5 things that could disrupt your period

For many women, their menstrual cycles run like clockwork. But even the most consistent of periods can be sent out of whack by your habits and lifestyle. Here are 5 common – but surprising – period disrupters

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Plane travel

Long distance air travel can send your menstrual cycle off course. “Travelling through time zones can disrupt your body’s circadian rhythm,” says Dr. Prati Sharma, a reproductive endocrinologist at the Create Fertility Centre, and an associate physician at Sunnybrook and Women’s College Hospitals in Toronto. Your circadian rhythm is responsible for your sleep-wake cycles, and the release of hormones. It typically follows a 24-hour cycle and responds to light and darkness in your environment. Flying across time zones can upset the circadian rhythm and by proxy your menstrual rhythm. “This disruption is due to an alteration in two hormones – cortisol (the stress hormone) and melatonin (a hormone that’s affected by exposure to light),” says Dr. Sharma. “There’s lots of data that suggests that flight attendants have menstrual irregularity – longer or shorter cycles.”

Most women who take a single 6-hour flight won’t notice any differences, but women who fly frequently between Europe and North America could be affected.

Women who have chronic insomnia or jobs that include overnight shifts could also experience menstruation disturbances as a result of a lack of light exposure and changes in their circadian rhythm.

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Extreme stress

Acute stress following job loss, a death of a loved one, a divorce or even a long-term illness can derail your cycle. When your body is under extreme stress, cortisol – your body’s stress hormone – increases. While it helps your body deal with the influx of stressful symptoms, cortisol can also interfere with your menstrual cycle. “Stress is associated with lower estrogen levels during your cycle, lower luteinizing hormone levels (responsible for ovulation; if your LH hormones are low you’re not going to ovulate regularly), and higher follicle stimulating hormones (responsible for proper egg development),” says Dr. Sharma. High stress is also associated with lower levels of the hormone progesterone during the second half of your cycle, and can cause you to have either really long periods or extremely short ones. “You might not ovulate regularly and your cycles are going to be irregular whether that’s longer or shorter,” she says.

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Excessive alcohol consumption

According to the Canadian alcohol consumption guidelines, adult women can safely consume up to 10 alcoholic drinks per week. But studies have shown that drinking more than that amount can seriously impact your reproductive hormones and interfere with menstrual flow. A 2012 Japanese study compared two groups of women over three years: 20 bar hostesses who had moderate or excessive alcohol consumption, and 16 women with a healthy alcohol consumption. The bar hostesses who drank excessively had an increased risk of menstrual flow abnormalities, higher levels of FSH, and fewer eggs in their ovarian reserve than their counterparts who drank significantly less alcohol. “This situation could lead to future infertility,” says Dr. Sharma.

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A study from the University of Massachusetts at Amherst found that smoking was strongly associated with the development of PMS. The heaviest smokers were found to be afflicted with a 2.5 times higher risk for severe PMS than women who had never smoked. “If women start at a young age and smoke half a pack to a pack a day, they will have a significantly increased risk of moderate to severe PMS,” says Dr. Sharma. The reason? Smoking and nicotine have a negative effect on the pelvic organs. “Smoking decreases oxygen delivery to the pelvic area so you can have pelvic congestion, more pain and worse PMS symptoms,” she says. Smoking can also cause the fallopian tubes to malfunction, a situation that can lead to infertility, and decreased egg quality and quantity. “Long-term smokers are going to have more infertility and poorer egg quality compared to non-smokers,” says Dr. Sharma.

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Body weight

“Body fat is closely related to hormonal production, ovulation and menstrual regularity,” says Dr. Sharma. “Rapid weight loss or weight gain will affect your menstrual cycle.” Women with a low body weight or a rapid weight loss have low cortisol levels that could result in the reproductive system “basically shutting off,” according to Dr. Sharma. “Their bodies don’t have enough fat to support pregnancy, so they ovulate less regularly,” she says. With limited ovulation, periods may be seldom or completely absent, or they might be longer than normal.

Overweight women often have long cycles too, but for a different reason. “Overweight and obese patients have longer cycles much like anorexic patients, but it’s because they have extra weight. Their bodies produce a lot of insulin – a hormone that affects the ovaries directly – and it suppresses ovulation,” says Dr. Sharma. To get their cycles back on track, Dr. Sharma recommends that underweight women gain a few pounds while heavy patients should lose some weight. “Even a five percent reduction in body weight can get obese and overweight patients to ovulate regularly,” she says.

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When to seek help

Brief cycle disturbances that last for a month or two are probably normal, but Dr. Sharma recommends that you see your family doctor or an OBGYN if you experience any issues that continue beyond that time frame. “Your doctor can assess other hormones like the thyroid – a big regulator of the menstrual cycle,” she says. When in doubt, it’s best to seek professional advice.

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