Impact of elective frozen vs. fresh embryo transfer strategies on cumulative live birth: Do deleterious effects still exist in normal & hyper responders?

Fazilet Kubra Boynukalin; Niyazi Emre Turgut; Meral Gultomruk; Selen Ecemis; Zalihe Yarkiner; Necati Findikli; Mustafa Bahceci

doi:10.1371/journal.pone.0234481

Impact of elective frozen vs. fresh embryo transfer strategies on cumulative live birth: Do deleterious effects still exist in normal & hyper responders?

PLoS One. 2020 Jun 26;15(6):e0234481. doi: 10.1371/journal.pone.0234481. eCollection 2020.

Authors

Fazilet Kubra Boynukalin¹, Niyazi Emre Turgut¹, Meral Gultomruk², Selen Ecemis¹, Zalihe Yarkiner³, Necati Findikli^{2

4}, Mustafa Bahceci¹

Affiliations

¹ Department of Reproductive Endocrinology and IVF Center, Bahceci Health Group, Istanbul, Turkey.
² Department of Embryology and R&D Center, Bahceci Health Group, Istanbul, Turkey.
³ Cyprus Science University, Kyrenia, Cyprus.
⁴ Department of Biomedical Engineering, Beykent University, Istanbul, Turkey.

Abstract

Background: Is freeze-all strategy effective in terms of cumulative live birth rates (CLBRs) in all patients?

Methods: This retrospective single-center study analyzed the CLBRs of 2523 patients undergoing fresh or electively frozen blastocyst transfer cycles. In 1047, cycles, the fresh embryo transfer (ET) strategy was applied for the 1st ET, whereas electively frozen ET (e-FET) was performed in 1476 cycles. Female age ≤ 37 and blastocysts frozen via vitrification were included. The patients in each arm were further stratified into four subgroups according to the number of oocytes retrieved as follows: Group A: 1-5, group B: 6-10, group C: 11-15 and group D: 16-25 oocytes retrieved. The primary endpoint was the CLBR. The secondary endpoints were the ovarian hyperstimulation syndrome (OHSS) rate and the live birth rates (LBRs) following fresh ETs and e-FETs for the first transfers.

Result(s): The CLBR was similar between the fresh ET and e-FET arms in group A (35/76 (46.1%) vs 29/67 (43.3%), p = 0.74) and group B (165/275 (60%) vs 216/324 (66.7%), p = 0.091), whereas significantly higher rates were detected in favor of the e-FET arm within group C (328/460 (71.3%) vs 201/348 (57.8%), p<0.001) and group D (227/348 (65.2%), vs 446/625 (71.5%), p<0.001). The OHSS rate was also found to be higher in the fresh ET arm among group C (12/348 (3.4%) vs 0/460 (0%), p<0.001) and group D (38/348 (10.9%) vs 3/625 (0.5%), p<0.001) patients than e-FET arm. Perinatal and obstetrical outcomes were nonsignificantly different between fresh and e-FET arms. However, the birth weights were significantly lower for fresh ET, 3064 versus 3201 g for singletons (p<0.001).

Conclusion: Compared with a fresh-transfer strategy, the e-FET strategy resulted in a higher CLBR among patients with >10 oocytes retrieved during stimulated cycles.

Publication types

Comparative Study
Research Support, Non-U.S. Gov't

MeSH terms

Adult
Cryopreservation*
Embryo Transfer / methods*
Female
Fertilization in Vitro / methods*
Humans
Live Birth / epidemiology*
Oocyte Retrieval / statistics & numerical data*
Ovarian Hyperstimulation Syndrome / epidemiology
Retrospective Studies
Specimen Handling / methods*

Associated data

figshare/10.6084/m9.figshare.12236423

Grants and funding

Bahceci Health Group provided support in the form of salaries for FKB, NET, x0MG, SE, NF and MB. Cyprus Science University provided support in the form of salaries for author ZY. The specific roles of these authors are articulated in the ‘author contributions’ section. No financial support in the form of a grant, salary or a gift have been received from the funders solely for the current study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.