A study in the Journal of Obstetrics and Gynaecology found that dienogest was effective in decreasing the size of endometrioma and reducing endometriosis-associated pain, along with a favorable safety and tolerability profile.
The prospective study from Turkey recruited 30 patients diagnosed with endometrioma at Erciyes University Medical Faculty Hospital in Kayseri, Turkey, between November 2015 and September 2016.
Only 24 patients were included in the study because three patients were unable to complete the dienogest therapy due to menstrual irregularities, two patients did not attend to regular controls, and one patient was operated on at another hospital.
The mean age of the 24 patients was 29.58 years, with a mean body mass index (BMI) of 25.9. The endometriomas in 86.67% of the patients were unilateral.
Patients were instructed to take a single daily 2 mg dose of the synthetic oral progestogen continuously through the 6-month study period, preferably at the same time each day.
Patients were examined for efficacy and side effects at baseline, 3 months and 6 months.
The mean volume of the endometrioma decreased a significant 41% from 112.63 ± 161.31 cm³ at baseline to 65.47 ± 95.69 cm³ at 6-month follow-up (P = 0.005).
A visual analog scale (VAS) from 0 to 10 (0: no pain, 10: unbearable pain) for pelvic pain also decreased significantly from 7.50 to 3.00 at 6 months after treatment (P < .001).
The most common side effect was abnormal vaginal bleeding, consisting of prolonged and frequent uterine bleeding or spotting (16.6%), followed by weight gain (8.3%), headache (8.3%), depressed mood (8.3%), dizziness (4.1%) and libido reduction (4.1%).
“Laparoscopic excisional surgery for endometrioma is currently the most valid approach in the treatment of endometriomas,” wrote the authors. “However, there are concerns about ovarian reserve damage during surgery.”
Because there is no consensus on the timing of surgery in young women and whether surgery should be delayed in infertile women planning in vitro fertilization (IVF), strategies to eliminate or decrease the size of ovarian endometriomas without affecting a young woman’s fertility potential need to be designed, according to the authors.
One potential solution is presurgical administration of a gonadotropin-releasing hormone agonist (GnRH agonist), which renders conservative laparoscopic surgery easier for endometriosis and might reduce postsurgical damage to ovarian function by reducing active inflammation, adhesion of endometriotic lesions and the size of the endometrial cysts.
However, GnRH agonist therapy causes adverse effects by the deficiency of the ovarian hormone, such as an irregular menstrual period, hot flashes, vaginal burning, decreased sexual interest, and bone mineral density loss.
On the other hand, dienogest for IVF patients with an endometrial cyst prior to oocyte pick-up might facilitate oocyte pick-up and prevent bacterial infection post-procedure.
“Long-term use of dienogest in younger patients with endometriomas who are yet to give birth may reduce the possibility of surgery by reducing the size of the endometriomas and may preserve ovarian reserve,” wrote the authors.
In addition, dienogest could reduce the incidence of infectious complications from pelvic abscess after oocyte retrieval and from surgical procedures for infertile patients with endometrioma.
The authors said clinicians should consider dienogest prior to initiation of an IVF cycle to reduce endometrioma size.
Uludag SZ, Demirtas E, Sahin Y, Aygen EM. Dienogest reduces endometrioma volume and endometriosis-related pain symptoms. J Obstet Gynaecol. Published online February 25, 2021. doi:10.1080/01443615.2020.1867962