Son Weon-Young, Henderson Sara, Cohen Yoni, Dahan Michael, Buckett William
Department of Obstetrics and Gynecology, MUHC Reproductive Centre, McGill University Health Center, McGill University, Montréal, QC, Canada.
Front Endocrinol (Lausanne). 2019 Jul 17;10:464. doi: 10.3389/fendo.2019.00464. eCollection 2019.
maturation (IVM) of human immature oocytes has been offered to women who are at risk of developing ovarian hyperstimulation syndrome (OHSS) caused by gonadotropin stimulation, such as PCO(S) patients or who have poor ovarian reserve. Cryopreservation of oocytes matured obtained in IVF cycles has improved after implementing the vitrification method and many successful results have been reported. Now, this procedure can be successfully offered to fertility preservation programs for patients who are in danger of losing their ovarian function due to medical or social reasons, and to oocyte donation programs. This vitrification technique has also been applied to cryopreserve oocytes obtained from IVM program. Some advantages of oocytes vitrification related with IVM are: (1) eliminating costly drugs and frequent monitoring; (2) completing treatment within 2 to 10 days (3) avoiding the use of hormones in cancer patients with hormone-sensitive tumors; and (4) retrieving oocytes at any point in menstrual cycle, even in the luteal phase. In addition, immature oocytes can also be collected from extracorporeal ovarian biopsy specimens or ovaries during caesarian section. Theoretically, there are two possible approaches for preserving immature oocytes: oocyte cryopreservation at the mature stage (after IVM) and oocyte cryopreservation at the Germinal Vesicle (GV)-stage (before IVM). Both vitrification of immature oocyte before/after IVM is not currently satisfactory. Nevertheless, many IVF centers worldwide are doing IVM oocyte cryopreservation as one of the options to preserve fertility for female cancer. Therefore, more studies are urgently required to improve IVM- and vitrification method to successfully preserve oocytes collected from cancer patients. In this review, present oocyte maturation mechanisms and recent progress of human IVM cycles will be discussed first, followed by some studies of the vitrification of human IVM oocyte.
对于有因促性腺激素刺激而发生卵巢过度刺激综合征（OHSS）风险的女性，如多囊卵巢综合征（PCOS）患者或卵巢储备功能差的女性，已为其提供人未成熟卵母细胞的体外成熟（IVM）技术。在采用玻璃化冷冻方法后，体外受精（IVF）周期中获得的成熟卵母细胞的冷冻保存情况有所改善，并且已有许多成功案例报道。现在，该程序可成功应用于因医学或社会原因面临卵巢功能丧失风险的患者的生育力保存计划以及卵母细胞捐赠计划。这种玻璃化冷冻技术也已应用于冷冻保存从IVM程序获得的卵母细胞。与IVM相关的卵母细胞玻璃化冷冻的一些优点包括：（1）省去昂贵的药物和频繁的监测；（2）在2至10天内完成治疗；（3）避免在患有激素敏感性肿瘤的癌症患者中使用激素；（4）可在月经周期的任何时间，甚至在黄体期采集卵母细胞。此外，未成熟卵母细胞也可从体外卵巢活检标本或剖宫产时的卵巢中采集。理论上，保存未成熟卵母细胞有两种可能的方法：成熟阶段（IVM后）的卵母细胞冷冻保存和生发泡（GV）期（IVM前）的卵母细胞冷冻保存。目前，IVM前后未成熟卵母细胞的玻璃化冷冻效果均不尽人意。尽管如此，全球许多IVF中心都在进行IVM卵母细胞冷冻保存，作为为女性癌症患者保存生育力的选择之一。因此，迫切需要更多研究来改进IVM和玻璃化冷冻方法，以成功保存从癌症患者采集的卵母细胞。在本综述中，将首先讨论目前的卵母细胞成熟机制和人类IVM周期的最新进展，随后介绍一些关于人类IVM卵母细胞玻璃化冷冻的研究。
