Moody and sweaty? It could be perimenopause

(CNN) - It's not always easy for women to accurately detect the symptoms of menopause, but one doctor knows what women should be looking for.

Maria Sullivan, 48, is approaching menopause and said her body is changing.

"The weight gain … all of a sudden 15 pounds just happens," she said. "The night sweats."

Sullivan said entering menopause has been stressful.

"I didn't know why I was having mood swings, I just knew that afterwards I was just angry for no reason."

Menopause is defined as the permanent end of menstruation and fertility. It usually occurs near the age of 51.

The time leading up to menopause, called perimenopause, is when the ovaries slow their production of hormones and stop producing eggs sometimes leading to symptoms including: hot flashes, hair loss, weight gain, mood swings, facial hair growth and vaginal dryness

"It affects bone density, osteoporosis becomes more common," said OBGYN Dr. Dale Bearman.

According Bearman, the weight gain may be more of a side effect of a slowing metabolism.

He recommends plenty of exercise, and maintaining a healthy diet rich in calcium and vitamin D to try to keep symptoms and side effects to a minimum.

If symptoms are severe, talk to a doctor about treatment options.

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