The reproductive system of women consists of three organs: the vagina, the uterus and the most important of all the ovaries . The ovaries are the female sex glands that are located symmetrically on each side of the uterus, and are connected to it by the fallopian tubes.
The ovaries play an important role in the life of every woman, since they are responsible for fulfilling the reproductive function and the production of female sex hormones , such as estrogen and progesterone.
When ovulation occurs, the ovaries expel the mature egg into the uterus to allow fertilization of the same by a sperm, to give way to the formation of an embryo that will later become a baby. If the egg is not fertilized then the normal menstrual cycle of each woman known as menstruation will occur.
What is the Importance of the ovaries?
The ovaries are a main component in the human sexual reproduction process. These paired structures, grayish in color and the size of an almond, have as their main task the production of ovules for reproduction.
The ovaries produce estrogen and progesterone, which are the hormones responsible for preparing the uterus to nest the embryo and to express female sexual characteristics at the time of puberty, and they also regulate the menstrual cycle of each woman. These hormones are also responsible for the well-being and health of women, as they affect the physique, body and beauty of their hair.
The ovaries are directly related to the endocrine and immune systems.
Characteristics of the ovaries
The ovaries are two organs whose characteristics are detailed below:
- They are located in the pelvic cavity of the female reproductive system, behind the broad ligaments and against the lateral wall of that cavity.
- Their structures are almond-shaped and elongated.
- The ovaries are small in size and increase in size as the woman develops and reaches adulthood. Generally, healthy ovaries are 3-5 cm long, 2 cm wide and 1 cm thick. They weigh approximately 10 grams.
- The ovary has two main areas which are the medulla and the cortex. The medulla is located in the central region and delivers to the interstitial cells that constitute the theca of the follicles. In the area of the cortex, the follicles are observed in their different stages of development.
- The ovaries are covered with a whitish membrane called the tunica albuginea, and they have small yellowish scars on the surface that correspond to ovulations already completed.
- They are responsible for producing female hormones: Progesterone and Estrogen.
- They have a limited ovarian reserve, since, from birth, we have a defined and non-renewable stock of ovules. The fertility of each woman depends on this stock.
What functions do the ovaries fulfill?
The ovaries have four types of basic functions which are: steroidogenesis, oogenesis, ovulation and fertilization . These two processes are responsible for the proper functioning of the ovulatory cycle, and at the same time they act in the emergence of secondary sexual characteristics in women.
- Steroidogenesis : It is the process that is related to the production of female sex hormones, such as progesterone and estrogen.
- Oogenesis : It is responsible for the formation of oocytes, this is formed in the fetal phase, when several oogonia originate. These cells interfere with their work in the prophase of meiosis (primary oocytes). This fragment again only at puberty, when menstrual cycles start and then ovulation.
- Ovulation : It is the stage where the female germ cell (secondary oocytes) is released, which is the one that is ready to be fertilized. The release of the oocytes happens due to the rupture of the follicle panel. Ovulation occurs in regular pauses in women in the reproductive phase and in the middle of the menstrual cycle, approximately.
- Fertilization: Fertilization occurs when the union of the sperm with the ovum is made, after that, the egg or zygote is formed.
What hormones do the ovaries produce?
Female sex hormones are of two types: Estrogen, also called estradiol, and progesterone . These hormones are secreted by the ovaries according to a cycle, called the menstrual cycle, the manifestation of which is menstruation.
From puberty to menopause, a woman goes through about five hundred cycles, the process of which is only interrupted during pregnancies. During the menstrual cycle, the activity of the ovaries is controlled by two hormones produced by the brain: follicle stimulating hormone (FSH) and luteinizing hormone (LH).
Estrogens are responsible for the development of female organs at the time of puberty: the uterus, breasts and the thickening of the vaginal wall. They also act on the brain, help strengthen bones, feminize the voice and play an important role in the quality of skin and hair. Estrogens are responsible for the distribution of adipose tissue in the hips and thighs, and make women more sensitive to venous problems, such as phlebitis.
Progesterone is produced by the ovaries after ovulation, which is when the egg is released from the ovary. This hormone is responsible for completing and controlling the effects of estrogens. It allows the implantation of the ovum in the uterus and participates in the smooth progress of the pregnancy. It tends to slightly increase a woman’s body temperature.
Structure of the ovaries
There are three types of cells that make up the structure of the ovaries. They are:
The peripheral or superficial layer : it is composed of epithelial cells that have the function of protecting the ovary.
