Mouse ovarian follicle cryopreservation using vitrification or slow programmed cooling: assessment of in vitro development, maturation, ultra-structure and meiotic spindle organization.

AIM: To compare different outcomes of vitrification and slow freezing of isolated pre-antral follicles and to evaluate different cryo-devices for vitrification of isolated follicles. METHODS: Pre-antral follicles were isolated from mouse ovaries and cryopreserved using vitrification and slow freezing. A preliminary experiment was carried out to select the optimal cryo-device for vitrification of isolated follicles. A total of 414 follicles were randomly distributed among four groups: control (CT) fresh (n=100), nylon mesh (n=96), electron microscopy grid (n=102), and micro-capillary tips (n=116). Subsequently, a total of 979 follicles were randomly assigned to three different groups: CT fresh (n=256), vitrification (n=399) and slow freezing (n=324). CT and cryopreserved/thawed follicles were cultured in vitro and examined daily for development. Final maturation was triggered with human chorionic gonadotrophin and rates of oocyte maturation were calculated. The ultra-structure of cryopreserved/thawed follicles was studied using electron microscopy. Meiotic spindle presence and organization in mature oocytes were examined using the Oosight imaging system. RESULTS: Micro-capillary tips resulted in poor immediate post-warming survival but no differences were observed in the subsequent in vitro development characteristics between different cryo-devices. Nylon mesh proved to be the easiest carrier, particularly when large numbers of follicles were to be vitrified. Compared to vitrification, slow freezing resulted in a significantly lower number of intact follicles at the end of the culture period (P<0.0001). However all other outcome measures were comparable between both techniques. CONCLUSIONS: Isolated follicles were more vulnerable to cryodamage after slow freezing as compared to vitrification.

Prediction of successful menorrhagia treatment after thermal balloon endometrial ablation.

BACKGROUND: Thermal balloon endometrial ablation (TBEA) is a non-hysteroscopic technique, which relies on a combination of heat and pressure within the uterine cavity to destroy endometrium and superficial myometrium. It is a simple, easy and minimally invasive procedure with an equivalent effectiveness to hysteroscopic endometrial ablation. OBJECTIVES: To evaluate the effectiveness of TBEA in the treatment of menorrhagia and to identify the possible predictive factors for a successful outcome after 2-year follow-up. METHODS: A prospective study was conducted, including 45 patients suffering from serious menorrhagia. Under local anesthesia with i.v. sedation, the Therma-Choice trade mark (Gynecare, Somerville, NJ, USA) balloon was inserted transcervically and after inflation in the endometrial cavity with 5% dextrose, it was heated to 87 degrees C for an 8-minute treatment cycle. RESULTS: There were no intraoperative complications and postoperative morbidity was minimal. At 2-year follow-up the overall improvement of menstrual pattern was 85%; with reported 29% amenorrhea, 23.5% hypomenorrhea and 32.5% euomenorrhea. Menorrhagia persisted in 15% of patients. Multiple logistic regression analysis of the factors that could affect the outcome showed that the chance for a successful treatment increased significantly with increased age (P = 0.044), shorter uterine depth (P = 0.049) and adequate balloon pressure (P = 0.027). These were the predictive factors for successful outcome. However, parity, uterine volume and endometrial thickness were not predictive factors. CONCLUSION: At 2-year follow-up, thermal balloon endometrial ablation is effective in menorrhagia treatment. Increased age, shorter uterine depth and adequate balloon pressure can be predictive factors for successful treatment.