The goal of this study is to learn if genetic differences may impact the risk of emergency contraceptive failure. 

You may qualify if you meet the following criteria.

Inclusion Criteria:

• Ages 18-40
• Have normal menstrual cycles (21-35 days)
• Not used hormonal birth control in past 8 weeks
• Not pregnant or seeking pregnancy in the next 3 months
• Willing to use non-hormonal contraception, like condoms, during the study
• Do not smoke
• No metabolic disorder diagnosis (e.g., diabetes, polycystic ovarian syndrome, uncontrolled thyroid disorder)
• Not sensitive to or allergic to contraceptive pill Ella or oral birth control pills
• Not been treated for infertility
• Do not routinely use nonsteroidal anti-inflammatory drugs (e.g. aspirin, ibuprofen)
• No expected travel in the next 3 months

During this 2-month study, participants will attend 15 study visits, and will receive the following procedures and measurements:

• Vital signs (blood pressure and pulse, height and weight)
• Blood draw at each visit (including a longer series of blood draws on the day study medication is taken)
• I.V. (intravenous access) placement. You may also choose “single stick” venipuncture for each blood draw
• Transvaginal ultrasound scan (TVUS)

The medication used in this study is an FDA-approved emergency contraceptive pill containing ulipristal acetate (UPA, otherwise known as Ella ©).

Most visits will last approximately 30 minutes, with the exception of the initial screening visit, which will last approximately 90 minutes. If you participate in the PK substudy, one study visit will last approximately 5 hours and will include a longer series of blood draws.

As a participant, you can receive up to $885 for your time and effort.

There is no cost for you to participate in our research study.