The cubic or germinal epithelium : it is lined with a thin and resistant wall called “the capsule” and it joins the mesovarium, which is a fibrous or albuginea layer, which is underneath. The germ cells or ovarian follicles, which are found within the epithelium, constitute the egg reserves that will be released each month.
The connective tissue or stroma : which constitutes the support tissue of the zygote and guarantees the integrity of the ovary. This deep ovarian layer has two areas:
- The medulla or vascular area: which extends from the ovarian hilum to the center of the ovary and is rich in blood vessels.
- The cortex or parenchymal area: it is a highly vascularized area around the follicles, it is formed by a connective tissue rich in reticular fibers and cells similar to smooth muscle cells.
What is the anatomy of the human ovaries?
These organs, corresponding to the reproductive system of women, come in pairs and surround the uterus one on each side. The ovaries are anchored in the peritoneal cavity through various ligaments which are:
- Ovarian ligament : this ligament is located from the ovary to the uterine body.
- Suspensory ligament: this ligament locates the ovary and is anchored sideways to the pelvic wall.
- Mesovarian: This is immobilized in the middle part. The mesovarian and suspensory ligament establish the part of the broad ligament of the uterus, a fold of the peritoneum that perpetuates a layer over the uterus and that overlies the fallopian tubes, uterus, and vagina. The fibrous ovarian ligament is isolated within the broad ligament.
The ovaries are supported by the ovarian arteries, shunts from the abdominal aorta, and by the ovarian shunts from the uterine arteries. These blood vessels are located in the ovary passing through the suspensory ligaments and the mesovaries.
What are the phases of menstruation in the ovaries?
The simplest process of the menstrual cycle is divided into two phases, which are:
- Estrogenic phase or first phase: corresponds to the first day of menstrual bleeding. This phase represents the predominance of estrogen production. Here the ovum progressively grows and matures in the inner part of the ovary, to be expelled around day 14. This occurs in the middle of the cycle, and is the phenomenon known as ovulation.
- Second phase: When ovulation ends, the other phase begins in which estrogens are decreased and progesterone production increases. The endometrium further develops its thickness and size. The number of blood vessels that supports this increases significantly. On day 25 of the cycle, progesterone declines until day 28, then what we call menstrual flow begins.
What diseases do the ovaries develop?
Unfortunately, like other organs of the body, the ovaries are affected by various pathologies that impair their proper functioning. Among them we can name the following:
- Ovarian cancer: It has been determined that it does not belong to the most common, but it is one of the causes of more deaths, this is due to the difficulties in detecting it.
Warning signs of ovarian cancer:
- Ailment in the lower abdomen.
- Discomfort in the pelvic part.
- Bleeding between menstrual periods.
- Unforeseen weight gain or loss.
- Irregular menstruation.
- Ailment in the lower area of the back.
- Vomiting and nausea
- Ovarian cysts: It is believed that a large number of women suffer from this condition at some point in their lives, they are usually asymptomatic and not very dangerous. The procedure to remove them will depend on the size you have, as well as the age of the woman.
- Polycystic ovarian syndrome: it is an abnormality that occurs when the ovaries cause excessive amounts of male hormones, which creates the development of cysts and various symptoms that can reduce the quality of life of women. This condition creates a risk of diabetes, cardiovascular disease and metabolic syndrome.
- Premature ovarian failure: This failure occurs when the ovaries give up producing eggs, which manifests infertility and hormonal changes.
- Ovarian torsion: It is a condition that suddenly creates severe pain in the lower abdomen, which in many cases spreads to the sides of the back and thighs. It usually affects young women more, however, it can occur at any stage.
Conclusion about the ovaries
The ovaries are the main female reproductive organs, guarantors of the production of hormones and responsible for their sexual characteristics. These hormones help women to have the presence of their menstrual period, it helps them to enjoy beautiful hair, as well as to maintain a good smoothness in the skin.
They also intervene in the production of eggs, so that they can then be fertilized and create the miracle of giving life. Without a doubt, the most important organs of the female reproductive system are the ovaries, since they are precisely what make women different from men.
Dr. Samantha Robson ( CRN: 0510146-5) is a nutritionist and website content reviewer related to her area of expertise. With a postgraduate degree in Nutrition from The University of Arizona, she is a specialist in Sports Nutrition from Oxford University and is also a member of the International Society of Sports Nutrition.