| Autor: |
Hammond ER; Fertility Associates, 7 Ellerslie Racecourse Drive, Remuera, Auckland 1051, New Zealand., Cree LM; Fertility Associates, 7 Ellerslie Racecourse Drive, Remuera, Auckland 1051, New Zealand.; Department of Obstetrics and Gynaecology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd, Grafton, Auckland 1023, New Zealand., Morbeck DE; Fertility Associates, 7 Ellerslie Racecourse Drive, Remuera, Auckland 1051, New Zealand.; Department of Obstetrics and Gynaecology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd, Grafton, Auckland 1023, New Zealand. |
| Abstrakt: |
Extended culture to the blastocyst stage is widely practised, improving embryo selection and promoting single embryo transfer. Selection of useable blastocysts typically occurs on Days 5 and 6 of embryo culture. Embryos not suitable for transfer, biopsy or cryopreservation after Day 6 are routinely discarded. Some embryos develop at a slower rate, however, forming blastocysts on Day 7 of culture. Day 7 blastocysts can be viable, they can be of top morphological grade, euploid and result in a healthy live birth. Since ending culture on Day 6 is current practice in most clinics, viable Day 7 blastocysts may be prematurely discarded. Although Day 7 blastocysts make up only 5% of useable blastocysts, those which are suitable for cryopreservation or biopsy are clinically significant. Overall, culturing embryos an additional day increases the number of useable embryos per IVF cycle and provides further opportunity for pregnancy for patients, especially those who have only a few or low-quality blastocysts. |
