May Cigarettes Smoking Trigger Early Menopause?

Cigarette smoking is bad for the health. But for women, it may cause additional negative side effects, associated with triggering the earlier onset of menopause. Multiple studies have confirmed that tobacco smoking can actually affect the timing of the onset of menopause, the intensity of the symptoms of menopause, and the incidence of osteoporosis after menopause.

Women who smoke need to recognize these risks and do their best to kick the habit.

Massachusetts General Hospital Study

Menopause occurs when the ovaries cease to produce estrogen. A gene, Bax, and a genetic receptor, Ahr, are responsible for the onset of menopause when they become activated. Researchers at Massachusetts General Hospital have discovered that the chemicals in smoking directly activate these genetic components, creating what they call a “specific pathway” to killing ovarian cells.

It has been found that women who smoke more than ten cigarettes a day are 40 percent more likely to go into menopause early than nonsmokers. As was generally observed by the result of the study, women who smoke will enter menopause one to two years earlier.

University of Oslo, Norway, Study

Some interesting results were received by Norwegian scientists, who tried to review multiple factors as potential triggers for the menopause to strike earlier than expected statistically. Here are the important findings of the study:

• The study showed substantial association between current smoking and early onset of menopause, and that the earlier a woman stops smoking, the more protection she derives with respect to an early onset of menopause.
• While female smokers increase their risks to escalate the menopause onset, the study did not find any relationship between passive exposure to smoking and early menopause.
• No association was revealed between early menopause and alcohol or coffee consumption.

University of Hong Kong Study

The most recent study, which was carried in the journal Menopause, pooled data from several previous studies that included about 6,000 women in the United States, Poland, Turkey and Iran.

The researchers concluded that while non-smokers hit menopause between age 46 and 51, on average, in all but two of the reviewed previous studies, smokers were younger when they hit menopause, between 43 and 50 overall.

"Our results give further evidence that smoking is significantly associated with earlier (age at menopause) and provide yet another justification for women to avoid this habit," wrote study author Volodymyr Dvornyk, from the University of Hong Kong.

Dvornyk and his colleagues also analyzed five other studies that used a cut-off age of 50 or 51 to group women into "early" and "late" menopause. Out of more than 43,000 women in that analysis, women who smoked were 43 percent more likely than nonsmokers to have early menopause.

Both early and late menopause factors have been linked to health risks. Women who hit menopause late, for instance, are thought to be at higher risk of breast cancer because one risk factor for the disease is more time exposed to estrogen.

"General consensus is that earlier menopause is likely to be associated with the larger number and higher risk of postmenopausal health problems, such as osteoporosis, cardiovascular diseases, diabetes mellitus, obesity, Alzheimer's disease, and others," explained Dvornyk. Overall, he added, early menopause is also thought to slightly raise a woman's risk of death in the years following.

There are two theories for why smoking might mean earlier menopause, said Jennie Kline, an epidemiologist from Columbia University's Mailman School of Public Health in New York. Smoking make have an effect on how women's bodies make, or get rid of, estrogen. Alternatively, some researchers believe certain components of cigarette smoke might kill eggs, added Kline, who was not involved in the study.

Dvornyk's team did not have information on how long women had been smoking or how many cigarettes they smoked each day, so his team could not determine how either of those factors may have affected age at menopause. For that reason, and a lack of data on other health and lifestyle factors linked to menopause, the analysis may not be enough to resolve lingering questions on the link between smoking and menopause, they said.

Alcohol, weight and whether or not women have given birth may each also play a role in when they hit menopause, but the evidence for everything other than smoking has been mixed, Kline said. It is also possible that the same factors that influence age at menopause may determine whether women have trouble with infertility or not, or how late they can get pregnant.

Conclusion

While there is a definite connection between smoking and menopause, but can smoking indeed cause early menopause? "Smoking can cause a woman to go through menopause a year or two earlier, but it isn't going to push a woman into menopause before the age of 40," says Geoffrey Redmond, MD, director of the Hormone Center of New York. So, in other words, smoking may cause the earlier menopause, but is unlikely to cause the early menopause in strict scientific terms.

