Cumulative Live Birth Rates After Cleavage-stage Versus Blastocyst-stage Embryo Transfer
Condition: Infertility
MeSH terms: Infertility
Study type: Interventional

Summary: 
      The aim of this RCT is to compare differences in the efficacy and safety between
      cleavage-stage embryo transfer and blastocyst-stage embryo transfer in IVF/ICSI treatment
      cycle, taking into account of subsequent vitrified embryo transfers. Subjects with 3 or more
      transferrable cleavage embryos will be randomized to the cleavage-stage or blastocyst-stage
      embryos transfer group. The primary outcome is cumulative live birth rate (CLBR) per patient
      until the first live birth from one initiated oocyte retrieval cycle, calculated using
      outcomes from the first three embryo transfers within 1 year after randomization.
    

Detailed description: 
      This is a multicenter, randomized clinical trial comparing the efficacy and safety between
      cleavage-stage embryo transfer and blastocyst-stage embryo transfer in IVF/ICSI treatment
      cycle, taking into account of subsequent vitrified embryo transfers.Randomization will be
      performed on day 2/3 after oocyte retrieval, when at least 3 embryos are achieved. Patients
      in group A will have 1 cleavage-stage embryo transferred. Patients in group B will have 1
      blastocyst-stage embryo transferred. The outcomes from all the embryo transfers within 1 year
      after randomization will be followed up. If a pregnancy/live birth is not achieved, single
      embryo transfer is required for the first 3 embryo transfers within 1 year after
      randomization. For embryo transfers beyond the third within the 1 year, patient's treatment
      must follow their randomized allocation, and SET is no longer mandatory. The follow-up period
      is 2 years from the day of randomization.Due to the COVID-19 pandemic, the participants who
      were unable to undergo the embryo transfers in 1 year of randomization will have 3 months
      extension for frozen embryo transfer. The follow-up for these participants will be extended
      for 3 months as well.
    

Intervention name(s): blastocyst-stage embryo transfer; cleavage-stage embryo transfer
Intervention type(s): Procedure; Procedure
Intervention description(s): All the participants will receive a long GnRH-agonist, ultra-long GnRH-agonist, short GnRH-agonist or GnRH antagonist protocol in combination with recombinant FSH. HCG will be administered for final oocyte maturation. Patients will have a single blastocyst-stage embryos transferred. The outcomes of all the embryo transfers within 1 year after randomization will be followed up. Single embryo transfer (SET) is required for the first 3 embryo transfers within 1 year after randomization. For embryo transfers beyond the third within the 1 year, patients' treatment must follow their randomized allocation, and SET is no longer mandatory. Luteal phase support will be administered before embryo transfer. If pregnancy is confirmed, luteal phase support will be continued until 10 weeks of gestation. The follow up will be continued until 6 weeks after delivery.; All the participants will receive a long GnRH-agonist, ultra-long GnRH-agonist, short GnRH-agonist or GnRH antagonist protocol in combination with recombinant FSH. HCG will be administered for final oocyte maturation. Patients will have a single cleavage-stage embryos transferred. The outcomes of all the embryo transfers within 1 year after randomization will be followed up. Single embryo transfer (SET) is required for the first 3 embryo transfers within 1 year after randomization. For embryo transfers beyond the third within the 1 year, patients' treatment must follow their randomized allocation, and SET is no longer mandatory. Luteal phase support will be administered before embryo transfer. If pregnancy is confirmed, luteal phase support will be continued until 10 weeks of gestation. The follow up will be continued until 6 weeks after delivery.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Cumulative live birth rates; cleavage-stage embryo transfer; blastocyst transfer