卵裂期与囊胚期胚胎移植妊娠安全性和出生性别比的比较

目的探讨卵裂期和囊胚期胚胎移植对妊娠安全性及出生性别比的影响。方法回顾性分析2012年8月至2015年8月在我院行助孕治疗的19 684个周期的临床资料,根据胚胎移植时间及方式的不同进行分组:卵裂期胚胎移植组(D3组,13 968个周期)和囊胚移植组(D5组,5 716个周期),D3组又分为D3鲜胚组(13 566个周期)和D3冻胚组(402个周期);D5组分为D5鲜胚组(153个周期)和D5冻胚组(5 563个周期)。分别比较各组的妊娠结局及出生男/女性别比情况。结果 D3组的移植胚胎数显著高于D5组(P0.05),但临床妊娠率、胚胎种植率、活产率均显著低于D5组(P0.05),出生男/女性别比亦显著低于D5组(P0.05),多胎率、流产率、早产率、围生儿死亡率和低出生体重儿率则显著高于D5组(P均0.05);D3鲜胚组的胚胎种植率显著低于D5鲜胚组(P0.05),多胎率、流产率、早产率和低出生体重儿率显著高于D5鲜胚组(P均0.05);D3冻胚组的临床妊娠率、胚胎种植率、剖宫产率和活产率显著低于D5冻胚组,流产率则显著高于D5冻胚组(P均0.05);D3鲜胚组的临床妊娠率、胚胎种植率和活产率显著低于D5冻胚组(P0.05),出生性别比亦显著低于D5冻胚组(P0.05),多胎率、流产率、早产率、剖宫产率、围生儿死亡率、胎儿畸形发生率、低出生体重儿率则显著高于D5冻胚组(P均0.05)。结论囊胚移植在移植较少胚胎的情况下,仍可获得较高的种植率、临床妊娠率和活产率,同时降低多胎率,且不增加过期产、巨大儿和胎儿畸形的风险。但其可能会提高出生男/女性别比,其对性别比的长远影响尚需进一步深入研究。

Comparison of pregnancy safety and sex ratio at birth of embryo transfer at cleavage stage or blastocyst stage

Objective:To study the effect of embryo transfer at cleavage stage or blastocyst stage on pregnancy outcome and sex ratio at birth.Methods:The data of 19 684 cycles of undergone assisted reproductive technology (ART) including 13 968 cycles of embryo transfer at cleavage stage and 5716 cycles of blastocyst transfer in our centers from Aug.2012 to Aug.2015 were retrospectively analyzed.The patients were divided into four groups:Day 3 fresh group (13 566 cycles of fresh embryo transfer at cleavage stage),Day 3 frozen-thawed group (402 cycles of frozen-thawed embryo transfer at cleavage stage),Day 5 fresh group (153 cycles of fresh blastocyst transfer),Day 5 frozen-thawed group (5 563 cycles of frozen-thawed blastocyst transfer).Clinical outcomes and sex ratio at birth were compared between cleavage stage and blastocyst embryo transfer.Results:The number of embryo transfer in Day 3 group was significantly higher than that in Day 5 group (P<0.05).The clinical pregnancy rate,implantation rate,live birth rate and male/female ratio at birth in Day 3 group were significantly lower than those in Day 5 group (all P<0.05).The multiple pregnancy rate,abortion rate,premature birth rate,perinatal mortality and incidence of low birth weight infant in Day 3 group were significantly higher than those in Day 5 group (all P<0.05).The implantation rate in Day 3 fresh group was significantly lower than in Day 5 fresh group (P<0.05).The multiple pregnancy rate,abortion rate,premature birth rate and incidence of lower birth weight in Day 3 fresh group were significantly higher than those in Day 5 fresh group (P<0.05).The clinical pregnancy rate,implantation rate,cesarean section rate,live births rate in group Day 3 frozen-thawed group were significantly lower,but the abortion rate was significantly higher than Day 5 frozen-thawed group (all P<0.05).The clinical pregnancy rate,embryo implantation rate and live birth rate and the male/female ratio at birth in Day 3 fresh embryo group were significantly lower than those in Day 5 frozen-thawed group (all P<0.05).The multiple birth rate,abortion rate,premature delivery rate,cesarean section rate,perinatal mortality rate,fetal malformations rate,low birth weight infant rate in Day 3 fresh group were significantly higher than Day 5 frozen embryo group (all P<0.05).Conclusions:Blastocyst transplantation even transplanting fewer embryos can result in higher implantation rate,clinical pregnancy rate and live birth rate,while reducing multiple birth rate without increasing the risk of overdue birth rate,macrosomia or fetal malformation rate.It may increase male/female ratio at birth,but its long-term impact on the sex ratio still needs further study.