Is younger better? Donor age less than 25 does not predict more favorable outcomes after in vitro fertilization.

Objective: To determine whether younger oocyte donor age is associated with better outcomes after in vitro fertilization (IVF) compared with older oocyte donor age.

Design: A retrospective cohort study.

Setting: Large academically affiliated infertility treatment center.

DNA methylation dynamics of the human preimplantation embryo.

In mammals, cytosine methylation is predominantly restricted to CpG dinucleotides and stably distributed across the genome, with local, cell-type-specific regulation directed by DNA binding factors. This comparatively static landscape is in marked contrast with the events of fertilization, during which the paternal genome is globally reprogrammed. Paternal genome demethylation includes the majority of CpGs, although methylation remains detectable at several notable features.

Role of increased male age in IVF and egg donation: is sperm DNA fragmentation responsible?

The well documented increase in age that women conceive their first child has detracted from a similar change observed in males. As both males and females decide to conceive later, the question of whether this may impact their fertility individually and as a couple becomes even more crucial. A paternal age of over 40 years at the time of conception is a frequently quoted male age threshold, however, currently there is no clearly accepted definition of advanced paternal age or even a consensus on the implications of advancing male age.