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Frozen Embryos Beat Fresh Ones for IVF

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Women undergoing IVF who have had embryos fail to implant are almost twice as successful using frozen ones than fresh ones, according to a study published in The Australian and New Zealand Journal of Obstetrics and Gynaecology (

The study followed 84 patients who underwent 140 IVF cycles to identify success rates by comparing the two different types of transfers (frozen versus fresh) with recurring unsuccessful cycles. “We found the birth rate for frozen and thawed embryos was 39%, compared to 20% for fresh embryos,” said Prof Roger Hart of the University of Western Australia’s Division of Obstetrics and Gynaecology.

The study excluded any correctable factors present within the woman that may have limited the embryo implanting, and then undertook preimplantation genetic screening of embryos on the third day to ensure there were no abnormalities. “We examined the chromosomal status of the embryo, as unfortunately the most common reason an embryo does not implant is because it is chromosomally abnormal,” Hart said.

“The study results demonstrate that a frozen embryo implantation is more successful than transferring the embryo straight after the biopsy in a fresh IVF cycle, as the environment within the uterus is more ‘normal’ in a subsequent natural cycle than during...

The full text of this article can be purchased from Informit.