Ovulation is the process in female's menstrual cycle by which a mature ovarian follicle ruptures and discharges an ovum intended for fertilization. The time immediately surrounding ovulation is referred to as the ovulatory phase or the periovulatory period. The initiation of ovulation marks the transition from puberty into reproductive maturity for women. From then on, throughout a woman’s reproductive years, ovulation occurs approximately once every 28 days. After ovulation, during the luteal phase, the egg will be available to be fertilized by sperm. In addition, the uterine lining (endometrium) is thickened to be able to receive a fertilized egg. By this time, the oocyte has completed meiosis I, yielding two cells: the larger secondary oocyte that contains all of the cytoplasmic material and a smaller, inactive first polar body. Meiosis II follows at once but will be arrested in the metaphase and will so remain until fertilization. The spindle apparatus of the second meiotic division appears at the time of ovulation. If no conception occurs, the uterine lining as well as blood will be shed during menstruation.
The process of ovulation is controlled by the hypothalamus of the brain and through the release of hormones secreted in the anterior lobe of the pituitary gland, luteinizing hormone (LH) and follicle-stimulating hormone (FSH). In the pre-ovulatory phase of the menstrual cycle, the ovarian follicle will undergo cumulus expansion, which is stimulated by FSH (Pic. 1). Then, ovum will leave the follicle through the formed stigma. Estrogen levels peak towards the end of the follicular phase. This causes a surge in levels of LH and FSH. It lasts from 24 to 36 hours, and results in the rupture of the ovarian follicles, causing the oocyte to be released from the ovary via the oviduct. Several days after ovulation, the increasing amount of estrogen produced by the corpus luteum may cause one or two days of fertile cervical mucus, lower basal body temperatures, or both. This is known as a "secondary estrogen surge".
Induction and suppression
Ovulation induction is a promising assisted reproductive technology for patients with conditions such as polycystic ovary syndrome (PCOS) and oligomenorrhea. It is also used in in vitro fertilization to make the follicles mature before egg retrieval. Usually, ovarian stimulation is used in conjunction with ovulation induction to stimulate the formation of multiple oocytes.
On the other hand, contraception can be achieved by suppressing the ovulation. The majority of hormonal contraceptives and conception boosters focus on the ovulatory phase of the menstrual cycle because it is the most important determinant of fertility. Hormone therapy can positively or negatively interfere with ovulation and can give a sense of cycle control to the female.
The absence of a menstrual period in women of reproductive age.
An eating disorder characterized by the maintenance of a body weight below average, fear of gaining weight, and a distorted body image.
Failure of the ovaries to release an oocyte over a period of time generally exceeding 3 months.
A state in which pieces of the tissue alike to the lining of the uterus (endometrium) grow in other parts of the body.
A hydrosalpinx is an abnormal pouch containing liquid in a fallopian tube.
A medical term which describes a diminished functional activity of the gonads – the testes and ovaries.
The luteinisation of ovulatory follicle without a release of an oocyte.
The time in most women's lives when menstrual periods stop permanently, and the woman is no longer able to have children.
An abnormal condition in a woman's menstrual cycle.
A disease of excess body fat that can have a negative effect on health, leading to reduced life expectancy and other health problems.
Light or infrequent menstrual ﬂow at intervals of 39 days to 6 months or 5–7 cycles in a year.
A form of abdominal adhesions in the pelvis.
A condition in which a woman has an imbalance of female sex hormones. This may lead to changes in the menstrual cycle, cysts in the ovaries, trouble g
The loss of function of the ovaries before age 40.
The type of blockage that affects the part of the fallopian tube end towards the ovary.
The most common benign smooth muscle tumors of the uterus encountered in women of reproductive age.
A physical or psychological condition in which woman cannot engage in any form of vaginal penetration.
FSH is a hormone secreted by the anterior pituitary gland. It regulates the development, growth, pubertal matur and reproductive functions of the body