Gabapentin for Pain Control After Osmotic Dilator Insertion and Prior to D&E Procedure: a Randomized Controlled Trial

Women having abortion procedures between 15 weeks 0 days and 23 weeks 6 days gestational age on the day of their procedure commonly have dilators placed in their cervix overnight before the abortion procedure. The dilators are put in during a pelvic exam in the clinic and after women go home they expand slowly overnight to open the cervix before the abortion procedure the next day. This can be a painful experience and health care providers often give women different kinds of pain medicine to help them.

The investigators are interested in whether a medicine called gabapentin, which is a non-narcotic medicine, could help. Gabapentin is approved by the U.S. Food and Drug Administration (FDA) for prevention of seizures and for treating nerve pain and doctors are also using it to decrease pain for people having surgical procedures.

The main goals of our study are to learn about:

1. Women's pain experience with dilators in their cervix overnight before the abortion procedure
2. How well gabapentin works to decrease women's pain while they have the dilators in their cervix

Women who enroll in the study will get a dose of either gabapentin or placebo (a pill with no medicine in it) before their dilators are placed in the clinic. The medication they get (gabapentin or placebo) will be chosen by chance, like flipping a coin. Neither the women in the study nor the doctors giving them the medication will know which medication they receive so the investigators can learn about their pain without being influenced by knowing which medication they take. Doctors will be able to find out which medication women got if there is an emergency or if it changes their medical care.

The investigators will communicate with women in real time overnight by text messaging to see how much pain they are having in the moment and how much pain medicine they are taking.

The investigators hypothesize that women who receive gabapentin will have a smaller increase in their pain with the dilators than women who receive placebo (a pill with no medicine in it).

The investigators' findings will help doctors understand women's pain experience with dilators better and possibly provide a new way of treating pain with gabapentin.

The investigators have planned a double-blind randomized controlled trial of repeated doses of gabapentin compared to placebo for pain management during the time after dilator insertion and prior to D\&E the subsequent day.

* Participants will receive gabapentin 600 mg or placebo prior to dilator insertion
* Pain scores will be measured via numeric rating scale (NRS) at baseline and 5 minutes after last dilator insertion while the participant is in clinic
* Additional pain scores, side effects (specifically dizziness and sedation), and additional analgesic use will be obtained by text message while the patient is home at 2 hours, 4 hours, and 8 hours after time of dilator insertion
* Subjects will take a second dose of study drug (either gabapentin 600 mg or placebo, concordant with their initial medication) at 8 hours after their first dose
* Final pain score, side effect, and analgesic use assessment will occur upon presentation to the pre-operative are for D\&E the subsequent day

There will be no change in standard insertion of osmotic dilators (hygroscopic dilators only with Lidocaine 20mL cervical anesthesia), or provision of home analgesic medications (ibuprofen and acetaminophen with codeine in our practice).

The investigators hypothesize that women who receive gabapentin will report a smaller increase in pain from baseline at 8 hours after dilator placement compared to women receiving placebo.

Eligibility Criteria:
Inclusion Criteria:

* 15 weeks 0 days gestational age - 23 weeks 5 days gestational age at time of dilator insertion
* Able to read and write in English
* Active cell phone with text messaging capability
* Ride home from dilator insertion clinic appointment

Exclusion Criteria:

* Current use of gabapentin or pregabalin
* Allergy to gabapentin, acetaminophen, codeine, or ibuprofen
* Self reported renal disease (severe impaired renal function)
* Self reported current or chronic narcotic use (typical daily use)
* Women with any issue that, in the opinion of the investigator, would interfere with study participation or generating accurate study data