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J Mandelbaum

Publications and source records attributed to J Mandelbaum.

112 records · Page 7Linked to original sources

[Fertility tests (hamster, electronic microscopy): are they useful?].

Tests of sperm function are often considered to be able to predict the in vivo or in vitro fertility of a given patient although they only assess part of the process of sperm fertilizing ability. It appears from the literature, that the sperm penetration assay (SPA) which investigates the sperm fusiogenic and nuclear functions cannot accurately predict the in vivo fertility and there is still much debate on the reliability of its correlation with in vitro fertilization (IVF) principally in cases of severe sperm deficiency. With the development of new techniques of assisted fertilization, by-passing the zona pellucida, a test of sperm fusion, hetero or homospecific as well, could be interesting. Considering sperm ultrastructure and beyond some specific morphological alterations of the whole sperm population that can be responsible for the infertility, such studies were not able, as yet, to reveal significative differences between semen fertile in vitro or not.

Animals↗

[Oocyte maturation and intracytoplasmic sperm injection].

Intracytoplasmic sperm injection (ICSI), treatment of severe male infertility allows an accurate evaluation of oocyte maturity at recovery after corona-cell removal. In cycles comprising a GnRH analog desensitization and a stimulation by hMG or FSH, 12% of oocytes aspirated from follicles (> 14 mm), 34 hours post-hCG are still immature, in prophase or metaphase 1. They are able to achieve meiosis in vitro in 66% of the cases and will be fertilized (2 PN) by ICSI in 51% of the cases as the in vivo mature oocytes of the same cohort. Nevertheless, the quality of cytoplasmic maturation and consequently of embryonic viability remains to be assessed as there still are few pregnancies arising from in vitro matured oocytes. ICSI also represents the only way to obtain normal fertilization in some exceptional but observed anomalies of oocyte maturation, particularly when there is a lack of zona reaction leading to repetitive polyspermy in conventional IVF.

Adult↗

[Are there indications for intra-cytoplasmic sperm injection in female infertility?].

ICSI for oocyte pathology may represent the solution in case of zona pellucida anomalies, deficiency of the oolemma fusion ability or absence of cortical reaction. These indications remain scarce and difficult to be displayed. A link could be shown by some authors between some oocyte morphologic anomalies and IVF fertilization failures which are overcome by ICSI. Other dysmorphic oocytes are associated with an impairment in cytoplasm function which results in a poor embryonic viability on which ICSI has no effect. When few oocytes are recovered (< or = 5) and the semen characteristics are not optimal, ICSI may rectified the decrease in fertilization rates obtained after classical insemination. Lastly, ICSI will become increasingly used in case of oocyte in-vitro maturation or freezing instead of classical IVF which is less efficient.

Female↗