The time interval between laparoscopic tubal ligation and frozen-thawed embryo transfer does not affect the reproductive outcomes

BACKGROUND: Hydrosalpinx may decrease implantation and pregnancy rates after embryo transfer. Laparoscopic tubal ligation after embryo freeze and before frozen-thawed embryo transfer (FET) is effective at improving reproductive outcomes for hydrosalpinx patients. This study is to find out the optimal interval between laparoscopic tubal ligation and FET. METHODS: We retrospectively analyzed 259 infertile women who performed laparoscopic tubal ligation for embryo freeze and FET. Participants were divided into three groups, based on the interval between laparoscopic tubal ligation and FET. Group I: <30 days; Group II: 31– 60 days; Group III: >60 days. Outcomes of cleavage-stage and blastocyst-stage embryo FET were analyzed respectively. RESULTS: There was no significant difference in clinical pregnancy rate, live birth rate, implantation rate, biochemical pregnancy rate, ectopic pregnancy rate, miscarriage rate and preterm birth rate among the three groups, in both cleavage-stage and blastocyst-stage embryo FET cycles. In cleavage-stage embryo FET cycle, singleton gestational age was significantly younger in group III (38.11 ± 2.28 weeks) compared with group I (39.29 ± 1.06 weeks, P = 0.001) and group II (38.96 ± 1.05, P = 0.026). Singleton birth weight was significantly heavier in group II (3.65 ± 0.32 Kg) compared with group I (3.38 ± 0.29 Kg, P = 0.001) and group III (3.35 ± 0.60 Kg, P = 0.004). Twin birth weight was significantly heavier in group III (2.72 ± 0.43 Kg) compared to group I (2.23 ± 0.67 Kg, P = 0.002). In blastocyst-stage embryo FET cycles, twin gestational age was significantly younger in group II (34.07 ± 3.18 weeks) compared with group I (35.56 ± 2.27 weeks, P = 0.049) and group III (36.50 ± 1.47 weeks, P = 0.005). Twin birth weight was significantly heavier in group III (2.71 ± 0.39 Kg) compared to group II (2.39 ± 0.67 Kg, P = 0.009). CONCLUSIONS: The duration of the interval between laparoscopic tubal ligation and FET does not affect the reproductive outcomes; however, it may affect the neonate outcomes to some extent.