Male infertility affects millions of couples worldwide, arising from various factors that impact different stages of the reproductive process. An endocrine imbalance resulting from conditions like hypogonadism, Klinefelter syndrome, or pituitary disorders can disrupt hormone levels and reduce sperm production. Testicular defects, such as tumors, cryptorchidism, atrophic testes, abnormal sperm morphology, and low sperm count or motility, may arise due to genetic factors, structural...

A tough, fibrous membrane, the tunica albuginea, covers the testes, extending inward to form fibrous partitions or septa, dividing them into internal compartments called lobules. Each lobule has 1 to 3 tightly coiled seminiferous tubules where sperm production occurs. These tubules merge into a tubular network at the back of the testis, known as the rete testis. It connects to 15 to 20 efferent ductules, leading to the epididymis.
The spermatogenic cells, responsible for producing sperm, are...

The testes, also known as testicles, are the male gonads. They are housed within the scrotum, a sac-like structure located beneath the penis. The scrotum's primary role is to regulate the temperature of the testes, which is crucial for sperm production.
Each testis is surrounded by the tunica albuginea, a dense connective tissue layer that provides structural support and protection. This layer is covered by an outer serous membrane called the tunica vaginalis, which helps reduce friction...

Female infertility is defined as the inability to conceive after a year of regular, unprotected intercourse and affects about 10–15% of couples worldwide. The primary cause of female infertility is ovulatory disorders, which hinder the release of eggs. These disorders can be classified as hypothalamic amenorrhea, polycystic ovarian syndrome (PCOS), premature ovarian failure, and hyperprolactinemic anovulation disorders.
Endometriosis, a condition characterized by abnormal growth of endometrial...

In vitro fertilization (IVF) is a form of assisted reproductive technology where an egg is fertilized with sperm in a controlled laboratory environment before transferring the resulting embryo into the uterus. This process is designed to help individuals and couples experiencing difficulties conceiving.
The IVF process begins with ovarian stimulation, during which reproductive endocrinologists prescribe hormonal medications to stimulate the ovaries to produce multiple eggs instead of the single...

Spermatogenesis is the process by which haploid sperm cells are produced in the male testes. It starts with stem cells located close to the outer rim of seminiferous tubules. These spermatogonial stem cells divide asymmetrically to give rise to additional stem cells (meaning that these structures “self-renew”), as well as sperm progenitors, called spermatocytes. Importantly, this method of asymmetric mitotic division maintains a population of spermatogonial stem cells in the male reproductive...