a) Ovary

The ovaries are the paired female gonads. They are responsible for the development of the female's gametes as well as for production of the sex hormones (oestrogen and progesterone). Unlike the male gonads, the ovaries do not continually generate new gametes throughout life. Once the supply of oocytes is exhausted, ovarian function ceases and menopause ensues.


The ovaries are suspended in the peritoneal cavity by a folded sheet of peritoneum - the mesovarium. They are found in the most lateral and posterior part of the broad ligament, separated from the retroperitoneal structures by the ovarian fossa, part of the peritoneal cavity. The mesovarium attaches to the pelvic sidewall between the internal and external iliac vessels but the exact position of the ovary is variable.
The ovaries are typically pearlescent white in young women; as ovarian follices rupture during life they become scarred and dull in appearance.
The size of the ovaries varies considerably with age and hormonal status. In non-pregnant adults, the ovaries are about 4 cm in length and 3 cm in breadth. Before puberty they are about one third of this size, and they also shrink after menopause is reached. During pregnancy they can double in size.

Microscopic Structure

The ovary contains three parts:

  • The capsule consists of the germinal epithelium, formed by simple cuboidal epithelium. Beneath this epithelium is the tunica albugenia, formed by dense connective tissue. Oocytes penetrate this capsule when follicle rupture occurs.
  • The cortex contains the follicles in various stages of development and the supporting stroma
  • The medulla contains the nutrient vessels and loose connective tissue

The cortex is the most complicated tissue in the ovary. It consists of follicles and stroma

  • Follicles are described according to their stage of development
    • Primordial Follicles are present at birth, and lie in the superficial part of the cortex. They are large cells with a surrounding layer of flattened folliclular cells.
    • Primary Follicles are the first stage in development. Oocytes secrete the zona pellucida which separates them from the follicular cells. The follicular layer differentiates into granulosa cells which line the zona pellucida. Stromal cells of the ovary differentiate into concentric layers around the granulosa cells, forming theca cells.
    • Secondary Follicles develop from some of the primary follicles during the menstrual cycle. The granulosa layer becomes stratified and secretes fluid into a separate space known as the antrum. The oocyte and surrounding granulosa cells bulge into the antrum as the cumulus oophorus. The theca cell layers continue to enlarge and begins to secrete steroids; the granulosa cells convert this to oestrogens.
    • Tertiary Follicles are usually single, the remaining primary and secondary follicles undergoing atresia. The oocyte and its surrounding granulosa cells separate from the internal wall of the follicle (the granulosa cells are referred to as the corona radiata) and float within the antrum. The follicle erodes the overlying capsule and ejects the antral fluid and oocyte with surrounding


  • Lateral - The pelvic side wall
  • Medial - The broad ligament and uterus
  • Posterior - The internal iliac vessels, obturator nerve
  • Anterior - The external iliac vessels
  • Inferior - Pelvic floor

Appearance on Imaging


Neurovascular Supply

Arterial Supply

Venous Drainage



Potential Routes of Malignant Spread