Time-lapse evaluation of human embryo development in single versus sequential culture media--a sibling oocyte study.

Objective: To compare the dynamics of early development between embryos cultured in single and sequential media.

Design: Randomized, comparative study.

Setting: Private IVF centre.

Cryopreservation of blastocysts is the most feasible strategy in good responder patients.

Objective: To assess on which day to cryopreserve and transfer thawed embryos in good-responder patients by comparing the cycle outcomes of day 3 transfers vs blastocysts formed through extended culture before or after cryopreservation.

Design: Retrospective clinical study.

Setting: Private IVF center.

In vitro culture under physiologic oxygen concentration improves blastocyst yield and quality: a prospective randomized survey on sibling oocytes.

A prospective randomized study was carried on sibling oocytes in which human gametes and embryos were cultured at physiologic (6% CO(2) + 5% O(2) + 89% N(2)) condition from insemination to day 6 or at atmospheric (6% CO(2) in air) condition until day 3 and at physiologic environment afterward. The results showed that physiologic oxygen concentration throughout culture period improved total blastocyst yield and day 5 embryo quality.