Clinical efficacy of dienogest against endometriomas with a maximum diameter of ≥4 cm

This prospective observational study aims to demonstrate the clinical efficacy of dienogest in treating endometriomas with a maximum diameter of ≥4 cm.

Patients (n = 81) with endometriomas (diameter of ≥4 cm) were enrolled and administered orally with dienogest (2 mg daily) and followed up for a year [Ethical approval code: 2020 Research 343]. Further, the efficacy was determined by recording the largest diameter and volume of the endometriomas, uterine volume, endometrial thickness, and the largest diameter of uterine fibroids in the patients during 0, 6, and 12 months. The pain symptoms were assessed using the Numerical Rating Scale (NRS), and the side effects of medication were monitored. With the consent, some patients underwent routine blood tests, and serum hormone, as well as Anti-Müllerian Hormone (AMH) levels were measured.

The dienogest treatment resulted in a significant reduction of the maximum diameter of these cysts from 50.5 mm to 41 mm in 6 months and 34 mm in 12 months. In addition, the volume of the cysts significantly decreased from 37.8 ml from baseline to 18.5 ml in 6 months and 11.8 ml in 12 months. Among 26 subjects with ultrasonic signs of endometrial polyps, 92.3% of cases displayed no polyps after 12 months. No significant changes were observed in the size of uterine fibroids and AMH levels. The NRS score showed a decrease from an average of 6.6-1.2 in 12 months.

Dienogest could effectively reduce the diameter and volume of endometriomas with a maximum diameter of ≥4 cm, improving anemia, as well as pain symptoms and preserving ovarian function.