Ultra-rapid versus slow-frozen egg freezing

Title of research: Cryopreserved oocytes – update on clinical applications and success rates

Researchers: Dr Janani Paramanantham, Dr Alon J Talmor, Dr Tiki Osianlis, Dr Gareth C Weston

Abstract

Importance

Over the past 3 decades, oocyte cryopreservation procedures have improved rapidly. However, there is limited research reviewing the efficacy of different cooling protocols and inadequate data comparing in vitro fertilization (IVF) outcomes from fresh oocytes with cryopreserved oocytes.

Objective

The present review was performed to investigate advances in oocyte cryopreservation technologies and identify areas for further research, to determine whether results from IVF using cryopreserved oocytes are comparable to IVF using fresh oocytes, and to identify the patient populations requiring access to oocyte cryopreservation.

Evidence acquisition

A literature review was conducted. OVID (MEDLINE) and PubMed databases were queried using phrases such as “oocyte or egg” and “cryopreservation”, “vitrification”, or “slow cooling or slow freezing”. A total of 180 studies were selected for review.

Results

Current literature suggests that vitrified oocytes produce superior IVF results to slow-frozen oocytes and may yield comparable outcomes to IVF with fresh oocytes in certain patient populations. Patients at risk of infertility due to disease or age-related decline or oocyte donation programs, couples who fail to produce semen when required for IVF, and patients with legal or ethical reasons against embryo cryopreservation may access cryopreserved oocytes.

Conclusions

We suggest that women who comprise the previously mentioned patient populations should be offered oocyte vitrification technology. Further research is required to confirm IVF success across all patient populations and determine the best cryopreservation protocols.

Relevance 

This review will be relevant to clinicians interested in fertility treatments using cryopreserved oocytes, fertility preservation, oncology and fertility, and immunology and fertility.

Reference

Paramanantham J, Talmor AJ, Osianlis T, Weston GC. Cryopreserved oocytes: update on clinical applications and success rates. Obstet Gynecol Surv. 2015; 70(2): 97–114.

Ideal progesterone concentration for an embryo transfer

Title of research: Progesterone concentrations and dosage with frozen embryo transfers – what’s best?

Researchers: Dr Surabhi Kumble Basnayake, Dr Michelle Volovsky, Prof Luk Rombauts, Dr Tiki Osianlis, Prof Beverley Vollenhoven, A/Prof Martin Healey

Abstract

Background

There is a lack of consensus on the optimal dose and form of progesterone supplementation during frozen-thawed embryo transfer with hormone replacement therapy.

Aims

We aim to identify the serum progesterone concentration on day 16 most likely to result in positive pregnancy outcomes.

Materials and methods

We undertook a retrospective study of 4,582 women who underwent frozen embryo transfer with hormone replacement therapy, or natural frozen embryo transfer, over 14 years at a multi-site private in vitro fertilisation clinic. Embryos were 3–5 days of age at the time of transfer. We extracted data on serum progesterone concentrations and outcomes and the dose and form of progesterone supplementation from patient and pharmacy records.

Results

Increased live birth rates for frozen embryo transfer with hormone replacement therapy were seen with day 16 serum progesterone concentrations >50 nmol/L (26.4% vs 11.3% for <50 nmol/L; adjusted odds ratio (OR) 3.14 (95% CI 2.21–4.48)). Similarly, a decreased pregnancy loss rate was seen in this group (14.3% vs 32.6% for ≤50 nmol/L; adjusted OR 0.26 (95% CI 0.12–0.58)). A positive correlation existed between live births and the number of progesterone doses per day (r = 0.119, p = 0.026) and day 16 progesterone concentrations (r = 0.128, p = 0.011).

Conclusion

Improved pregnancy outcomes are seen with day 16 serum progesterone concentrations >50 nmol/L. This study has a statistically significant correlation between live births, number of progesterone doses per day and day 16 serum progesterone concentrations.

Reference

Basnayake SK, Volovsky M, Rombauts L, Osianlis T, Vollenhoven B, Healey M. Progesterone concentrations and dosage with frozen embryo transfers – what’s best? ANZJOG. 2018; 58(5): 533–538.