Petefészek

Petefészek, or ovary, is one of the paired female reproductive organs. In humans it sits in the pelvis on each side of the uterus, near the lateral pelvic wall, connected to the uterus by the ovarian ligament and to the pelvic cavity by the mesovarium. The fimbriae of the fallopian tube are adjacent to the ovary and help capture the oocyte at ovulation. Each ovary is almond-shaped and varies in size with age and hormonal status. Blood supply comes from the ovarian arteries, branches of the abdominal aorta; venous drainage is via the ovarian veins to the renal vein on the left and the inferior vena cava on the right.

Internal structure and function: The ovary consists of an outer cortex and an inner medulla. The cortex hosts follicles at various developmental stages, containing oocytes surrounded by supporting cells. The medulla contains blood vessels and connective tissue. During the menstrual cycle, a cohort of follicles begins to mature, usually one becomes dominant and releases an oocyte during mid-cycle (ovulation). After ovulation, the ruptured follicle forms the corpus luteum, which secretes progesterone and estrogen. The ovary also produces small amounts of androgens and contributes to systemic hormonal balance.

Development and regulation: Ovaries originate from the gonadal ridges of the intermediate mesoderm. Primordial germ cells migrate there and form oogonia that become primary oocytes before birth. At puberty, the hypothalamic-pituitary-ovarian axis increases FSH and LH, triggering follicular development, ovulation, and the luteal phase. Hormones such as estrogen and progesterone coordinate the ovarian and uterine cycles.

Clinical notes: Common conditions include functional ovarian cysts, polycystic ovary syndrome (PCOS), endometriomas, and ovarian cancer risk increases with age. Ovarian function declines with menopause, impacting fertility and hormone production.