The goal of this clinical trial is to learn whether cabergoline can prevent lactation and reduce breast symptoms in pregnant people aged 18 years or older undergoing abortion or pregnancy loss between 12 and 18 weeks of gestation. The main questions it aims to answer are:

Does cabergoline decrease the proportion of participants who experience breast symptoms (including breast engorgement, milk leakage, tenderness, and need for pain relief) after abortion or pregnancy loss?

Does cabergoline reduce the severity of breast symptoms and associated bother compared with placebo?

Researchers will compare participants receiving cabergoline to those receiving placebo to determine whether cabergoline reduces the frequency and severity of breast symptoms following abortion or pregnancy loss.

Participants will:

Complete a baseline survey assessing breast symptoms prior to the abortion or pregnancy loss procedure

Receive a single oral dose of either cabergoline (1 mg) or placebo approximately one hour after the procedure

Complete follow-up surveys on days 2, 3, 4, 7, and 14 after the procedure to assess breast symptoms and related bother

A subset of participants will provide blood samples at selected time points to measure serum prolactin levels

Breast symptoms such as breast engorgement, milk leakage, and tenderness are common after abortion or pregnancy loss in the second trimester because lactation can begin as early as 12-20 weeks of gestation. While care following abortion or pregnancy loss often focuses on pelvic symptoms, breast symptoms may also cause significant physical discomfort and emotional distress for patients. Prior research suggests that a large proportion of patients undergoing abortion or pregnancy loss between 14 and 20 weeks experience breast tenderness, engorgement, or milk production. However, the frequency and severity of these symptoms earlier in the second trimester (12-18 weeks) has not been well characterized.

Historically, medications such as bromocriptine were used to suppress lactation following pregnancy termination or delivery. However, bromocriptine has been associated with serious cardiovascular, neurologic, and psychiatric side effects and is no longer recommended for lactation suppression in the United States. Cabergoline, a dopamine agonist that suppresses prolactin secretion, has emerged as a safer alternative and has been shown to be effective in suppressing lactation after full-term delivery. More recent studies suggest that cabergoline may also reduce breast symptoms following abortion or pregnancy loss in the later second trimester, but limited evidence exists for individuals between 12 and 18 weeks of gestation.

This study aims to evaluate both the prevalence of breast symptoms and the effectiveness of cabergoline for preventing these symptoms among individuals undergoing abortion or pregnancy loss between 12 and 18 weeks of gestation.

The study will include two phases conducted at Maimonides Medical Center. In the first phase, participants will complete a survey assessing baseline breast symptoms prior to the abortion or pregnancy loss procedure. The survey will use the Bristol Breast Symptoms Inventory, a validated instrument that measures the severity of breast engorgement, milk leakage, tenderness, and the need for pain relief. This phase will allow researchers to estimate how frequently breast symptoms occur in this population.

In the second phase, participants will be enrolled in a double-blind randomized controlled trial. Participants will be randomly assigned to receive either a single oral dose of cabergoline (1 mg) or a placebo approximately one hour after the abortion or pregnancy loss procedure. Both participants and clinical providers will be blinded to the treatment assignment.

Participants will complete follow-up surveys on days 2, 3, 4, 7, and 14 after the procedure to assess the presence and severity of breast symptoms as well as the level of bother caused by these symptoms. The primary outcome of the study will be the proportion of participants reporting breast symptoms four days after the procedure. Secondary outcomes include the severity of individual breast symptoms, overall symptom bother, and participant satisfaction.

A subset of approximately 20 participants will also be invited to provide blood samples at several time points during the study to measure serum prolactin levels. These measurements will help evaluate the biological effect of cabergoline on lactation-related hormone levels. Participation in blood sampling will be optional and not required for participation in the main study.

By evaluating both the frequency of breast symptoms and the effectiveness of cabergoline for preventing them, this study aims to improve clinical care and patient comfort for individuals undergoing abortion or pregnancy loss in the early second trimester.

Inclusion Criteria:

• Pregnant people aged 18 years or older
• Gestational age between 12 and 18 weeks
• Undergoing treatment for spontaneous or induced abortion at Maimonides Medical Center
• Able to provide informed consent
• Willing and able to complete study surveys

Exclusion Criteria:

• Prior mastectomy
• Currently breastfeeding
• Current use of a dopamine agonist or dopamine antagonist medication
• Known contraindication to Cabergoline according to the medication prescribing information

Individual participant data will not be shared due to privacy concerns and the potential risk of participant identification given the sensitive nature of the study population and clinical context. Only aggregate study results will be reported.

Double-blinded (Participant, Care Provider)