P-057 Does sperm cryopreservation affect the clinical outcome? A retrospective study in an oocyte donation program
Authors: Pantopikou K , Oraiopoulou C , Papatheodorou A , Drakopoulos P , Christoforidis N , Chatsiparasidou A 
Published: June 2023

Abstract

Study question
Does sperm cryopreservation have a negative impact on pregnancy and live birth rate (LBR)?

Summary answer
The use of frozen sperm does not affect pregnancy rates and LBR significantly compared to fresh sperm.

What is known already
The use of frozen sperm, especially in oocyte donation cycles, is a common strategy in organizing a couple’s treatment. By now, contradictory data has been published concerning the impact of fresh sperm versus frozen on pregnancy and LBR. There is data indicating reduction of the LBR with the use of frozen sperm in a donation program, while in other studies no significant difference between fresh and frozen sperm was observed in the LBR.

Study design, size, duration
This is a retrospective cohort study conducted in Embryolab Fertility Clinic, Greece, from January 2019 to March 2020. Only oocyte donation cycles were included in the study. On the day of donor's oocyte retrieval ICSI was performed, either with fresh (group A) or frozen sperm (group B)All embryos were cultured to blastocyst stage, assessed for their development, vitrified and two were transferred post warming on a subsequent HRT cycle.

Participants/materials, setting, methods
For the present study, 135 cases were analyzed: in 28 cases fresh sperm was used, while frozen sperm was used in 107 cases[pd1] . The mean men’s age was 44.4 years, while all oocyte-donors were below 35 years old. The main outcome measure was LBR, while fertilization rate, blastulation rate as well as positive β-HCG were also analyzed. All patients with uterine factor, severe male factor or surgically obtained sperm were excluded from the study.

Main results and the role of chance
There was no significant difference between LBR of fresh vs frozen sperm (53.57% ±50.78 vs 50.47% ±50.23, p=0.086). Although positive β-CG reached a higher percentage in fresh sperm samples, there was no significant difference between two groups (85.71% ±35.63 in fresh vs 77.78% ±41.76 in frozen sperm, p=0.857). Similarly, both blastulation rate (68.93% ±25.22 in fresh vs 67.97% ± 28.72 in frozen sperm, p=0.873) and fertilization rate (85.36% ±16.92 in fresh vs 83.27% ±17.01 in frozen sperm, p=0.565) did not differ significantly between fresh and frozen sperm samples. [pd1] Regression analysis adjusting for relevant confounders (endometrial thickness the day of the embryo transfer, BMI, donor’s age) showed no association between LBR and sperm type (fresh vs cryopreserved).

Limitations, reasons for caution
This is a retrospective study, including sperm samples irrespectively to quality parameters (sperm count, motility, morphology). The number of previous treatments per couple was not included in the study.

Wider implications of the findings
The outcome of the study indicates that the use of frozen sperm is a viable choice in a donation program, as it does not induce any negative effects in LBR. However, specific subgroups might benefit from fresh sperm especially when the sperm parameters are low.

Trial registration number
N/A