Same-day Dilapan-S With Adjunctive Misoprostol

Cervical preparation before second trimester dilation and evacuation (D\&E) reduces risks and complications. Osmotic cervical dilators as well as prostaglandin analogues have been studied for cervical preparation. However, the optimal method for cervical preparation, especially for D\&E procedures that occur on the same day as cervical preparation, is not known. This study will investigate misoprostol versus placebo as an adjunct to Dilapan-S for cervical preparation for same-day D\&E between 16+0 and 20+6 weeks gestation.

HYPOTHESIS: Administration of 400 µg buccal misoprostol compared to placebo at least 3 hours prior to D\&E as an adjunct to cervical preparation with Dilapan-S will decrease operative time for same-day D\&E performed between 16+0 and 20+6 weeks.

Dilation and evacuation (D\&E) is commonly performed for second trimester abortions and management of second trimester intrauterine fetal demise (IUFD). Cervical preparation prior to second trimester D\&E increases safety.

Osmotic cervical dilators and prostaglandin analogs are used widely for cervical preparation before second trimester D\&E. Osmotic dilators are placed into the cervical canal, radially expand as they absorb moisture and decrease the risk of cervical injury during D\&E. Laminaria tents are the most commonly used osmotic dilator for D\&E cervical preparation but require N18 h to reach maximum diameter. Dilapan-S®, a synthetic osmotic cervical dilator, has a significant dilation effect 2 h after placement with the majority of expansion occurring in 4-6 h according to the manufacturer.

Misoprostol is the most commonly used pharmacologic cervical preparation for D\&E with duration of action between 2 and 4 h after administration. Multiple studies demonstrate the safety of misoprostol before early second trimester abortion. One prospective and four retrospective studies suggest that same-day cervical preparation with Dilapan-S and/or misoprostol for second trimester D\&E through 20 weeks is safe and effective. Misoprostol may be less effective when used alone compared to overnight osmotic dilators for cervical preparation later in the second trimester but has adjunctive benefit on cervical dilation and procedure time when used with overnight osmotic dilators between 16 and 24 weeks. The effect appears most pronounced at N19 weeks gestation. No prospective studies have been published examining misoprostol as an adjunct to osmotic dilators for cervical preparation for same-day D\&E.

Administration of adjunctive misoprostol with Dilapan-S has the potential to effectively prepare the cervix and decrease operative time for same-day D\&E. We compared cervical preparation with Dilapan-S with and without adjunctive buccal misoprostol for same-day D\&E between 16 0/7 and 20 6/7 weeks gestation.

Eligibility Criteria:
Inclusion Criteria:

* Age greater than or equal to 18 years (no upper age limit)
* Gestational age between 16+0 and 20+6 weeks gestation on day of D\&E with confirmation of gestational age by ultrasound
* Desires D\&E for termination of pregnancy or for fetal demise
* Able to provide written informed consent
* Able to comply with study procedures
* English-speaking

Exclusion Criteria:

* Known allergy or contraindication to misoprostol
* Pregnancy with a multiple gestation
* Known bleeding disorder or current anticoagulation therapy (within one month of procedure)
* Active bleeding or hemodynamically unstable at enrollment
* Signs of chorioamnionitis or clinical infection at enrollment
* Signs of spontaneous labor or cervical insufficiency at enrollment