Graham M C, Hoeger K M, Phipps W R
Department of Obstetrics-Gynecology, University of Rochester, Rochester, New York 14642, USA.
Fertil Steril. 2000 Oct;74(4):668-71. doi: 10.1016/s0015-0282(00)01528-4.
To report our initial IVF-ET experience combining assisted hatching performed 3 days after oocyte retrieval with day 5 embryo transfer (ET).
Retrospective review of 110 consecutive IVF cycles not involving donor oocytes, including 16 cycles that involved assisted hatching performed 3 days after oocyte retrieval in combination with day 5 ET.
Academic teaching hospital IVF center.
PATIENT(S): Eighty-six consecutive IVF patients undergoing ET.
INTERVENTION(S): Assisted hatching using acid Tyrode's solution performed 3 days after oocyte retrieval in selected cases in combination with day 3 or 5 ETs.
MAIN OUTCOME MEASURE(S): Clinical pregnancy rate per ET.
RESULT(S): Of the 16 women undergoing day 5 ET following day 3 assisted hatching, 14 had a clinical pregnancy. These included 11 ongoing/delivered singletons and 2 ongoing/delivered twin pregnancies, neither of which was monochorionic. These clinical and ongoing/delivered pregnancy rates compared very favorably with those of 54% and 46%, respectively, for the 35 patients undergoing day 5 ETs without assisted hatching, even though the latter group appeared to be better IVF candidates based on the prognostic factors commonly used to predict success.
CONCLUSION(S): Our experience suggests that day 3 assisted hatching followed by day 5 ET may be a useful combination in selected patients. Although not seen in our small series, an increased risk of monochorionic pregnancies remains a theoretical concern when such a combination is used, since both assisted hatching and blastocyst transfers have been independently linked to an increased risk in some reports.
