A hysterectomy is a surgical procedure involving the removal of the uterus. While this surgery provides relief for many conditions, patients often worry about resulting changes in hormone levels. The uterus itself is not an endocrine organ and does not produce sex hormones. The answer to whether hormones will still be present depends entirely on whether the ovaries are removed along with the uterus, as the ovaries are the primary source of these hormones.
Understanding the Surgical Variations
The impact of a hysterectomy on hormonal balance is dictated by the extent of the surgery. The procedure may involve removing only the uterus, which leaves the ovaries and their hormone-producing function intact; this is known as a hysterectomy with ovarian conservation. The other main scenario involves the removal of both the uterus and the ovaries.
The ovaries are the glands responsible for generating the majority of the body’s estrogen, progesterone, and a portion of testosterone. When the ovaries are left in place, the core endocrine function remains. Conversely, removing the ovaries eliminates the primary source of these hormones, immediately triggering a profound hormonal shift.
Hormone Production When Ovaries Remain
When the ovaries are preserved during a hysterectomy, they continue their endocrine function, producing sex hormones as they did before the operation. This means the body’s levels of estrogen and testosterone remain largely the same, and the individual will not experience the sudden onset of hormonal deficiency symptoms. While the ovaries still produce progesterone, its cyclical effects are no longer apparent because the menstrual cycle, which requires the uterus, has ended.
Some individuals with retained ovaries may experience the onset of natural menopause slightly earlier than the average age of 51. This is thought to occur because the blood supply to the ovaries can be partially compromised when the uterine arteries are tied off during the hysterectomy. The resulting subtle reduction in blood flow can gradually impair ovarian function over time, mirroring the process of natural menopause.
Hormonal Changes Following Ovarian Removal
The most dramatic hormonal changes occur when both ovaries are removed, a procedure called a bilateral oophorectomy. Because the ovaries are the primary endocrine organs for sex hormones, their simultaneous removal causes an immediate and sharp drop in the levels of estrogen, progesterone, and testosterone. This abrupt hormonal withdrawal is known as surgical menopause, which is distinct from natural menopause.
Natural menopause typically unfolds over several years, allowing the body to adapt to the gradual decline in hormone production. Surgical menopause, in contrast, forces the body into an immediate state of hormone deficiency. The sudden lack of estrogen commonly results in severe menopausal symptoms, such as intense hot flashes, night sweats, and vaginal dryness.
This sudden hormonal loss can also have significant long-term health implications, including an accelerated loss of bone density, increasing the risk of osteoporosis. The protective effects of estrogen on cardiovascular health are also lost, which can increase the lifetime risk of heart disease.
Hormone Sources Beyond the Ovaries
Even after the removal of both ovaries, the body does not cease all sex hormone production. The adrenal glands, situated atop the kidneys, produce precursor hormones, such as dehydroepiandrosterone (DHEA) and androstenedione. These precursor hormones are a source of weak androgens.
Peripheral fat tissue, known as adipose tissue, also plays a role in hormone production through an enzymatic process called aromatization. This process converts some of the androgens produced by the adrenal glands into a weak form of estrogen called estrone. While these peripheral sources provide a background level of hormones, they are generally not sufficient to prevent the symptoms or health risks associated with the major hormonal loss.