Mifepristone vs Misoprostol

Cervical preparation is a critical component for the provision of safe abortion care in the later first trimester and beyond. The risk of surgical complications increases at 12 to 13 weeks gestation and routine use of cervical preparation is recommended. Cervical preparation options include misoprostol, mifepristone, and cervical dilators. Regimen choice is often guided by provider comfort, preference, or institutional guidelines. Misoprostol offers the advantage of facilitating same-day procedures, but side effects like pain and gastrointestinal symptoms can negatively affect patients' experiences. Furthermore, using misoprostol can pose logistical challenges in hospital-based main operating room environments, where abortions occur concurrently with all other surgical cases. Mifepristone is better tolerated than misoprostol but requires a multiple-day protocol for administration, which can pose logistical challenges.

Several studies demonstrate mifepristone's efficacy and safety as a cervical ripening agent for up to 16 weeks' gestation, however, despite its effectiveness, mifepristone for cervical preparation before procedural abortion has previously been limited by availability and cost. Recent studies demonstrating mifepristone's adjunctive benefit with osmotic dilators later in pregnancy, however, have broadened its use.

While most abortion care in the United States occurs in outpatient settings, about 3% occur in hospitals. This is expected to increase as the Dobbs versus Jackson Women's Health Organization decision exacerbates disparities in abortion access. In hospital-based abortion care, particularly at academic centers providing abortion training, there is a pressing need for innovative measures for cervical ripening. The Complex Family Planning Fellowship-trained faculty members at Montefiore will serve as research study surgeons. Cases will be performed in the main operating room under sedation or general anesthesia as determined by the anesthesiologist. A paracervical block of 20cc 1% lidocaine, with or without vasopressin, will be administered in accordance with standard practices.

Inclusion criteria

• English or Spanish-speaking
• Capacity to consent
• Seeking induced abortion of a singleton pregnancy between 12 weeks, 0 days and 16 weeks, 6 days (based on age at day of surgery)

Exclusion criteria

• History of more than two prior Cesarean deliveries
• Sonographic evidence of placenta previa
• Sonographic concern for morbidly adherent placenta
• Prior obstetric hemorrhage requiring transfusion
• Obstructive cervical or lower uterine segment fibroid
• Current therapeutic anticoagulation use
• Cerclage in situ
• History of more than one prior cervical excisional procedure
• BMI greater than 50 kg/m^2