Ladies, Keep Your Ovaries!
By Jannet Huang, MD, FRCPC, FACE, ABHM, Menopause Clinician and board certified in Endocrinology & Metabolism
A question that I often get is “I need a hysterectomy. Should I keep my ovaries? My surgeon wants to take them out. He says they are not doing anything anyway since I am menopausal. What should I do?”
A study published in the May issue of Obstetrics and Gynecology will hopefully change the way gynecologists approach oophorectomy (surgical removal of the ovary) differently. The breaking news:
Bilateral oophorectomy (removal of both ovaries) at the time of hysterectomy for benign disease is associated with reduced risk of breast and ovarian cancers, but an INCREASED risk of all-cause mortality, coronary heart disease and lung cancer.
Bilateral oophorectomy at the time of hysterectomy for benign disease is often practiced by gynecologists in the US to prevent the subsequent development of ovarian cancer. (Note that ovaries need to be removed during surgery for gynecological cancers. This article is referring to hysterectomy for benign conditions such as fibroids, dysfunctional uterine bleeding or prolapse, etc.) Oophorectomy before menopause leads to an abrupt decrease in estrogen and androgen (male hormone) levels. Removal of the ovaries after menopause also impacts a woman’s hormonal balance. The statement that is often told to patients – “you are in menopause, your ovaries are not doing anything anyway” is certainly NOT true. After menopause, our ovaries are still responsible for producing 50% of our androgens. Furthermore, new hormones and factors are identified every day, so there is probably a wealth of other hormones that our ovaries make after menopause which we have not identified yet.
The goal of this study was to compare long-term health outcomes after oophorectomy or ovarian conservation (ie. Letting the women keep their ovaries) in 29,380 women participants of the Nurses' Health Study who had a hysterectomy for benign disease. Of these, 16,345 (55.6%) had hysterectomy with bilateral oophorectomy, and 13,035 (44.4%) had hysterectomy with ovarian conservation. Duration of follow-up was 24 years.
Bilateral oophorectomy was associated with an increased risk of coronary heart disease; this increase was statistically significant for all women with multivariable hazard ratio (HR ) of 1.17, especially for women having oophorectomy before age 45 years (HR 1.26). Breast cancer was less frequent among all women having oophorectomy (HR 0.75), and the risk was lower among women having oophorectomy before the age of 45 years (HR 0.62). Oophorectomy was associated with a markedly reduced risk of ovarian cancer (HR 0.04), an increased risk of lung cancer (HR 1.26), and a reduction in total cancers (HR 0.90). Risks of stroke, hip fracture, colorectal cancer, and pulmonary embolism did not differ significantly between groups.
Compared with women who kept their ovaries, women who had bilateral oophorectomy had HR of 1.12 for all-cause mortality. (Translation: a 12% increase in risk of dying from any cause. For every 24 women having bilateral oophorectomy, at least one woman will die prematurely from any cause as a result of the oophorectomy.) Analysis of cause-specific mortality found an increased risk of death from CHD (HR 1.28), lung cancer (HR 1.31), and all cancers (HR 1.17), a reduced risk of death from ovarian cancer (HR 0.06), and no overall difference in deaths from stroke, breast cancer, or colorectal cancer. (*please note that all cited HRs are statistically significant with 95% confidence intervals.)
The investigators also performed an analysis of the 10,094 women who had either bilateral oophorectomy or ovarian conservation and had never used estrogen therapy (ET). Those who never used ET who had oophorectomy before age 50 years had almost double the risk of incident coronary heart disease (HR 1.98). Oophorectomy was associated with a significantly increased risk of stroke for all women (HR 1.85) and especially for women aged younger than 50 years at the time of surgery (HR 2.19). Oophorectomy was even associated with an increased risk of lung cancer (HR 2.09). The risk of all-cause death was significantly higher among women aged younger than 50 years at the time of surgery (HR 1.40 – translation – there is 1 excess death for every 9 surgeries performed with bilateral oophorectomy). The risks of breast cancer, colorectal cancer, total cancer, hip fracture, and pulmonary embolus were no different among women who had never used ET. In my opinion, these findings support the protective effect of estrogen therapy.
The above findings provide evidence that, for women not at high risk for ovarian cancer, oophorectomy may actually adversely affect long-term health outcomes and mortality, and at no age was oophorectomy associated with a survival benefit. Preventive surgery should not be performed if it does not clearly benefit the patient.
Surgeons recommending oophorectomy at the time of hysterectomy are certainly well-meaning, thinking that they are helping their patients reduce the risk of ovarian cancer. This common practice will hopefully change with the above study finding excess morbidity and mortality in women who had oophorectomy, especially those who did not take estrogen therapy. It is estimated that 300,000 US women undergo elective oophorectomy at the time of hysterectomy each year, so this study will have a large impact on women’s health.
On another note, 2 studies conducted at the Mayo Clinic published in August 2007 (data for the 2 studies was derived from the Rochester Epidemiology Project, one of the largest long-term integrated databases of patient records in the world) showed that women who underwent oophorectomy before menopause had almost double the risk of developing dementia or parkinsonism. The younger the women at the time of surgery, the greater the risk. Another surprising but distressing finding of these studies is that even removal of one ovary seems to have the same adverse effect neurologically as removal of both ovaries. However, a reassuring finding in this study is that women who had their ovaries removed but received estrogen replacement therapy returned to normal risk. I think this is yet another piece of evidence supporting the benefit of estrogen therapy started at the time of surgical menopause.
I would advise women to have a thorough discussion with their gynecologists about the risk of cardiovascular disease, neurological conditions and cancers, as well as aspects affected by reduction in androgen levels (such as overall well-being and sexuality) prior to making their decisions about whether to have their ovaries conserved or removed at the time of hysterectomy.
~By Jannet Huang, MD, FRCPC, FACE, ABHM, Menopause Clinician and board certified in Endocrinology & Metabolism