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Ultrasonic Monitoring of Follicular Growth and Ovulation in Spontaneous and Stimulated Cycles
Published in Asim Kurjak, Ultrasound and Infertility, 2020
Some evidence for primary oocyte abnormalities has been given by Liukkonen et al.,45 who have attempted in vitro fertilization in three patients with proven persistent LUF syndrome. By performing follicular puncture they were able to collect only three ova from four treatment cycles. Of three preovulatory oocytes, two were morphologically abnormal, which made their fertilization impossible.
Oocyte retrieval and selection
Published in David K. Gardner, Ariel Weissman, Colin M. Howles, Zeev Shoham, Textbook of Assisted Reproductive Techniques, 2017
Laura F. Rienzi, Filippo M. Ubaldi
It is generally recognized that a “normal” human MII oocyte should have a round, clear ZP, a small PVS containing a single, non-fragmented IPB, and a pale, moderately granular cytoplasm with no inclusions (108,157–162). However, the majority of the oocytes retrieved after ovarian hyperstimulation exhibit one or more morphological abnormalities involving the cytoplasm aspect and/or the extracytoplasmic structures (108,158–163). The actual negative impact of the different oocyte “abnormalities” on IVF and ICSI outcomes is unclear (108, 161, 164). Some authors have suggested that oocytes can be fertilized by ICSI regardless of their morphological appearance (158, 160). Furthermore, embryo quality seems not to be affected by oocyte morphology. Similar clinical pregnancy and implantation rates were also obtained after transferring embryos derived from “abnormal” oocytes as compared with those obtained with embryos derived from “normal”-appearing oocytes (27,158–160,165–168). On the other hand, different authors have reported a correlation between oocyte morphology and embryo developmental potential. Regarding the cumulative effect of multiple morphological features, Xia (159) showed that oocyte grading based on IPB morphology, size of PVS, and cytoplasmic inclusions was correlated with its developmental potential after ICSI. In the study of Chamayou et al. (167), the cumulative effect of morphological features including cytoplasmic texture, inclusions, vacuoles, refractile bodies, and central granulation was found to be related to impaired embryo quality, but did not influence pregnancy rates. A completely different conclusion has been obtained by Serhal and co-authors (169), who found that similar features did not influence in vitro developmental parameters, but implantation and pregnancy rates were lower when embryos were derived from oocytes with cytoplasmic abnormalities. IPB morphology has also been suggested as a possible predictor of oocyte fertilization and embryo quality after ICSI by other authors (30,162,170,171).
Strategies to improve fertilisation rates with assisted conception: a systematic review
Published in Human Fertility, 2018
Yadava Bapurao Jeve, Neelam Potdar, Jane A. Blower, Tarek Gelbaya
If all mature oocytes fail to fertilise, it is called total failed fertilisation (TFF). Total failure of fertilisation may occur due to undetected sperm or oocyte abnormalities (Braude & Rowell, 2003). Sperm-related activation deficiency is seen in globozoospermia and extreme oligoasthenoteratozoospermia (Heindryckx, Van der Elst, De Sutter, & Dhont, 2005). Intracytoplasmic sperm injection (ICSI) has overcome many gamete defects, but total fertilisation failure still occurs in 2–3% of ICSI cycles (Kang et al., 2015; Palermo, Neri, Takeuchi, & Rosenwaks, 2009). Lack of viability, inability of the sperm nucleus to decondense, and chromatin abnormalities can be reasons behind failed fertilisation after ICSI (Nasr-Esfahani, Deemeh, & Tavalaee, 2010). Various sperm function tests are proposed and endorsed by different researchers in addition to the routine semen analysis (Oehninger, Franken, & Ombelet, 2014; Talwar & Hayatnagarkar, 2015). However, sperm function tests are not part of routine fertility investigations as they are complex, expensive, not rigorously tested, do not always provide clinically useful information and typically do not affect treatment outcome (Talwar & Hayatnagarkar, 2015). The most reliable predictor of failed fertilisation is failed fertilisation in the previous IVF cycle (Roest, Van Heusden, Zeilmaker, & Verhoeff, 1998).