Related Experiment Video
Updated: Jun 19, 2026

Human Blastocyst Biopsy and Vitrification
Published on: July 26, 2019
First Irish delivery following sequential, two-stage embryo and blastocyst transfer
L H Hayrinen1, E S Sills, A O Fogarty
1Department of Obstetrics and Gynaecology, School of Medicine, Royal College of Surgeons in Ireland, Dublin, Ireland.
Background:
The timing of embryo transfer (ET) after in vitro fertilisation (IVF) remains controversial, and there are no reliable guidelines available to prospectively identify which patients would benefit from either day-3 or blastocyst transfer. While blastocyst transfer is generally favoured over day-3 transfers, very few IVF patients get both in the same treatment cycle.
Case Description:
We report on a 35.5-year-old female with tubal factor infertility who underwent IVF, which included transfer of a fresh day-3 embryo and a thawed blastocyst frozen at day 6. Transfer occurred on two separate days (days 3 and 6) in a two-stage/dual catheter fashion and resulted in a healthy term singleton livebirth.
Conclusions:
While combined day-3 and day-5 ET has been available elsewhere for several years, this is the first description of its successful application in Ireland and confirms the effectiveness of coordinated two-stage transfer in a single IVF treatment cycle.
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