Abstract：
Although abnormally fertilized zygotes with three or multiple pronuclei (3 PN/MPN) are commonly believed to be associated with improper maturation of the oocyte cytoplasm in conventional IVF cycles, no studies investigated the association between the proportion of MPN zygotes and the maturation state of the oocyte cohort. We compared the cytoplasmic maturity of oocytes from conventional IVF cycles with different proportions of 3 PN/MPN zygotes. A total of 1428 conventional IVF patients with ≥6 oocytes retrieved and fresh embryos transferred were divided into 4 groups according to the proportions of 3 PN/MPN zygotes. The pregnancy outcomes and the proportion of nuclear immature oocytes were analyzed to suggest the cytoplasmic maturation state of the oocyte cohort. Our results showed that the group with a low proportion of 3 PN/MPN zygotes had a higher clinical pregnancy rate (CPR) than those without 3 PN/MPN zygotes (P < 0.05). However, the live birth rate (LBR) was not significantly different between the two groups. The implantation rate (IR), CPR, and LBR did not differ between the low-proportion and high-proportion 3 PN/MPN groups. The proportion of nuclear immature oocytes on day 1 was highest in the group without 3 PN/MPN zygotes (23.8 %) and gradually decreased with an increased proportion of 3 PN/MPN zygotes (P < 0.001). Therefore, the presence of 3 PN/MPN zygotes after conventional IVF may indicate a more mature cytoplasmic state of the oocyte cohort, and the increased proportion of 3 PN/MPN zygotes is associated with an increased maturation state of the whole oocyte cohort. The occurrence and proportion of 3 PN/MPN zygotes may serve as an indicator for the cytoplasmic maturity of the oocyte cohort and help clinicians evaluate the efficiency of ovarian stimulation and optimize the stimulation protocols in subsequent cycles.
摘要：
尽管通常认为具有三个或多个原核（3PN/MPN）的异常受精卵与常规IVF周期中卵母细胞细胞质的不适当成熟有关，没有研究调查MPN受精卵比例与卵母细胞队列成熟状态之间的关联。我们比较了不同比例的3个PN/MPN受精卵的常规IVF周期卵母细胞的细胞质成熟度。根据3个PN/MPN受精卵的比例，将1428例获得≥6个卵母细胞并移植新鲜胚胎的常规IVF患者分为4组。分析妊娠结局和核未成熟卵母细胞的比例，以提示卵母细胞队列的细胞质成熟状态。我们的结果表明，3个PN/MPN合子比例较低的组的临床妊娠率（CPR）高于没有3个PN/MPN合子的组（P<0.05）。然而,两组活产率(LBR)无显著差异。植入率（IR），CPR,低比例和高比例3PN/MPN组之间的LBR没有差异。第1天核未成熟卵母细胞的比例在无3个PN/MPN受精卵组中最高(23.8%),随着3个PN/MPN受精卵比例的增加而逐渐下降(P<0.001)。因此,常规IVF后3个PN/MPN受精卵的存在可能表明卵母细胞队列的细胞质状态更成熟,3个PN/MPN受精卵的比例增加与整个卵母细胞队列的成熟状态增加有关。3个PN/MPN受精卵的发生和比例可以作为卵母细胞队列的细胞质成熟度的指标，并帮助临床医生评估卵巢刺激的效率并优化后续周期的刺激方案。
