Effect of Paracervical Block Volume on Pain Control for Dilation and Curettage

The investigators are conducting a study on pain control for dilation and curettage (D&C). Participants are eligible to enroll if they are a planning to have a D&C in a participating clinic. The investigators are studying how different ratios of medication to liquid affect pain when injected around the cervix. Both potential methods use the same dose of medication, though researchers would like to know which one works better. To be in this study, participants must be over the age of 18 with an early pregnancy loss or undesired pregnancy measuring less than 12 weeks gestation undergoing D&C while awake in clinic.

Dilation and Curettage (D&C) is often performed in the first trimester for surgical abortion and management of miscarriage and can be painful for patients before and after the procedure. Most procedures are performed while the patient is awake or with minimal sedation in the clinic setting, and a key component of pain control is the paracervical block, or injecting lidocaine into the tissue around the cervix. A paracervical block with 20cc of 1% buffered lidocaine has been proven to provide superior pain control than a sham paracervical block. However, many providers often use similar doses of lidocaine in a higher volume to improve pain control. At University of California, San Diego (UCSD) and University of California, Los Angeles (UCLA), some providers routinely use a 20cc of 1% buffered lidocaine block and some routinely use a 40cc of 0.5% buffered lidocaine block. This practice has not been studied in a randomized controlled trial. The purpose of this study is to compare pain control during D&C with a 20cc 1% buffered lidocaine with vasopressin paracervical block compared to a 40cc 0.5% buffered lidocaine with vasopressin paracervical block. An inclusion criterion for this study is that patients must specifically be referred to family planning clinics at UCSD and UCLA for an in-clinic D&C. Therefore, the D&C is a required procedure for both study groups. The only difference in care between the study groups will be which paracervical block they receive.