Does sperm origin affect embryo morphokinetic parameters?by Jenna Lammers, Arnaud Reignier, Carole Splingart, Aurore Catteau, Laurent David, Paul Barriere, Thomas Freour

Journal of Assisted Reproduction and Genetics

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GAMETE BIOLOGY

Does sperm origin affect embryo morphokinetic parameters?

Jenna Lammers1,2,6 & Arnaud Reignier1,2,5,6 & Carole Splingart1,2,6 & Aurore Catteau1 &

Laurent David2,3,4,5,6 & Paul Barriere1,2,5,6 & Thomas Freour1,2,5,6,7

Received: 11 March 2015 /Accepted: 15 June 2015 # Springer Science+Business Media New York 2015

Abstract

Purpose The purpose of our study was to use time-lapse in order to evaluate the impact of sperm origin (fresh ejaculate or surgically retrieved) on embryo morphokinetic parameters and clinical outcome in intracytoplasmic sperm injection (ICSI) cycles.

Methods This retrospective monocentric study was conducted in 485 unselected couples undergoing 604 ICSI cycles with embryo culture in the Embryoscope®.

Among them, 445 couples underwent ICSI cycle with fresh ejaculated sperm and 40 with surgically retrieved sperm (26 with testicular sperm and 14 with epididymal sperm). Embryo morphokinetic parameters and clinical cycle outcome were compared between fresh ejaculated sperm and surgically retrieved sperm. A subgroup analysis was also conducted between testicular and epididymal sperm ICSI cycles.

Results Clinical outcome was comparable between groups according to sperm origin. Although most early morphokinetic parameters were comparable between ejaculated and surgical sperm groups, a few parameters were significantly different between both groups, but with a considerable overlap in their distribution. Late cellular events occurred significantly later in the surgical sperm group than in the ejaculated sperm group.

Conclusions Morphokinetic analysis did not allow us to identify clinically relevant differences between fresh ejaculate and surgically retrieved sperm groups. Further studies are needed, especially concerning the relationship between sperm origin and late morphokinetic parameters, such as blastocyst development.

Keywords Time-lapse .Morphokinetic . ICSI .

Azoospermia . Surgically retrieved sperm

Introduction

The first technical revolution in terms of assisted reproductive technology (ART) after the first IVF cycle was pioneered in the late 1970s [1] consisted of intracytoplasmic sperm injection (ICSI) in the 1990s, allowing the numerous couples suffering from male infertility to seek IVF at last. Thanks to the implementation of ICSI, embryologists have progressively been able to treat patients with severe oligospermia or even azoospermia when surgical sperm retrieval could be attempted with success. Indeed, microepididymal sperm aspiration (MESA) can be attempted in cases of obstructive azoospermia (OA) with very high success rates (>90 %), and testicular sperm extraction (TESE) can be attempted in non-obstructive azoospermia (NOA) cases, albeit with lower success rates [2].

Capsule Time-lapse parameters do not significantly differ according to sperm origin * Thomas Freour thomas.freour@chu-nantes.fr 1 Service de Médecine et Biologie de la Reproduction, CHU de

Nantes, Nantes 44093, France 2 INSERM UMR 1064, ITERT, Nantes, France 3 INSERM UMS 016, SFR Santé, iPSC Core Facility, Nantes, France 4 CNRS UMS 3556, SFR Santé, iPS Core Facility, Nantes, France 5 UFR Médecine, Université de Nantes, Nantes, France 6 ITUN, CHU Nantes, Nantes, France 7 Clínica EUGIN, 08029 Barcelona, Spain

J Assist Reprod Genet

DOI 10.1007/s10815-015-0517-z

Although many studies have reported acceptable pregnancy rates in ICSI cycles with surgically retrieved sperm [3], very few data are available on the influence of sperm origin, i.e., ejaculated or surgically retrieved sperm, on early embryo development [4–6]. Moreover, all data are based on conventional embryo quality assessment with morphology, this technique being known to suffer from moderate sensitivity, moderate specificity [7], and inter/intra-observer variability [8].

The recent introduction of time-lapse monitoring (TLM) systems, providing stable incubation conditions and continuous follow-up of embryo development with exact measurement of all cleavage timings, has begun a new era in the field of embryology, allowing the implementation of a more accurate and reproducible embryo quality assessment method based on morphokinetics [9, 10]. TLM can thus be used to compare embryo development in ICSI cycles in terms of sperm origin more accurately than conventional morphology. As clinical implementation of TLM is based on the use of precise kinetic parameters combined into algorithms, it is important to identify any clinical or demographic factors that might significantly impact on morphokinetic parameters, in order to take them into account and control them.

The aim of our study was therefore to compare the morphokinetic aspects of early embryo development in ICSI cycles according to sperm origin, i.e., fresh ejaculated (FES) or surgically retrieved sperm (SRS).

Material and methods

We retrospectively analyzed the data of consecutive patients who had undergone IVF-ICSI with oocyte and embryo cultures performed with the Embryoscope®.

These data were collected and recorded in a registered authorized database between February 2011 and October 2013 in our IVF unit. All the patients gave written informed consent to the procedures and to the digital recording and anonymous use of the data related to their history (IRB-approved procedure). Only ICSI cycles were included to determine as precisely as possible the timing of fertilization. All information on implantation, viable pregnancy occurrence, delivery, and early postnatal complications was available at the time of analysis.

A male factor was identified in all cycles, i.e., abnormal sperm analysis was performed strictly in accordance with

WHO criteria (5th edition) [11]. When live sperm were present in the ejaculate, sperm preparation was performed on silica gradient (two layers, 90 and 50 %, Suprasperm®,

Origio®). Azoospermia was diagnosed when no spermatozoa could be observed after centrifugation of two consecutive sperm analyses. NOA or OA diagnosis was based on medical history, physical examination, hormonal status, genetic workup, and testicular volume. In NOA cases, TESE was performed with the open biopsy procedure. Testicular tissue was gently crushed in order to extract living spermatozoa. The cellular suspension was loaded onto 40 % silica suspension (Suprasperm®, Origio, France) and centrifuged at 2000 rpm for 15 min. Live spermatozoa found in the pellet (testicular sperm (TS)) within the silica layer and/or in the supernatant were resuspended in Universal IVF medium® (Origio®) and frozen in liquid nitrogen according to the standard slow freezing method until thawing, when the