الفهرس 
The OocyteOnly 14 pages are availabe for public view
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Abstract
In the past 50 years, significant advances have been made in understanding the endocrine and intracellular regulation of oocyte maturation.
The in vitro maturation protocol is relatively simple, with a shorter period of treatment. In addition, the side effects are eliminated and costs are reduced compared with conventional in vitro fertilization. In future, immature oocyte retrieval combined with in vitro maturation could possibly replace standard stimulated in vitro fertilization in selected patients.
The aspects of in vitro maturation of human oocytes for fertilization and developmental competence include nuclear and cytoplasmic maturation. The nuclear maturation includes germinal vesicle breakdown, meiotic maturation and chromosome formation.
The following methods are used for oocytes collection: postmortem or post surgical slicing of the ovary, aspiration of the follicles by laparotomy, transvaginal ultrasound-guided follicular aspiration and cryopreserved oocytes.
There are currently four principal scenarios for in vitro maturation technology: in vitro fertilization in women with polycystic ovary, in vitro fertilization in normal women, salvage of immature oocytes for in vitro fertilization and finally in vitro maturation of immature cryopreserved oocytes.
The culture medium for human oocyte in vitro maturation is usually supplemented with serum. The most commonly used protein sources in human oocyte in vitro maturation are fetal cord serum, fetal bovine serum, human serum albumin and synthetic serum substitute.
Previous studies have shown that 80% of immature human oocytes show nuclear maturation and will be at metaphase II by 48- 54 hour in culture medium.
Experiences in vitro maturation have been obtained from two main groups. The first group is women suffering from poly cystic ovarian syndrome. The second group is regular cycling women with normal ovaries referred for in vitro fertilization followed by intracytoplasmic sperm injection due to severe male infertility.
In 1994 the first pregnancy and delivery of a healthy baby after in vitro maturation of immature oocytes obtained in a patient with poly cystic ovarian syndrome. In the following year, another pregnancy was reported in patient with poly cystic ovarian syndrome treated with in vitro maturation, combined with intracytoplasmic sperm injection.
Factors affecting oocyte maturation are gonadotropins, c AMP, maturation promoting factor, growth factor, steroids, calcium, cigarette smoking, age, anesthetic, cryopreservation, culture environment, inhibin B in follicular fluid, oestradiol, inhibin A and epidermal growth factor.
In vitro maturation combined with intracytoplasmic sperm injection using testicular spermatozoa can produce healthy infants, while the normal fertilization rate of in vitro maturation after intracytoplasmic sperm injection using spermatozoa was significantly lower than using the ejaculated spermatozoa.
Research is continuing in optimizing methods for the freezing of isolated immature oocytes and of a complete human ovary. This may have advantages in assisted reproductive technologies and may help to restore fertility in the treatment of cancer in children and young women.
Finally, children born after in vitro maturation are healthy. In vitro maturation of human oocytes achieve high pregnancy rate, safe and effective treatment.