor) and Dr. Tania Serna (Associate Clinical Professor) at UCSF's Department of Obstetrics, Gynecology & Reproductive Science are proposing the Period Pills Study to test a traditional but underutilized framework of menstrual regulation for pregnancy loss, to "bring back" a period when it is late, or missed. This study will aim to recruit 100 participants who have a late period to address research questions that focus on the feasibility and acceptability of using period pills for menstrual regulation.

Inclusion Criteria:

• Be 18 years old or older
• Read and speak English
• Know the date of their last menstrual period within 2 days
• Have a period that is late by up to 21 days
• Must have had regular periods in the last 4 months
• Does not want to be pregnant
• Does not want to verify pregnancy status
• Understand that if they are pregnant, the pills will end their pregnancy
• Does not have contraindications to mifepristone and misoprostol (Risk factors for ectopic pregnancy; history of bleeding disorder or anticoagulant therapy; history of chronic adrenal failure, long-term corticosteroid therapy; allergy to mifepristone/misoprostol/prostaglandins; history of hemorrhagic disorders or anticoagulant therapy; history of inherited porphyrias; has an IUD; currently use a contraceptive implant or injectable)

Exclusion Criteria:

• Under 18 years old
• Does not read and speak English
• Does not know the date of their last menstrual period within 2 days
• Has not had regular periods in the last 4 months
• Wants to be pregnant
• Wants to verify pregnancy status
• Does not display understanding that if they are pregnant, the pills will end their pregnancy
• Has any contraindications to mifepristone and misoprostol (Risk factors for ectopic pregnancy; history of bleeding disorder or anticoagulant therapy; history of chronic adrenal failure, long-term corticosteroid therapy; allergy to mifepristone/misoprostol/prostaglandins; history of hemorrhagic disorders or anticoagulant therapy; history of inherited porphyrias; has an IUD; currently use a contraceptive implant or injectable)