(28) Comparing Efficacy and Side Effects of Norethindrone Acetate versus Combined Oral Contraceptives in Patients with Acute Abnormal Uterine Bleeding

Background: Abnormal uterine bleeding (AUB) is common among preteens and adolescents, but its management is varied in clinical practice. There are currently no studies that compare the efficacy of norethindrone acetate (NA) with combined oral contraceptives (COC) in managing adolescents with acute AUB. Our pilot study hypothesizes that NA would have less side effects compared to COC and be just as efficacious.

Methods: This prospective study was approved by the Institutional Review Board (Tracking ID 20216738). We identified adolescent females aged 10 to 21 with a diagnosis of AUB or other specified irregular menses per ICD 10 criteria from January 2022 to March 2023 who were first treated at a single children’s hospital emergency department and then enrolled at our Adolescent Medicine clinic. Those who were currently pregnant, had a history of known bleeding disorders, or had contraindications to estrogen were excluded. Patients were consented. Data collection was performed via questionnaires and duration of bleeding, presence of anemia, hospitalizations related to bleeding, and days until bleeding cessation with treatment were prioritized. Adherence with medication, satisfaction, and side effects were also recorded. All the variables were observed descriptively. Statistical analysis was performed using two sample T-tests and chi-square tests with alpha 0.05.

Results: Fifteen patients were recruited. Eight patients were treated with COC and seven were treated with NA. The mean age (SD) of the patients in the COC group was 14.3 (1.98) and in the NA group was 11.1 (1.06) (P = 0.003). Other patient characteristics of adolescents with AUB are summarized in Table 1.
Clinical manifestations of COC and NA administrations are summarized in Table 2. There was no statistical significance between the average length of stay in the hospital (P = 0.913) and the time to bleeding cessation (P= 0.944) between the two treatment groups. Patients who took NA (6 patients, 86%) experienced no side effects compared to the COC group (2 patients, 25%) (P < 0.05). There was no statistical significance in patient compliance or satisfaction.

Conclusions: Based on our results, NA appears to be just as efficacious as COC. We found that the time to bleeding cessation and length of hospital stay was no different between the two groups; however, there was a statistical significance difference in the side effects profile. Those treated with NA had fewer side effects than those treated with COC. We hope this pilot study will promote further inquiries as to whether NA may be the better choice for acute AUB in young women.