Conventional IVF improves blastocyst rate and quality compared to ICSI when used in patients with mild or moderate teratozoospermia

Abstract

The ICSI procedure was invented to treat severe male infertility but is often used even if the sperm quality parameters are normal. This practice has recently been called into question, but there is still no clear answer especially in terms of sperm morphology, regarding when it is necessary to perform ICSI and when conventional IVF is indeed more beneficial. In borderline cases it seems logical to fertilize oocytes using ICSI and conventional IVF at the same time. Since we also use this approach we performed a retrospective analysis of such cycles to elucidate, which procedure results in a better clinical outcome in terms of fertilization rate, the quality of day 3 and day 5 embryos, and the pregnancy rate. The data from fifty-one couples who were treated with ART and whose male factor of infertility was defined as teratozoospermia were included. The fertilization rates were similar between ICSI and conventional IVF groups (per COCs: 54.5% vs. 58.2%, P = 0.322; per MII oocytes: 63.9% vs. 67.2%; P = 0.399), but more oocytes degenerated after ICSI (11.7% vs. 4.3%; P = 0.0003). The quality of cleaved embryos was similar between the groups, but more embryos reached the blastocyst stage after conventional IVF (43.7% vs. 55.0%; P = 0.032) and furthermore, more of them were of good quality (19.8% vs. 29.2%; P = 0.037). The pregnancy rate did not significantly differ between the groups (21.4% vs. 45.5%; P = 0.175), although there was a trend in favor of conventional IVF. This retrospective analysis suggests that when sperm morphology is not severely impaired and sperm concentration and motility are normal, it is better to use conventional IVF to fertilize oocytes and not ICSI. The main advantage of conventional IVF is reflected in improved blastocyst rate and quality.

More blastocysts are produced from fewer oocytes in ICSI compared to IVF – results from a sibling oocytes study and definition of a new key performance indicator

“…In concordance with our results analyzed in their globality and by sub-groups, previous authors applying split insemination found significant higher fertilization rate in ICSI compared to IVF [ 11 , 15 – 17 , 28 ], comparable cleavage rate [ 10 – 12 , 14 , 15 , 20 ], no statistical difference in blastocyst rate [ 11 , 13 ], comparable implantation [ 10 , 12 ] and live birth rates [ 13 , 16 ].…”

“…Previous authors applying split insemination reported data from embryo development until cleavage stage [ 10 , 12 , 15 , 16 ] or on a minor number of cases [ 11 , 13 , 14 , 18 , 28 ]. The present study is the first one focused mainly on blastocyst stage, and on such a high number of cases that could also be analyzed according to different clinical parameters.…”

“…The Key Performance Indicators (KPIs) applied to compare the two fertilization methods were fertilization and cleavage rates, embryo quality, the percentage of transferred and frozen embryos on zygote number, and clinical outcome measurements such as implantation and clinical pregnancy rates. Different studies found the two fertilization methods comparable and suggest applying IVF when possible [12][13][14] even when the fertilization rate was higher in ICSI [11,[15][16][17]. In all cases, the authors tested the goodness of IVF and ICSI procedures in their lab from a technical perspective.…”

Retrospective study of rescue intra cytoplasmic sperm injection (ICSI) as an emergency procedure aimed at salvaging the IVF ET cycle

“…This heralds the onset of flux in cytoplasmic calcium and cascade of fertilization. Numerous authors support use of conventional IVF to improve embryo quality and quantity in non-severe male factor [17] . Implantation rate, clinical and live delivered pregnancy rate were significantly higher in conventional IVF group.…”

Reactive oxygen species in reproduction: harmful, essential or both?

“…Conventional IVF is known as an effective technique for fertilization and successful embryo development in case of non-male infertility factors. Several studies have shown that conventional IVF is a better approach than ICSI when sperm concentration, motility and morphology are normal (Bhattacharya et al, 2001;Gennarelli et al, 2019;Stimpfel et al, 2019). During the conventional IVF process, ROS can originate from dead spermatozoa and white blood cells of sperm.…”