The infertility rate in society is approximately 15%. Male factor is responsible for approximately half of infertile couples. Causes of male infertility: Varicocele, Obstruction, Testicles remaining in the inguinal canal, Immunological causes, Ejaculatory disorders, Testicular failure, Gonadotoxins, Endocrinological factors, Infection, Sexual dysfunction, Systemic diseases, Sertoli Cell Only syndrome, Genetic factors. The following methods are followed in the evaluation of infertile men: - Detailed anamnesis: Here, the duration of infertility, previous examinations and treatments, frequency of intercourse, infections experienced in childhood, Systemic diseases (such as Diabetes, Multiple Sclerosis), Previous surgical operations, medications used, family history are taken. - Physical examination: A small penis size may be a warning for hypogonadism. Sensitivity or hardness in the urethra can be the cause of urethritis or urethral stricture. It may be. Evaluation of the volume of the testicles is very important. Low testicular volume is parallel to low sperm production. The long axis of the testicles is at least 4 cm. The consistency of the testicles is also very important, they should not be too hard - nodular or too soft. Hard epididymis may indicate chronic epididymitis and obstruction. If varicocele is palpable, it may cause testicular atrophy and deterioration in semen parameters. If vascular dilatations are palpable during examination, varicocele, which may be 2nd or 3rd degree, may benefit from surgery. - Laboratory tests: First, semen analysis should be started. 3 days of sexual abstinence is required for semen analysis. WHO reference values: Sperm morphology determines the fertilization ability of the sperm. There is a direct correlation between normal morphology, i.e. shape, and good sperm function. Causes of morphological disorders include congenital anomalies, varicocele, high fever, infections, smoking, alcohol, drugs. The ideal period for morphological disorders is 6 weeks. Then repeat the semen analysis and see if the problem persists. Hormonal evaluation: If the examination is normal or there is obstruction, FSH, LH, Testosterone are normal. If there is spermatogenic insufficiency, FSH is high. LH and Testosterone are normal. If there is testicular insufficiency, FSH, LH are high and Testosterone is normal or low. In hypogonadism, all hormones are low. FSH hormone reflects the functional status of seminiferous tubules. If it is 2-3 times higher, it reflects that spermatogenesis is negatively affected. LH hormone induces the release of testicular testosterone from Leydig cells. Karyotype anomalies, which are 6% in infertile men, are found in 10-15% in azoospermics. Monosomy, trisomy, translocations are also detected as anomalies. Sex chromosome anomalies are more common in azoospermic patients, and autosomal chromosome anomalies are more common in oligospermics. Spermatogenesis is caused by Y It is known that the chromosome is responsible. Microdeletions that will occur in the genes in the AZF region on the Y chromosome negatively affect spermatogenesis. Surgical sperm retrieval methods: MESA: It is a technique of obtaining sperm from the epididymis through open microsurgical intervention. It is applied in cases where it is not possible to correct obstructive cases. PESA: It is performed with local anesthesia, it is a minimally invasive surgical procedure. It is performed in cases of obstruction. But it is not performed by most centers. TESA: It is performed in cases where the epididymis is not suitable for methods such as MESA or PESA and sperm production is known. TESE: It is an open surgical method. It is performed by taking tissues with a high probability of obtaining sperm into a petri dish and examining them. It is performed especially in cases with non-obstructive azoospermia to obtain sperm. Since testosterone in the testicles will be suppressed after the TESE procedure, a recovery period of up to 6 months should be given. MICROTESE: The procedure of taking samples from the testicles is performed under an operating microscope, magnified 20-30 times. is performed. Here, dilated tubules are collected and tissues with a high probability of sperm extraction are taken. It is performed under general anesthesia and takes 1.5-2 hours. The sperm detection rate is approximately 50%. Even in Klinefelter cases, the sperm detection rate with MICROTESE is approximately 30-40%. Klinefelter syndrome is an indication for PGT.