Gabapentin for Pain Control After Osmotic Dilator Insertion and Prior to D&E Procedure: a Randomized Controlled Trial (GABA)
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ClinicalTrials.gov Identifier: NCT03080493 |
Recruitment Status :
Completed
First Posted : March 15, 2017
Results First Posted : April 14, 2020
Last Update Posted : April 14, 2020
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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:
- Women's pain experience with dilators in their cervix overnight before the abortion procedure
- 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.
Condition or disease | Intervention/treatment | Phase |
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Abortion, Induced Cervical Preparation Pain | Drug: Gabapentin 600mg Drug: Placebo oral capsule Drug: acetaminophen/codeine and ibuprofen | Phase 4 |
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.
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 121 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Intervention Model Description: | Randomized placebo controlled trial, stratified block randomization based on prior vaginal parity (vaginal parity - yes or no). Goal of even distribution of prior vaginal parity between gabapentin and placebo groups as may impact osmotic dilator pain experience |
Masking: | Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor) |
Primary Purpose: | Treatment |
Official Title: | Gabapentin for Pain Control After Osmotic Dilator Insertion and Prior to D&E Procedure: a Randomized Controlled Trial |
Actual Study Start Date : | March 20, 2017 |
Actual Primary Completion Date : | November 5, 2018 |
Actual Study Completion Date : | November 5, 2018 |

Arm | Intervention/treatment |
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Active Comparator: Gabapentin
Gabapentin 600 mg PO - first dose in clinic prior to osmotic dilator placement, second dose 8 hours later (at home) Will receive standard regimen of acetaminophen/codeine and ibuprofen to take as needed for pain overnight |
Drug: Gabapentin 600mg
Gabapentin 600 mg PO (two total doses, thereby lasting duration while osmotic dilators are in place)
Other Name: Neurontin Drug: acetaminophen/codeine and ibuprofen Over the counter analgesic medications
Other Names:
|
Placebo Comparator: Placebo oral capsule
Matched placebo Will receive standard regimen of acetaminophen/codeine and ibuprofen to take as needed for pain overnight |
Drug: Placebo oral capsule
Packaged identical to gabapentin dosing
Other Name: Carboxymethyl cellulose Drug: acetaminophen/codeine and ibuprofen Over the counter analgesic medications
Other Names:
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- Mean Change From Baseline in NRS Pain Score at 8 Hours After Dilator Insertion [ Time Frame: 8 hours after insertion of last osmotic dilator ]Pain score based on numeric rating scale (NRS [0 lowest value to 10 highest value, in which 0 is the lowest amount of pain and 10 is the highest amount of pain]); Baseline obtained prior to study drug ingestion/dilator insertion. NRS pain score obtained via text message.
- Mean Change From Baseline in NRS Pain Score at 5 Minutes After Last Dilator Insertion [ Time Frame: 5 minutes after insertion of last osmotic dilator ]Pain score based on numeric rating scale (NRS [0 lowest value to 10 highest value, in which 0 is the lowest amount of pain and 10 is the highest amount of pain]); Baseline obtained prior to study drug ingestion/dilator insertion. NRS pain score obtained in person before subject leaves clinic appointment.
- Mean Change From Baseline in NRS Pain Score at 2 Hours After Dilator Insertion [ Time Frame: 2 hours after insertion of last osmotic dilator ]Pain score based on numeric rating scale (NRS [0 lowest value to 10 highest value, in which 0 is the lowest amount of pain and 10 is the highest amount of pain]); Baseline obtained prior to study drug ingestion/dilator insertion. NRS pain score obtained via text message.
- Mean Change From Baseline in NRS Pain Score at 4 Hours After Dilator Insertion [ Time Frame: 4 hours after insertion of last osmotic dilator ]Pain score based on numeric rating scale (NRS [0 lowest value to 10 highest value, in which 0 is the lowest amount of pain and 10 is the highest amount of pain]); Baseline obtained prior to study drug ingestion/dilator insertion. NRS pain score obtained via text message.
- Mean Change From Baseline in NRS Pain Score at Time of Presentation for D&E Procedure (Day Following Dilator Insertion) [ Time Frame: Time of presentation for D&E (day after dilator insertion) ]Pain score based on numeric rating scale (NRS [0 lowest value to 10 highest value, in which 0 is the lowest amount of pain and 10 is the highest amount of pain]); Baseline obtained prior to study drug ingestion/dilator insertion. NRS pain score obtained in person upon presentation for D&E procedure.
- Number of Participants Using Narcotic Pain Medication (Acetaminophen/Codeine) [ Time Frame: Collected between each subject contact (2 hours, 4 hours, 8 hours after dilator insertion and at time of presentation for D&E procedure) ]Subject account of how many used acetaminophen/codeine (standard medications given for supplement NSAID as needed after dilator insertion)

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | Female |
Accepts Healthy Volunteers: | No |
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

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03080493
United States, California | |
University of California Davis Health System | |
Sacramento, California, United States, 95817 |
Principal Investigator: | Natasha Schimmoeller, MD, MPH, MA | University of California, Davis | |
Study Director: | Mitchell Creinin, MD | University of California, Davis |
Documents provided by University of California, Davis:
Responsible Party: | University of California, Davis |
ClinicalTrials.gov Identifier: | NCT03080493 |
Other Study ID Numbers: |
987072 |
First Posted: | March 15, 2017 Key Record Dates |
Results First Posted: | April 14, 2020 |
Last Update Posted: | April 14, 2020 |
Last Verified: | April 2020 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Abortion Osmotic dilators Gabapentin Text message |
Acetaminophen Ibuprofen Gabapentin Codeine Carboxymethylcellulose Sodium Analgesics, Non-Narcotic Analgesics Sensory System Agents Peripheral Nervous System Agents Physiological Effects of Drugs Antipyretics Anti-Inflammatory Agents, Non-Steroidal Anti-Inflammatory Agents Antirheumatic Agents Cyclooxygenase Inhibitors |
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