Sources and Additional Information:

http://www.lbfmd.com/whs_menopause_211_8051.pdf

http://www.biomedcentral.com/1471-2458/7/149

http://www.reuters.com/article/2011/10/17/us-menopause-smoking-idUSTRE79G08Q20111017

http://www.everydayhealth.com/menopause/early-menopause.aspx

http://www.catherinepickenmd.net/early-menopause-linked-to-smoking.html

Main Causes of Early (or Premature) Menopause

Early menopause and premature menopause are terms that are often used interchangeably. Both terms may cover a wide range of the different medical situations and conditions, like premature ovarian failure, surgical menopause, or menopause caused by chemotherapy or radiation.

The link between all these conditions is woman’s age, when the menopause symptoms are observed. As stated, early or premature menopause is typically used to mean menopause that comes well before the average age of normal menopause when you're still in your 20s, 30s, or early 40s. 

More technically, as used by many doctors and medical journals:  

• Early menopause refers to menopause before the age of 45. 
• Premature menopause is menopause that occurs before age 40.  

Medical treatments that may cause early menopause include:

• Chemotherapy or pelvic radiation treatments for cancer. These treatments can damage the ovaries and cause your periods to stop. Effects like having trouble getting pregnant can happen right away or several months later. The chances of going into menopause depend on the type and amount of chemotherapy that was used. Also, the younger a woman is, the lower the chances that she will experience menopause.
• Surgery to remove the ovaries. Surgical removal of both ovaries, also called a bilateral oophorectomy (OH-uh-fuh-REK-tuh-mee), causes menopause right away. A woman’s periods will stop after this surgery, and her hormones drop quickly. She may immediately have strong menopausal symptoms, like hot flashes and diminished sexual desire.
• Surgery to remove the uterus. Some women who have a hysterectomy (his-tur-EK-tuh-mee), which removes the uterus, are able to keep their ovaries. They will not enter menopause right away because their ovaries will continue to make hormones. But, because their uterus is removed, they no longer have their periods and cannot get pregnant. They might have hot flashes because the surgery can sometimes affect the blood supply to the ovaries. Later on, they might have natural menopause a year or two earlier than expected.

• Surgery to remove fallopian tubes.  Fallopian tubes removal causes early menopause. Hormone and egg production is dramatically interrupted, leading to the onset of early or premature menopause.
• Tubal Ligation. Often women that have undergone a tubal ligation procedure enter menopause at an earlier age.
• Tamoxifen. Tamoxifen used to be prescribed after you were diagnosed for breast cancer -- and, as with other forms of chemo, you would run a risk for premature menopause as a side effect. But recently doctors have begun prescribing Tamoxifen as a preventative to women with a high risk for breast cancer, since it cuts breast cancer rates by about 45 percent.  While the media has focused on the positive aspects of this drug (and there are many), there is an important potential side effect to Tamoxifen that hasn't been played up a great deal: it can send you into premature menopause. 

Sometimes, menopause occurs early on its own. Some possible causes include:

• Chromosome defects. Problems in the chromosomes can cause premature menopause. For example, women with Turner's syndrome are born without all or part of one X chromosome. The ovaries don't form normally, and early menopause results.
• Genetics. Women with a family history of early menopause are more likely to have early menopause themselves.
• Autoimmune diseases. The body's immune system, which normally fights off diseases, may mistakenly attack the ovaries and prevent them from making hormones. Thyroid disease and rheumatoid arthritis are two diseases that can cause this to happen.
• Infection. Infection is also linked with premature menopause. Infections such as the mumps and tuberculosis can infect the ovaries, affecting your hormonal balance. This is extremely rare, however.
• Stress. Although stress cannot cause early menopause by itself, it does play an important role in the severity and frequency of symptoms.

When menopause comes early on its own, it sometimes has been called “premature menopause” or “premature ovarian failure.” But a better term is “primary ovarian insufficiency,” which describes the decreased activity in the ovaries. In some cases, women have ovaries that still make hormones from time to time, and their menstrual periods return. Some women can even become pregnant after the diagnosis.

This is yet another instance where you're often still getting fairly regular periods -- and your hormone levels aren't testing at post-menopausal levels, but you're getting symptoms. When this occurs before the age of 40, it's often viewed as a precursor to premature ovarian failure and is referred to as diminished ovarian reserve. 

Sources and Additional Information:

http://www.earlymenopause.com/whatis.htm

http://www.epigee.org/menopause/early.html

http://www.34-menopause-symptoms.com/early-menopause.htm