Avrech O M, Goldman G A, Rufas O, Stein A, Amit S, Yoles I, Pinkas H, Fisch B
Department of Obstetrics and Gynecology, Beilinson Medical Center, Petah-Tiqva, Israel.
J Assist Reprod Genet. 1997 Jul;14(6):337-42. doi: 10.1007/BF02765838.
In an effort to understand the mechanism underlying the improved pregnancy rate observed in IVF cycles when gonadotropin-releasing hormone analogues (GnRH-a) are applied, we investigated a possible relationship between treatment variables and oocyte nuclear maturity.
Nuclear maturity was retrospectively assessed in cumulus-free, denuded oocytes, obtained from women undergoing micromanipulation-assisted IVF treatment following controlled ovarian hyperstimulation with GnRH-a and menotropins.
The setting was the infertility and IVF unit of a tertiary academic medical center.
Two hundred twenty-one patients underwent 435 treatment cycles.
This was the proportion of germinal vesicle-intact immature (GVII) oocytes.
One hundred fifty-four of the 3520 oocytes studied (4.4%) were in the GVII stage. These oocytes were found in 66 of the treatment cycles (15.2%) and in 54 of the patients (24.4%). Cycles in which GVII oocytes were detected did not differ from those in which all the aspirated oocytes were mature in the following respects: patient age, type and duration of infertility, controlled ovarian hyperstimulation protocol and time of ovum pickup. However, the GVII group was characterized by a significantly higher peak estradiol level, as well as a higher number of mature follicles visualized sonographically (diameter, > 14 mm) and oocytes retrieved.
Comparing the present findings with previously published data, it appears that the inclusion of GnRH-a in the stimulation regimen is associated with a lower proportion of immature oocytes. A higher occurrence of oocyte-nuclear immaturity is apparently associated with a significantly better ovarian response to stimulation. The high incidence of immature oocytes observed in patients with normospermic partners and low fertilization rates in previous cycles may suggest that the fertilization failure in some of these cases is due to oocyte, rather than sperm, dysfunction.
为了了解在体外受精（IVF）周期中应用促性腺激素释放激素类似物（GnRH-a）时观察到的妊娠率提高的潜在机制，我们研究了治疗变量与卵母细胞核成熟度之间的可能关系。
对无卵丘、裸卵的核成熟度进行回顾性评估，这些卵母细胞来自接受GnRH-a和促性腺激素控制性卵巢过度刺激后进行显微操作辅助IVF治疗的女性。
研究地点为一家三级学术医学中心的不孕不育与IVF科室。
221名患者接受了435个治疗周期。
这是生发泡完整的未成熟（GVII）卵母细胞的比例。
在研究的3520个卵母细胞中，有154个（4.4%）处于GVII期。这些卵母细胞出现在66个治疗周期（15.2%）和54名患者（24.4%）中。检测到GVII卵母细胞的周期在以下方面与所有吸出卵母细胞均成熟的周期没有差异：患者年龄、不孕类型和持续时间、控制性卵巢过度刺激方案以及取卵时间。然而，GVII组的特征是雌二醇峰值水平显著更高，以及超声检查可见的成熟卵泡数量更多（直径>14 mm）和回收的卵母细胞数量更多。
将目前的研究结果与先前发表的数据进行比较，似乎在刺激方案中加入GnRH-a与未成熟卵母细胞比例较低有关。卵母细胞核未成熟的发生率较高显然与卵巢对刺激的反应明显更好有关。在前一轮周期中，精子正常的伴侣的患者中观察到未成熟卵母细胞的高发生率以及低受精率，这可能表明这些病例中的一些受精失败是由于卵母细胞功能障碍，而非精子功能障碍。
