The use of Mifepristone, an antiprogesterone, and Misoprostol together, has been shown to make the medial abortion process more efficient and reduce the induction-to-abortion interval by almost 50%. Despite the recommended 24-48 Mifepristone-Misoprostol interval, recent retrospective study of a flexible interval, have revealed shorter total abortion time with shorter intervals. In this study we aim to compare 24 to 12 hours Mifepristone to Misoprostol intervals

Women are looking for termination of pregnancies in the second trimester, after 12 weeks of gestation for social and medical reasons, as well as due to intrauterine fetal demise. Both surgical and medical methods can be used, depending on the patients' preference, providers skills, availability of drugs and instruments and more. Methods of medical abortion can be performed with the use of prostaglandin analogues, mifepristone, oxytocin, foley catheter and osmotic dilators. Misoprostol, a prostaglandin analogue (PGE1), is currently recommended over other agents due to its efficacy, low cost and ease of use. Misoprostol can be used alone or in combination with other agents. The use of Mifepristone, an antiprogesterone, and Misoprostol together, has been shown to make the medial abortion process more efficient and reduce the induction-to-abortion interval by almost 50%. Current guidelines recommend the use of Mifepristone 200 mg orally, followed by Misoprostol 400 mcg every 3-4, hours 24-48 later until expulsion of the fetus. Despite the recommended 24-48 Mifepristone-Misoprostol interval, recent retrospective study of a flexible interval, ≤12, 12-24 and >24 hours, have revealed shorter total abortion time (time from Mifepristone to fetal expulsion) with the shorter intervals. Thus, strict adherence to current guidelines may unnecessarily prolong the abortion procedure.

Objective Prompted by the need to explore more beneficial methods and regimes for second trimester medical abortion, we aim to compare 24 to 12 hours Mifepristone to Misoprostol intervals

Material and Methods Women eligible for second trimester medical abortion will be approached to enroll in the study at the clinic or emergency room when they arrive to schedule medical abortion. A research staff member will obtain informed consent. The patient will undergo a blood test including blood type, complete blood count and chemistry. Basic demographic information will be collected. A complete history and physical assessment will be performed. If an ultrasound report is not available to confirm gestational age dating, ultrasound will be performed to determine gestational age. A baseline cervical exam will be done at this visit to assess cervical consistency. Patients will be randomized into one of two groups according to a computer-generated random allocation sequence. Sequentially numbered sealed opaque envelopes will be used to provide allocation.

• Patients allocated to group 1 will receive 200 mg Mifepristone orally, followed by Misoprostol 400 mcg vaginally 12 hours later and subsequently 400 mcg orally every three hours until fetal expulsion to a maximum of 5 doses.
• Patients allocated to group 2 will receive 200 mg Mifepristone orally, followed by Misoprostol 400 mcg vaginally 24 hours later and subsequently 400 mcg orally every three hours until fetal expulsion to a maximum of 5 doses.

Patients will be discharged home after receiving Mifepristone, and hospitalized upon arrival for the Misoprostol administration.

If the abortion is not complete after five doses, the woman may be allowed to rest for 12 hours before starting the cycle again.

All participants will be contacted by phone as well as a chart review conducted to assess for delayed complications. During this follow up time, they will be asked to notify the research team if they should develop fatigue, malaise, abdominal pain, or jaundice. If these symptoms occur, a workup for liver injury would be performed. Patients will be asked to obtain repeat liver function tests within two weeks post-procedure to compare to their baseline hepatic panel.

Inclusion Criteria:

• Women aged 18 years and older about to undergo medical second trimester abortion
• 12+0 to 28+0 weeks of gestation
• Singleton intrauterine pregnancy
• Able to sign informed consent

Exclusion Criteria:

• Inability to give informed consent

• Allergy to any of the drugs used in the study

• Genital bleeding of unknown etiology; cancer of the breast, cervix, uterus, or ovaries; hepatic disease (current or history of)

• Multiple gestation

• Rupture of membranes

• Taken a CYP3A4 inhibitor within 5 elimination half-lives of the drug from the procedure

• Pre-dosing abnormal liver function tests

• Patients at increased risk of hepatitis based on a history of any of the following:

  • Any history of underlying liver disorder, including hepatitis
  • A family history of hepatitis or currently living with a person 441 who has been given a diagnosis of hepatitis
  • A history of or currently working as a sex worker
  • A history of or currently using IV drugs
  • A self-reported history of alcoholic dependency or abuse

Female