PURPOSE: To compare the incidence of monozygotic twins following blastocyst versus day-3 embryo transfer (ET). METHODS: A retrospective analysis of the outcome of assisted reproductive technology (ART) cycles utilizing blastocyst ET during 1999-2000 was compared to a similar group of patients undergoing day-3 ET during 1997-1998. RESULTS: Blastocyst ET was used in 75 cycles with 2.0 +/- 2 embryos transferred. The comparison group consisted of 90 cycles with day-3 ET and 3.0 +/- 2 embryos transferred. CONCLUSIONS: High pregnancy rates are maintained with blastocyst ET even though fewer embryos are transferred. The rate of monozygotic twins is higher with blastocyst ET than with day-3 ET. This increase may partially negate the benefit of reduced high-order multiple gestations attributed to blastocyst ET.
PURPOSE: To compare the incidence of monozygotic twins following blastocyst versus day-3 embryo transfer (ET). METHODS: A retrospective analysis of the outcome of assisted reproductive technology (ART) cycles utilizing blastocyst ET during 1999-2000 was compared to a similar group of patients undergoing day-3 ET during 1997-1998. RESULTS: Blastocyst ET was used in 75 cycles with 2.0 +/- 2 embryos transferred. The comparison group consisted of 90 cycles with day-3 ET and 3.0 +/- 2 embryos transferred. CONCLUSIONS: High pregnancy rates are maintained with blastocyst ET even though fewer embryos are transferred. The rate of monozygotic twins is higher with blastocyst ET than with day-3 ET. This increase may partially negate the benefit of reduced high-order multiple gestations attributed to blastocyst ET.
Authors: A L da Costa AL; S Abdelmassih; F G de Oliveira ; V Abdelmassih; R Abdelmassih; Z P Nagy; J P Balmaceda Journal: Hum Reprod Date: 2001-02 Impact factor: 6.918
Authors: Richard J Paulson; Robert Boostanfar; Peyman Saadat; Eliran Mor; David E Tourgeman; Cristin C Slater; Mary M Francis; John K Jain Journal: JAMA Date: 2002-11-13 Impact factor: 56.272