Ovulatory dysfunction is the most common cause of female infertility that occurs in 40% of infertile women.
Anovulation is the lack of ovulation. When ovulation may happen, but irregularly – we are facing the oligoovulation. Anovulation and oligoovulation are different types of ovulatory dysfunction.
What are the causes of ovulatory dysfunction?
Age is the primary factor that negatively affects fertility. With age, ovulation becomes rarer and egg quality degrades. Evaluation of the ovarian reserve allows early detection of premature ovarian failure, premature menopause, or other conditions that adversely affect ovulation.
- Hormonal contraceptives
Hormonal contraceptives such as pills, patches, vaginal rings, and injections suppress ovulation and protect a woman from the unintended pregnancies. Ovulation is restored 2-3 months after discontinuation of most hormonal contraceptives except for so-called depo-preparations, which have a prolonged effect.
- Polycystic Ovarian Syndrome
Polycystic Ovarian Syndrome is characterized by the presence of two or three clinical signs: irregular menstrual cycle which is revealed by delayed periods; excess amounts of androgens (male hormones), which causes excessive hair growth and acne; ultrasound image is showing multiple ovarian inclusion cysts, that do not ovulate. In Polycystic Ovarian Syndrome, carbohydrate metabolism is disturbed, high insulin levels increase the release of androgens, which in turn have a negative effect on ovulation.
Endometriosis is a gynecological pathology, in which the tissue that lines the uterus (the endometrium) grows outside the uterine cavity. During endometriosis, an inflammatory reaction occurs, the quality of the eggs decreases, the ovarian reserve decreases – which adversely affects ovulation.
According to research, there is a close link between fatness and infertility. Overweight disrupts the hormonal balance necessary for a normal menstrual cycle, which can adversely affect ovulation.
Fatness is also associated with insulin resistance and Polycystic Ovarian Syndrome, which is also related to ovulatory dysfunction.
The underweight body also causes ovulatory dysfunction. Ovulation and menstruation require a large amount of energy from the woman’s body. When a woman’s weight is too low, her body tries to save energy by pausing certain functions, such as ovulation.
- Excessive physical activity
Excessive physical exercise (more than 7 hours a week) can cause ovulatory dysfunction in women with normal weight. The reason for infertility caused by excess physical exercise is disorders of secretion of the hormones (GnRH, FSH, LH, and estradiol) involved in the regulation of the reproductive system – which is closely related to ovulatory dysfunction.
- Endocrine disorders
It is well known that disorders of the endocrine system (e.g., the hypothalamus, thyroid gland or pituitary gland disorders) can affect ovulation and other ovarian functions. For example, hyperthyroid or hypofunction of the thyroid gland cause ovulatory dysfunction, menstrual cycle irregularities, and infertility. Excessive secretion of prolactin from the pituitary gland i.e. hyperprolactinemia is also associated with anovulation and infertility.
- Sleep disorders
Sleep disorders (e.g. insomnia) negatively affect a woman’s ovulatory function since sleep regulates the balance of hormones such as thyroid-stimulating hormone, luteinizing hormone (essential for ovulation), follicle-stimulating hormone (important for follicular maturation), progesterone and others. Thus, healthy sleep is important for normal reproductive function.
The blog was prepared by Luda Barbakadze, obstetrician-gynecologist, fertility doctor, Academic Doctor of Medicine, assistant professor at the TSU