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the discharge of a secondary oocyte from the graafian follicle; in an adult woman this normally occurs at intervals of about 28 days and alternates between the two ovaries. As a rule, only one secondary oocyte is produced, but occasionally ovulation produces two or more; if more than one subsequently become fertilized, the result may be multiple births, such as twins or triplets. adj., adj ov´ulatory.

Ovulation takes place approximately at the midpoint of the menstrual cycle, 14 days after the onset of menstruation. During the preceding weeks, a graafian follicle (cell cluster in the ovary containing the oocyte) grows from the size of a pinhead to that of a pea. At the moment of ovulation, the follicle bursts open and the ovum is discharged.

The discharged ovum enters the fallopian tube adjoining the ovary and moves toward the uterus; if it encounters a spermatozoon while it is still alive (about 48 hours), the two merge and fertilization takes place, usually in the fallopian tube. The fertilized ovum then makes its way to the uterus, where it becomes embedded in the prepared wall as the first stage of growth of the fetus (see illustration, and see also reproduction). If fertilization does not take place the ovum loses its vitality and the blood and tissue lining the uterus are shed in the menstrual flow.
ovulation method cervical mucus method; see discussion under contraception.


(ov'yū-lā'shŭn, ō'vū-),
Release of an ovum from the ovarian follicle.


/ovu·la·tion/ (ov″u-la´shun) the discharge of a secondary oocyte from a graafian follicle.ov´ulatory


Etymology: L, ovum + atio, process
expulsion of an ovum from the ovary on spontaneous rupture of a mature follicle as a result of cyclic ovarian and pituitary endocrine function. It usually occurs on or about the eleventh to the fourteenth day before the next menstrual period and may cause brief, sharp lower abdominal pain on the side of the ovulating ovary. See also oogenesis. ovulate [ov′yə′lāt] , v.


Release of an oocyte from the ovarian follicle.


The release of an OVUM from a mature Graafian follicle in the OVARY. Ovulation occurs about half way between the beginning of consecutive menstrual periods, usually about 14 days before the expected date of onset of the next period.


the bursting of the OVARIAN FOLLICLE (See also GRAAFIAN FOLLICLE on the surface of the ovary with the release of an egg which then normally passes into the OVIDUCT.


The phase of the female monthly cycle when a developed egg is released from the ovary into the fallopian tube for possible fertilization.


the discharge of the ovum from the graafian follicle.
The discharged ovum enters the uterine tube adjoining the ovary and moves toward the uterus; if it encounters a spermatozoon while it is still alive (about 48 hours), the two merge. Fertilization usually takes place in the uterine tube. The fertilized ovum then makes its way to the uterus, where it becomes embedded in the prepared wall as the first stage of growth of the embryo. See also estrus, estrous cycle.

double ovulation
simultaneous ovulation in both ovaries.
ovulation failure
the ripe follicle does not rupture and discharge its ovum.
ovulation fossa
site of rupture of mature follicles.
multiple ovulation
noncopulatory ovulation
standard procedure in species other than cats.
quiet ovulation
see silent estrus.
ovulation tags
strands of fibrin, proliferating capillaries and leukocytes on the peritoneal serosa close to ovulation sites especially in mares and cows.

Patient discussion about ovulation

Q. i just have my period last november 25 and ended on 28.when is my possible fertile and ovulation period please help me identify my fertile and ovulation period

A. If someone knew it, it'd solve the human race many problems with fertility. The problem is that ovulation (and thus, the period of possible fertility) happens 14 days BEFORE the onset of menses, so you know about it only retrospectively.

However there ways such as serial body temperature measuring, along with kits that measures the level of hormones in the urine in order to estimate the time of the coming ovulation, and help in timing intercourse.

You may read more about it here (www.mayoclinic.com/health/ovulation-signs/AN01521 ) but anyway, consulting a doctor (e.g. gynecologist) may be wise.

More discussions about ovulation
References in periodicals archive ?
racemosa (Klimadynon, Bionorica) in women with PCOS, as assessed through ovulation induction, hormonal profile correction and pregnancy rate.
Table 3 shows the accumulative number of patients with mature follicles >18 mm which was 8; the mean endometrial thickness on the day of ovulation was 8.
Looking at the relative rate of ovulation, there was a 30%-50% improved rate of ovulation if the patient had undergone a preconception lifestyle modification," compared with oral contraceptives alone, said Dr.
By registering with Luna Luna Link provided by MTI, users can get estimations on menstruation and ovulation dates, along with lifestyle advice, etc.
Estrogen, which peaks at ovulation, is a strong candidate, she said.
16SAY NO TO DRUGS Recreational drugs have been found to lower sperm counts and increase abnormal sperm, while female drug users can face ovulation problems.
Judge the validity of an ovulation and pregnancy test and analyze and interpret the results.
Adams' team has known since 2005 that some ingredient in llama semen juices up ovulation, but until now, they didn't know what it was.
The mice with missing insulin receptors, however, maintained near-normal LH levels, regular cycles and normal ovulation despite their obesity.
As Reznik put it, "The effectiveness of Plan B decreases with every passing hour, because the chance of missing [the pill's prevention of] ovulation increases as time passes--and science has demonstrated Plan B doesn't work after ovulation occurs.
If you have sex three days or more before ovulation, the better your chances of conceiving a girl, because the weaker y-sperms tend to die sooner and the x-sperms will be available in greater quantity whenever the egg is released.
There are concerns that induction of ovulation increases the risks of ovarian cancer.