This is a prospective cohort study. We will identify women who present to Planned Parenthood League of Massachusetts (PPLM) with pregnancy of unknown location (PUL) who desire medication abortion. For the purposes of this study, PUL will be defined as no intrauterine gestational sac visualized on ultrasound. Women with PUL who are eligible for immediate initiation of mifepristone with close follow-up according to PPLM clinical protocol will be invited to participate. Once enrolled, participants will be allowed to choose their desired method, and will be followed prospectively according to PPLM clinical protocol.
The specific aim of this study is to determine time to completed abortion, defined as number of days between initial ultrasound diagnosis of PUL to the diagnostic test that confirms complete abortion. We will describe differences in time to completed abortion between patients with same-day start and those with delay-for-diagnosis. We hypothesize that same-day medication abortion will result in a shorter time to completed abortion.
Secondary outcomes will include time to diagnosis, adherence to recommended follow-up, efficacy, utilization of resources (i.e. number of visits, staff phone calls, serum hCG tests and ultrasounds) obtained throughout a participant’s clinical course, the occurrence of ectopic pregnancy, and percentage of negative urine pregnancy tests 14 days post-mifepristone administration. Additionally, we will describe patient and provider satisfaction as well as sociodemographics including insurance status and distance travelled to obtain abortion.
Our study population will be those women presenting to PPLM between July 1, 2019 and October 31, 2020.

Using a two-sided alpha of 0.05 and an estimated 20% loss to follow-up we will need a sample size of 28 to achieve 98.8% power given a presumed 3:1 allocation to groups. We aim to enroll at least 10 per arm (total N=31) in order to better evaluate secondary outcomes.