Schlegel P N, Girardi S K
James Buchanan Brady Foundation, Department of Urology, New York Hospital-Cornell Medical Center, New York 10021, USA.
J Clin Endocrinol Metab. 1997 Mar;82(3):709-16. doi: 10.1210/jcem.82.3.3785.
Since the first U.S. report of a successful delivery from in vitro fertilization in 1982 (65), progress in the field of assisted reproduction and micromanipulation has been truly dramatic. Perhaps the most exciting advances have been in the area of male factor infertility. Couples who previously would have been offered donor insemination or adoption are now achieving pregnancies despite severe impairments in semen quality, the presence of only single numbers of sperm in the ejaculate, or unreconstructable reproductive tract obstruction. Techniques of micromanipulation that were revolutionary less than five yr ago are now obsolete, replaced by even more successful methods. Even nonobstructive azoospermia resulting from maturation arrest or other impairments in germ cell development have been added to the list of treatable factors in male infertility, as sperm can frequently be extracted directly from testicular parenchyma that is aspirated or surgically biopsied. For patients without sperm in the testicular parenchyma, round spermatid or secondary spermatocyte injections are at least theoretically possible. Several important questions remain with regard to IVF-ICSI. 1) What should be the specific indications for IVF and IVF-ICSI? Should IVF alone ever be used for male factor infertility? 2) What are the reasons for failure to achieve pregnancy after ICSI, which still represent over half of our attempts at achieving ongoing pregnancies? 3) Can we be certain that using severely impaired or less mature sperm will not result in significant birth defects or in genetic abnormalities that could affect the offspring in adolescence or adulthood? 4) What is the most successful and cost effective approach for the infertile couple with impaired semen parameters? For couples with male factor infertility, careful evaluation and treatment of the man should be considered before assisted reproduction, including ICSI. Contemporary application of ICSI for severe male factor infertility can allow pregnancy rates up to 52% (33), with ongoing pregnancy and live delivery rates as high as 37% per IVF cycle attempt (27). As long as viable sperm are present in the ejaculate or retrievable from the reproductive tract, then ICSI procedures can be applied.
自1982年美国首次报道体外受精成功分娩以来(65),辅助生殖和显微操作领域取得了巨大进展。也许最令人兴奋的进展是在男性因素不育领域。以前只能选择供体人工授精或领养的夫妇,现在即使精液质量严重受损、射精中只有少量精子或生殖道梗阻无法修复,也能成功怀孕。不到五年前还具有革命性的显微操作技术现在已经过时,被更成功的方法所取代。即使是由成熟停滞或生殖细胞发育的其他损伤导致的非梗阻性无精子症,也已被列入男性不育的可治疗因素清单,因为精子通常可以直接从吸出或手术活检的睾丸实质中提取。对于睾丸实质中没有精子的患者,至少从理论上讲,圆形精子细胞或次级精母细胞注射是可行的。关于体外受精-卵胞浆内单精子注射(IVF-ICSI)仍有几个重要问题。1)IVF和IVF-ICSI的具体适应症应该是什么?单独的IVF是否应该用于男性因素不育?2)ICSI后未能怀孕的原因是什么,这仍然占我们实现持续妊娠尝试的一半以上?3)我们能否确定使用严重受损或不太成熟的精子不会导致严重的出生缺陷或影响青少年或成年后代的基因异常?4)对于精液参数受损的不育夫妇,最成功且最具成本效益的方法是什么?对于男性因素不育的夫妇,在进行辅助生殖(包括ICSI)之前,应考虑对男方进行仔细评估和治疗。ICSI在严重男性因素不育中的当代应用可使妊娠率高达%(33),每个IVF周期尝试的持续妊娠和活产率高达37%(27)。只要射精中有活精子或可从生殖道中获取,就可以应用ICSI程序。