To assess cabergoline's efficacy at decreasing lactation after second-trimester abortion
This is a double-blinded, block-randomized superiority trial (IRB approved, NCT04701333)
comparing cabergoline 1mg once to placebo for preventing bothersome breast engorgement
after second-trimester uterine evacuation. April 2021-June 2022, we enrolled pregnant
people 18-28-weeks gestation, English- or Spanish-speaking, without contraindication
to the study drug. Participants completed a validated, piloted, electronic survey
at baseline and through two weeks post-procedure assessing breast symptoms, side-effects,
and bother at each time point. Our primary outcome is breast symptoms on day 4; we
planned to enroll 80 patients to show a 30% difference in breast symptoms (80% power,
α = 0.049). A sub-group of participants returned for serum prolactin levels.
After screening 150 patients, we enrolled 73 participants. Baseline demographics were
balanced between groups: median gestational age 21 weeks (range: 18-26), 56% nulliparous,
35% self-identified as Hispanic, 37% with public insurance. At baseline, reported
breast symptoms were similar between groups. At day 4, significantly fewer participants
receiving cabergoline reported any symptoms compared to placebo (27.8% vs 97.0%, p<0.0001)
and fewer reported significant bother (2.8% vs 29.7%, p=0.002). These differences
persisted through day 14. Reported side-effects (p=0.31) were similar between groups:
most common were constipation (44%), fatigue (32%), and headache (29%). Serum prolactin
was similar at baseline. On day 4, mean serum prolactin was 6.5ng/mL (std dev 2.2)
for those receiving cabergoline and 18.0ng/mL (std dev 5.9) for placebo (p=0.04).
Cabergoline is an effective strategy to prevent breast symptoms following second-trimester
abortion or loss.