Many women find it embarrassing to complain about every ache and pain, and end up leaving their doctors in the dark about how they're really feeling. We asked Dr. Jerilynn C. Prior, scientific director at the Centre for Menstrual Cycle and Ovulation Research in Vancouver, and Dr. Kymm Feldman, family physician at Women's College Hospital in Toronto, what symptoms you should always tell your doctor about.

Skipping periods
If you just started your period or are age 45 or older, it's normal to skip periods.

"But if a woman who has been menstruating regularly misses a period, she needs to know why and needs to realize it carries a risk of bone loss," says Prior.

Thinning bones can lead to osteoporosis and eventually bone fractures. While missing a period now and then isn't a major concern, you should tell your doctor if it happens frequently. The problem may be that you don't weigh enough to be menstruating properly.

Heavy menstruation
Speak to your doctor if you're having heavier-than-usual periods, especially if they're outside of your regular cycle. Heavy menstruation may lead to iron deficiency anemia, which can play havoc with your productivity, feelings of self-worth and ability to exercise, says Prior.

According to Feldman, increased menstrual flow may be a result of infection or a symptom of hypothyroid, a condition in the thyroid gland that controls the body's metabolism. There's also a small chance that heavy menstruation outside of your regular cycle might be a sign of uterine cancer.

Change in your period pattern
Be mindful of your monthly flow, including how it usually feels and how strong your cramps normally are. If your menstrual cycle has been delayed and heavy bleeding follows, it might mean that you've had a "spontaneous miscarriage and need to see a doctor," explains Prior.

Some women brush off bleeding outside of their regular period days, excusing their bodies by saying they were simply "stressed out" that week. However, "stress doesn't really cause bleeding," says Feldman. "Bleeding outside of your cycle isn't generally normal and you should talk to your doctor about that."

Having your period outside of your regular cycle could be a sign of a thyroid problem or a sexually transmitted infection or tubular pregnancy if you have had unprotected sex.
Breast tenderness
"Front of the breast tenderness means high estrogen, and unusually high estrogen levels mean not enough exercise, weight gain or something that's disturbing your cycle," explains Prior.

Every woman's breasts feel different, says Feldman, and it's important to identify what your normal is when it comes to soreness. Sometimes tenderness in the breasts can be a result of something in your diet.

"Some women just experience more sore breasts than others and they find they can regulate that," she says. "It can be related to having too much caffeine."

Unexplained weight loss or gain
If your sudden weight change is not the result of increased exercise or depressive eating, it could be a thyroid issue, says Prior.

"If it's an overactive thyroid, you'll likely feel too hot and recognize that you're inappropriately hungry," she says. "In other words, you're eating many more calories than usual, yet still feel hungry all the time."

Blood in urine or stool
"The most common end to [blood in the urine] is a urinary tract infection," says Prior. "With blood in the stool, it's most likely hemorrhoids, but it could also be colon cancer."

By the same token, Prior says that occasional mid-cycle vaginal spotting is not that uncommon and is usually not a serious issue. 

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