Evidence-based outcomes after oocyte cryopreservation for donor oocyte in vitro fertilization and planned oocyte cryopreservation: a guideline.
Level 5 - mechanism / opinion, no new human data
Practice guideline and expert consensus based on a literature search
PubMed 34148587 · doi:10.1016/j.fertnstert.2021.02.024
What was done
The American Society for Reproductive Medicine (ASRM) Practice Committee and an expert task force conducted a systematic literature search of studies published between 1986 and 2018 (including systematic reviews, meta-analyses, randomized controlled trials, and comparative observational studies). From 30 identified studies, the panel developed consensus recommendations assessing clinical pregnancy rates, live birth rates, neonatal outcomes, and prognostic factors across planned autologous oocyte cryopreservation (OC), autologous OC in infertile women, and donor OC.
What was found
The abstract reports no numerical metrics or statistical effect sizes. Qualitatively, it found: - Insufficient evidence exists to reliably predict live birth rates following planned OC. - Limited data suggest ongoing and live birth rates are higher for women undergoing planned OC at a younger age compared with an older age. - Per-transfer pregnancy rates do not differ significantly between cryopreserved and fresh donor oocytes, but evidence is insufficient to prove equivalence in live birth rates. - Neonatal outcomes appear similar between cryopreserved and fresh oocytes across autologous and donor cycles.
Why it matters
This guideline clarifies current clinical evidence, establishing that while oocyte vitrification appears safe regarding neonatal outcomes, reliable predictive models for live birth after planned egg freezing remain lacking.
Limits
The abstract reports no quantitative values, confidence intervals, or sample sizes across the included studies. The guideline highlights critical gaps in the literature, particularly the lack of data on cumulative live birth rates and insufficient evidence demonstrating equivalent live birth rates between vitrified and fresh donor oocytes.
Cited by
- context In the state of California, women over age 42 are legally or clinically restricted to freezing embryos rather than unfertilized eggs.