The ovaries are the paired reproductive glands in the female body, responsible for producing eggs and secreting hormones. While their function is well-known, their precise location within the body often leads to questions about how low they are situated. These small, almond-shaped organs are found deep within the bony structure of the pelvis, generally positioned in the lower abdominal area. Understanding their anatomical placement, physical size, and natural mobility helps to clarify their usual resting spot and the factors that can cause their position to shift.
Anatomical Placement Within the Pelvis
The ovaries are located on either side of the uterus, nestled against the lateral walls of the true pelvis. Their typical resting spot is a shallow depression on the pelvic wall known as the ovarian fossa. This fossa is bounded by important structures like the external iliac vessels and the ureter, placing the ovaries quite low and posterolateral to the uterus.
This position is maintained by a set of supporting structures, which function like a suspension system. The ovarian ligament connects the ovary to the side of the uterus, acting as an anchor. Meanwhile, the suspensory ligament extends from the ovary to the lateral pelvic wall, carrying the major blood vessels and nerves. The broad ligament of the uterus also contributes to the support system by enclosing the ovary via a fold of tissue called the mesovarium.
Physical Characteristics and Size
The ovaries are typically oval or almond-shaped in adult women. Their average size is about 3 to 5 centimeters (cm) in length, 2 cm in width, and 1 cm in thickness. They are roughly the size of a large grape or a small walnut.
The dimensions of the ovaries are not constant, as they undergo monthly fluctuations related to the reproductive cycle. For instance, the development of a dominant follicle leading up to ovulation can temporarily increase the size of one ovary. After menopause, the ovaries naturally decrease in size, often shrinking to less than 2 cm in length due to the cessation of follicle development and hormone production.
Understanding Ovarian Mobility and Variation
The ovaries are not rigidly fixed within the pelvic cavity, which allows their position to vary slightly. The ligamentous supports, particularly the suspensory ligament, provide enough slack for a degree of movement within the pelvis. This natural mobility is a consequence of their suspension system.
Daily activities and the fullness of nearby organs, such as the bladder and bowel, can cause the ovaries to shift slightly in the anteroposterior and craniocaudal directions. More significant changes occur with pregnancy, as the enlarging uterus pulls the supporting ligaments, often displacing the ovaries upward. Pathological conditions like endometriosis can also affect mobility, where scar tissue can tether or fix an ovary to the pelvic wall or surrounding structures, preventing its normal movement. The left ovary may also have slightly less range of motion compared to the right, possibly due to the proximity of the sigmoid colon.