The term sterility (infertility) refers to the inability to get pregnant when trying for 12 months in women up to 35 years of age or for 6 months in patients over 35 years of age. The etiology of infertility is diverse, with ovarian pathology and fallopian tube pathology playing a leading role. Sterility can be divided into two types: primary – inability to conceive in the absence of a previous pregnancy, and secondary – inability to conceive in the case of previous childbirth, abortion or ectopic pregnancy. In Bulgaria, about 200,000 families suffer from sterility, which is why diagnosing the cause of infertility and applying the right therapy are of utmost importance for a faster solution to the problem and the realization of the dream of a child. There are many methods for the diagnosis of infertility, and the complex evaluation of the obtained results is of fundamental importance for making the correct diagnosis. Although we are focused on infertility in women, when specifying the cause of infertility, the male factor should not be excluded, and tests should also be assigned to the man of the couple, the most banal of which is the spermogram. After unsuccessful attempts to conceive within the described period, the couple should visit a reproductive specialist. The diagnosis of infertility in a woman begins with taking a detailed gynecological history. It is important to study the regularity of the menstrual cycle and disorders in it (dysmenorrhea, polymenorrhea, oligomenorrhea) or its absence (amenorrhea), if any. The patient is asked about the presence of diagnosed diseases of the genital tract, such as uterine fibroids, polyps, endometriosis, pelvic inflammatory disease, sexually transmitted infections, and about undergone gynecological operations. Obstetric anamnesis is taken – number of births, abortions, pregnancy complications, mode of delivery. The anamnesis of the couple’s sexual life is of no small importance – the frequency of sexual contacts is important, since both very frequent (1-2 and more times a day) and less frequent (several times a month) sexual contacts can be the cause for infertility. Family history is also of great importance, which is why infertility in the family, genetic diseases, etc. are inquired about. After taking an anamnesis, a physical examination is performed, during which her weight and body mass index are determined, palpation of the thyroid gland, breast palpation to determine galactorrhea, and a gynecological examination are performed. During a gynecological examination, the external genitalia, vagina and cervix are examined, material is taken for smear and microbiology, and bimanual palpation is performed. During palpation, a change in the position, mobility and size of the uterus can be detected, pain, tension, tumor masses can be diagnosed. An ultrasound examination of the small pelvis is performed, which has considerable diagnostic value.The diagnosis of infertility in women goes through certain stages and sets of research: 1. Diagnostic tests to assess ovarian function – to determine the presence or absence of ovulation, it is recommended to measure the basal temperature (BT). It is measured every morning before getting up, and during ovulation, an increase in the normal temperature by 0.4-0.8 degrees is observed. To determine the presence of ovulation, folliculometry is also performed – in a woman with a menstrual cycle of 28 days, a test is performed on days 10, 12 and 14, when a growing follicle can be detected. Hormonal studies have a major role in evaluating ovarian function. On the 3rd-4th day of menstruation, follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, prolactin are tested, and on the 21st day of the monthly cycle – progesterone. Another important hormone is Anti-Müllerian hormone (AMH). 2. Diagnostic tests to assess the function of the fallopian tubes – to assess the patency of the fallopian tubes, hysterosalpingography (HSG), the so-called color photo of fallopian tubes. A greater diagnostic value, but also a more invasive method, is laparoscopy, in which the organs in the small pelvis are inspected under full anesthesia. With the help of these methods, the fallopian tubes are checked for adhesions and, if present, are removed during laparoscopy; 3. Diagnostic tests to assess the condition of the uterine cavity – the gold standard in this area is hysteroscopy, in which the uterine cavity is examined again with the help of a camera. Another diagnostic method is sonohysterography – the penetration of a contrast substance into the uterine cavity is tracked using ultrasound. 4. Examination of thyroid hormones – triiodothyronine (fT3), thyroxine (fT4) and thyroid-stimulating hormone (TSH) are tested to determine hypofunction or hyperfunction, and TAT, MAT and TSH antibodies are also tested to diagnose an autoimmune disease -receptor antibodies. Sources: Gynecology edited by Prof. Dr. Angel Dimitrov, MD, PhD. and Prof. Dr. Viktor Zlatkov, MD, 2017 https://www.ncbi.nlm.nih.gov/books/NBK556033/Diagnostic tests to assess the function of the fallopian tubes – to assess the patency of the fallopian tubes, hysterosalpingography (HSG), the so-called color photo of fallopian tubes. A greater diagnostic value, but also a more invasive method, is laparoscopy, in which the organs in the small pelvis are inspected under full anesthesia. With the help of these methods, the fallopian tubes are checked for adhesions and, if present, are removed during laparoscopy; 3. Diagnostic tests to assess the condition of the uterine cavity – the gold standard in this area is hysteroscopy, in which the uterine cavity is examined again with the help of a camera. Another diagnostic method is sonohysterography – the penetration of a contrast substance into the uterine cavity is tracked using ultrasound. 4. Examination of thyroid hormones – triiodothyronine (fT3), thyroxine (fT4) and thyroid-stimulating hormone (TSH) are tested to determine hypofunction or hyperfunction, and TAT, MAT and TSH antibodies are also tested to diagnose an autoimmune disease -receptor antibodies. Sources: Gynecology edited by Prof. Dr. Angel Dimitrov, MD, PhD. and Prof. Dr. Viktor Zlatkov, MD, 2017 https://www.ncbi.nlm.nih.gov/books/NBK556033/Diagnostic tests to assess the function of the fallopian tubes – to assess the patency of the fallopian tubes, hysterosalpingography (HSG), the so-called color photo of fallopian tubes. A greater diagnostic value, but also a more invasive method, is laparoscopy, in which the organs in the small pelvis are inspected under full anesthesia. With the help of these methods, the fallopian tubes are checked for adhesions and, if present, are removed during laparoscopy; 3. Diagnostic tests to assess the condition of the uterine cavity – the gold standard in this area is hysteroscopy, in which the uterine cavity is examined again with the help of a camera. Another diagnostic method is sonohysterography – the penetration of a contrast substance into the uterine cavity is tracked using ultrasound. 4. Examination of thyroid hormones – triiodothyronine (fT3), thyroxine (fT4) and thyroid-stimulating hormone (TSH) are tested to determine hypofunction or hyperfunction, and TAT, MAT and TSH antibodies are also tested to diagnose an autoimmune disease -receptor antibodies. Sources: Gynecology edited by Prof. Dr. Angel Dimitrov, MD, PhD. and Prof. Dr. Viktor Zlatkov, MD, 2017 https://www.ncbi.nlm.nih.gov/books/NBK556033/