Male Infertility Workup

A 32-year-old man presents to the fertility clinic with his wife for evaluation of primary infertility of 3 years' duration. The wife's investigations are normal. On examination, the patient has small, firm testes bilaterally (volume ~8 mL each). General examination reveals gynecomastia. Semen analysis shows azoospermia with low ejaculate volume (1.2 mL). Serum FSH is 28 IU/L (normal 1.5–12), LH is 32 IU/L (normal 1.7–8.6), and testosterone is 2.1 ng/mL (normal 2.5–8). What is the most likely diagnosis?

A 38-year-old man attends the fertility clinic with his wife for evaluation of secondary infertility (2 years' duration; one child born 8 years ago). He reports a history of mumps orchitis at age 19. On examination, the left testis is atrophic (volume ~4 mL), firm, and tender to palpation; the right testis is normal (15 mL). Semen analysis shows oligozoospermia with 8 million/mL sperm concentration and 20% motility. Serum FSH is 12 IU/L (normal 1.5–12), LH is 7.2 IU/L (normal 1.7–8.6), and testosterone is 5.8 ng/mL (normal 2.5–8). What is the most appropriate next investigation?

Which hormone level should be measured FIRST in the initial hormonal evaluation of a man presenting with azoospermia?

In the evaluation of male infertility, what is the PRIMARY abnormality detected in a semen analysis showing oligozoospermia with normal motility and morphology?

A 38-year-old man attends the fertility clinic with his wife for evaluation of primary infertility (3 years of unprotected intercourse). He has a history of bilateral cryptorchidism treated surgically at age 6 years. On examination, both testes are small (approximately 8 mL each) and soft. Semen analysis shows azoospermia (no sperm in ejaculate), normal volume (3 mL), and normal pH (7.2). Serum FSH is markedly elevated at 28 IU/L (normal <12), LH is 18 IU/L (normal <8), and testosterone is 2.8 ng/mL (normal 2.5–8). Post-ejaculatory urinalysis is negative for sperm. What is the most likely diagnosis?