Cabergoline for Lactation Inhibition After Second-Trimester Abortion or Loss

This research study investigates the use of a drug, cabergoline, given immediately after second-trimester abortion or perinatal loss to decrease breast engorgement. Cabergoline is a medication approved for the symptomatic treatment of pituitary adenomas that result in a hyperprolactinemic state (a brain tumor that results in milk leakage). The benefit of stopping milk leakage has also been studied and used in populations who shouldn't breastfeed. The investigators aim to clarify if cabergoline is effective in preventing breast engorgement and milk leakage after second-trimester abortions or perinatal loss (stillbirth). Breast engorgement causes physical pain and emotional distress as lactation is uniquely associated with parenthood and those undergoing second-trimester abortions are doing so because they choose not to parent or a previously desired pregnancy is now complicated by anomalies. As there are no current recommendations for management of this painful engorgement beyond icepacks and support bras, the investigators aim to validate the use of this pharmacologic option in this setting.

Breast pain following second-trimester abortion is common. Breast engorgement and milk leakage following second-trimester perinatal loss and abortion can cause both physical pain and emotional distress. Dopamine agonists have previously been shown to be effective in lactation inhibition for third-trimester fetal/neonatal loss or contraindications to breastfeeding. In a head-to-head trial, cabergoline was more effective with a better safety profile than bromocriptine and has thus emerged as preferred treatment for term lactation inhibition internationally. Despite the frequency of breast symptoms after second-trimester abortions, there are no current guidelines for this population.

The investigators are conducting a double-blinded, placebo-controlled, superiority trial of participants undergoing abortion or experiencing intrauterine fetal demise between 18 and 28-weeks gestation at Stanford Health Care. Participants will be randomized to either cabergoline 1mg or placebo the day of procedure. Participants will complete the Bristol Breast Inventory, a survey to assess symptoms and side-effects at baseline and day 2, 3, 4, 7, and 14 after the procedure.

The primary outcome is breast symptoms on Day 4 as reported on the Bristol Breast Inventory. Secondary outcomes include satisfaction, acceptability, and side-effects. Investigators hypothesize that cabergoline is superior to placebo for preventing breast engorgement after second-trimester abortion or loss. A sub-study of 6 participants will return for serum prolactin levels at baseline, days 4, 7, 14 after procedure.

Eligibility Criteria:
Inclusion Criteria:

* Pregnant people, ages 18 years or older
* Intrauterine pregnancy between 18/0-28/0 weeks of gestation age (by ultrasound dating performed prior to or same day of enrollment visit)
* Consented for an induced, elective abortion or undergoing induction for demise
* English or Spanish speaking
* Able to consent for a research study, literate in English or Spanish
* Willing to comply with study procedures and follow-up
* Access to smart phone throughout study

Exclusion Criteria:

* Prior mastectomy (breast reduction or chest masculinization surgery acceptable)
* Currently breastfeeding
* Currently receiving dopamine agonist therapy for other indication (prolactinoma, Cushings syndrome, acromegaly, restless leg syndrome)
* Contraindication to cabergoline (as per package insert)

  * Uncontrolled hypertension - defined as baseline BP \> 150/100, or chronic hypertension requiring more than one baseline medication, or pregnancy-induced hypertension spectrum disorders (gestational hypertension, preeclampsia, eclampsia)
  * History of cardiac valvular disorders or valvular repair
  * History of pulmonary, pericardial, or retroperitoneal fibrotic disorders