title: Early pregnancy loss is significantly higher after day 3 single embryo transfer than after day 5 single blastocyst transfer in GnRH antagonist stimulated IVF cycles.
abstract: The current study aimed to investigate whether single day-3 embryo transfer (SET) results in higher early pregnancy loss (EPL) than single blastocyst transfer (SBET). A total of 896 patients underwent 1103 IVF cycles with a gonadotrophin-releasing hormone (GnRH) antagonist protocol. In 603 cycles (D3 group) a single embryo on day 3 of the embryo culture was transferred, whereas in the remaining 500 cycles a single blastocyst was transferred on day 5 (D5 group). Multifollicular ovarian stimulation was performed with a GnRH antagonist protocol starting on day 6. SET resulted in 209 pregnancies (34.7%), compared with 221 pregnancies (44.2%) for SBET. Early pregnancy loss rate was significantly higher with SET compared with SBET (26.8% versus 17.2%, P = 0.017) and ongoing implantation rate was also significantly higher with day 5 compared with day-3 embryo transfer (OR:1.68, 95% confidence interval:1.31-2.18). Sub-optimal embryo selection for transfer on day 3, in addition to asynchronization between altered endometrium and early exposure of cleavage-stage embryos, might explain the above difference. Nevertheless, the higher implantation potential of the blastocyst questions the rationale behind performing single embryo transfer on day 3 of embryo culture in women under 36 years old.
authors.affiliation: Centre for Reproductive Medicine, University Hospital, Vrije Universtiteit Brussel (Dutch-Speaking Brussels Free University), Laarbeeklaaan 101, B-1090, Brussels, Belgium. Evangelos.Papanikolaou@vub.ac.be
authors.forename: E G
authors.initials: EG
authors.lastname: Papanikolaou
authors.forename: M
authors.initials: M
authors.lastname: Camus
authors.forename: H M
authors.initials: HM
authors.lastname: Fatemi
authors.forename: H
authors.initials: H
authors.lastname: Tournaye
authors.forename: G
authors.initials: G
authors.lastname: Verheyen
authors.forename: Andre
authors.initials: A
authors.lastname: Van Steirteghem
authors.forename: Paul
authors.initials: P
authors.lastname: Devroey
mesh_terms: D000328:Adult; D001755:Blastocyst / Q000502:physiology*; D046149:Embryo Culture Techniques; D004624:Embryo Transfer; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000037:antagonists & inhibitors*; D006062:Gonadotropins / Q000494:pharmacology*; D006801:Humans; D010062:Ovulation Induction / Q000379:methods; D011247:Pregnancy; D011256:Pregnancy Outcome; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods*; D013997:Time Factors
chemical_list: D006062:Gonadotropins; D007987:Gonadotropin-Releasing Hormone