Details

Autor(en) / Beteiligte

• Feil, Deanne
• Henshaw, Richard C.
• Lane, Michelle

Titel

Day 4 embryo selection is equal to Day 5 using a new embryo scoring system validated in single embryo transfers

Ist Teil von

• Human reproduction (Oxford), 2008-07, Vol.23 (7), p.1505-1510

Ort / Verlag

Oxford: Oxford University Press

Erscheinungsjahr

2008

Quelle

Oxford Journals 2020 Medicine

Beschreibungen/Notizen

• BACKGROUND Single embryo transfers (SETs) require the most viable embryo from a cohort to be selected. Day 4 embryos may provide a selection advantage similar to blastocyst transfer as embryos are replaced post-embryonic genome activation and into the uterus where they would normally reside. However, there is currently no adequate morphological system to assess Day 4 embryos. Therefore, we developed an assessment system for Day 4 embryos and retrospectively assessed Day 4 SET success rates compared with Day 5 SETs. METHODS Embryos (n = 996 after IVF or ICSI) were assessed on Day 4 of development, prior to implementing Day 4 embryo transfers, to obtain a descriptive range of embryo morphologies observed at this time point. A morphological scoring system was developed from this. All patients having an SET after extended culture (Day 4, n = 124 or Day 5, n = 193), at Repromed, Adelaide, Australia, during June 2006–January 2007 were analysed for pregnancy outcome. Ongoing pregnancy was determined by fetal cardiac activity at 6–8 weeks after oocyte collection. RESULTS Day 4 and 5 SETs resulted in similar ongoing pregnancy rates of 38.7% and 32.1%, respectively. CONCLUSIONS A Day 4 scoring system was successfully developed and implemented. Day 4 SETs were found to be a viable option or alternative to Day 5 SETs with no difference in pregnancy rates.