Ads
related to: oocytes during pregnancy test normal range by age chart for men
Search results
Results From The WOW.Com Content Network
An oocyte (/ ˈ oʊ ə s aɪ t /, oöcyte, or ovocyte is a female gametocyte or germ cell involved in reproduction.In other words, it is an immature ovum, or egg cell.An oocyte is produced in a female fetus in the ovary during female gametogenesis.
Ovum quality is the measure of the ability of an oocyte (the female gamete) to achieve successful fertilisation.The quality is determined by the maturity of the oocyte and the cells that it comprises, which are susceptible to various factors which impact quality and thus reproductive success. [1]
Ageing predominantly affects oocytes during their arrest in the prophase of meiosis I – where genetic stability is often undermined. [10] The principal oocyte abnormality associated with increased maternal age is aneuploidy, in which chromosome segregation errors result in oocytes having the wrong number of chromosomes. [9]
Approximately 1–2% of ovulations release more than one oocyte. This tendency increases with maternal age. Fertilization of two different oocytes by two different spermatozoa results in fraternal twins. [10] The precise moment of ovulation was captured on film for the first time in 2008, coincidentally, during a routine hysterectomy procedure.
Statistical analysis showed that the women in the 27–29 age group had significantly less chance on average of becoming pregnant than did the 19- to 26-year-olds. Pregnancy rates did not change notably between the 27–29 age group and the 30–34 age group, but dropped significantly for the 35–39 age group. [14]
At puberty, the number of oocytes decreases even more to reach about 60,000 to 80,000 per ovary, and only about 500 mature oocytes will be produced during a woman's life, the others will undergo atresia (degeneration). [12]
References range may vary with age, sex, race, pregnancy, [10] diet, use of prescribed or herbal drugs and stress. Reference ranges often depend on the analytical method used, for reasons such as inaccuracy, lack of standardisation, lack of certified reference material and differing antibody reactivity. [11]
When the fetus has developed to a certain point, pregnancy is concluded with childbirth, involving labor. During labor, the uterine muscles contract, and the cervix dilates typically over a period of hours, allowing the infant to pass from the uterus through the vagina. [1]