OC15.01: Impact of repeated ovarian stimulations on ultrasonographic features of deep endometriotic nodules

Ovarian hyperstimulation for in vitro fertilisation (IVF) is associated with a significant rise in serum estrogens, which may have detrimental effects on endometriosis. This study investigates the impact of repeated ovarian stimulations on the ultrasonographic size of deep endometriotic (DE) nodules. This prospective study included women with endometriosis who underwent at least three ovarian stimulation for IVF within 12 months. The diagnosis of DE (uterosacral ligaments, bladder, rectovaginal, rectovaginal infiltrating the rectum) and ovarian endometriomas (OMA) was performed by transvaginal ultrasound. The size of DE nodules and OMA and the intensity of pain symptoms were systematically evaluated one month before each ovarian stimulation within 2 months after ovarian stimulation or the failed transfer. Changes in the volume of DE nodules were assessed at ultrasound by using the virtual organ computer-aided analysis (VOCAL). The study included 69 women (97 DE lesions; 37 OMA); the mean ( ± SD) age of the study population was 38.5 ( ± 2.6). The total number of ovarian stimulations was 231 with a median (range) of 3 (3-5) stimulation for each patient. After the last stimulation, the mean volume of DE nodules was significantly increased (3.92 ± 3.18 mm3 vs. 4.67 ± 3.87 mm3; p = 0.038) similarly to that of OMA (3.58 ± 2.84 mm3 vs. 4.26 ± 3.12 mm3; p = 0.014). The volume of DE lesions increased in 56.7% (n = 55/97), was stable in 32.9% (n = 32/97) and decreased in 11.4% (11/97) of cases. A new DE lesion was diagnosed in 8.7% (n = 6/97) of patients. There was a worsening in the intensity of dysmenorrhea (p = 0.025), chronic pelvic pain (p = 0.039), dyspareunia (p = 0.046), and dyschezia (p = 0.036). There was one case of bowel sub occlusion in a patient with rectal endometriosis. Women with DE undergoing repeated ovarian stimulation for IVF within a short period seem to be exposed to increased risk of lesion size growth and worsening of pain.