胚胎密度对卵裂期优质胚胎率的影响

Impact of embryo density on the proportion of good quality cleavage embryos

目的通过调整协变量来探索培养的胚胎密度与第3天卵裂期胚胎发育结果之间的相关性。方法回顾性分析206对夫妇1196个胚胎体外受精-胚胎移植(IVF-ET)治疗的资料。培养条件为低氧,培养液每微滴体积为30μl。以第3天卵裂期胚胎的优质胚胎率为终点指标对胚胎质量进行评价。选择女方年龄,男方年龄,窦卵泡数,抗苗勒管激素(AMH)水平,不孕症类型,控制性卵巢刺激(COS)方案,用药刺激时长,获卵数和授精方式为协变量。结果共有1196枚胚胎纳入分析,使用3种不同胚胎密度:30μl/胚[1枚胚胎/(30μl·滴)]、15μl/胚[2枚胚胎/(30μl·滴)]和10μl/胚[3枚胚胎/(30μl·滴)]进行培养,每组总胚胎数分别为434枚,646枚和116枚。10μl/胚组第3天胚胎的优质胚胎率显著低于15μl/胚和30μl/胚组(29.31%vs40.25%,P<0.05;29.31%vs 42.17%,P<0.05),15μl/胚和30μl/胚组之间的优质胚胎率差异不显著(40.25%vs 42.17%,P>0.05)。在回归分析中,不调整任何协变量,10μl/胚组第3天胚胎的优质胚胎率比30μl/胚组下降43%(0.57,95%CI 0.32,1.03),差异无统计学意义(P>0.05)。调整了女性参与者AMH水平和授精方式后,10μl/胚组第3天胚胎的优质胚胎率比30μl/胚组显著降低51%(0.49,95%CI 0.27,0.90,P<0.05)。结论在30μl微滴的低氧培养条件下,与单独培养相比,胚胎密度为10μl/胚的集合培养不利于卵裂期胚胎发育,30μl/胚为最适胚胎培养密度。

Objective To investigate the real correlation between embryo density and developmental outcome of cleavage embryos on day 3 by adjusting covariates.Methods Data of 1196 embryos from 206 couples undergoing in vitro fertilization and embryo transfer(IVF-ET)treatment were retrospectively analyzed.Embryos were hypoxia-cultivated in a fixed30μl microdrop in culture dishes.Embryo quality on day 3 was evaluated and proportion of good quality cleavage embryos on day 3 was used as the endpoint.Maternal age,paternal age,antral follicles,level of anti-mullerian hormone(AMH),type of infertility,controlled ovarian stimulation(COS)protocol,length of stimulation,number of retrieved oocytes,and type of insemination were chosen as covariates.Results A total of 1196 embryos were included and analyzed.Three embryo densities were routinely used:30μl/embryo[1 embryo/(30μl·drop)],15μl/embryo[2 embryos/(30μl·drop)]and 10μl/embryo[3 embryos/(30μl·drop)].The number of embryos assigned into these three groups were 434,646 and 116 embryos separately.The average proportion of good quality embryos on day 3 in 10μl/embryo group were lower than that in both 15 and 30μl/embryo group(29.31%vs 40.25%,P<0.05;29.31%vs 42.17%,P<0.05),and it was comparable between groups of 15 and 30μl/embryo(40.25%vs 42.17%,P>0.05).In the regression analysis,without adjusting any covariables,the good quality embryos rate on day 3 of the 10μl/embryo group was 43%lower than that of the 30μl/embryo group(0.57,95%CI 0.32,1.03),and there was no statistical difference(P>0.05).In the minimum-adjusted model 2(adjusted the level of AMH and type of insemination),proportion of good quality embryos on day 3 in group of 10μl/embryo significantly decreased by 51%(0.49,95%CI 0.27,0.90,P<0.05)compared with that in group of 30μl/embryo.Conclusion In a 30μl microdrop,compared with individual cul turing,group culturing with the density of 10μl/embryo did not benefit the development of the cleavage embryos and 30μl/embryo was the optimal embryo density.