in your 30s
BY THIS POINT, you’ve probably had your period for almost two decades, and, unless you’ve been pregnant, it likely hasn’t changed much since your late teens. A typical cycle lasts between 21 and 35 days, counting from the first day of your period up to (but not including) the first day of your next period.
That cycle is made up of two phases: The follicular phase starts on the first day of your cycle and lasts until ovulation day, when the luteal phase, which begins once the ovary releases an egg, takes over. Because the luteal phase almost always lasts about 14 days, you can estimate the date of your last ovulation by counting backward from the end of your cycle. For example, if your cycle was 30 days, you likely ovulated on Day 16.
In general, menstruation lasts four to seven days. But don’t worry if that number fluctuates somewhat, says Dr. Melissa Mirosh, an ob-gyn in Saskatoon. You’re still in the normal range if, one month, your period arrives on Day 26 and lasts for five days, and, next month, it doesn’t come until Day 31 and it lasts for seven days. But if the duration of your period or cycle varies more drastically, there could be a problem. “The concern is that, if the cycle isn’t normal, it could be because of an underlying medical issue or it could affect fertility potential,” says Dr. Suzanne Wong, an ob-gyn at St. Joseph’s Health Centre in Toronto.
PREPARE FOR: PREGNANCY Women who have irregular periods and are trying to conceive can have a rough go of it. “Predicting ovulation becomes harder when cycles are irregular, which makes achieving pregnancy more difficult,” says Dr. Wong. Pregnancy can also affect what happens with your period postpartum. “After having a baby, when your hormones are still getting back to their usual routine, it can be quite normal to have chaotic cycles for six to 12 months,” says Dr. Waddington.
Most women who breastfeed will resume menstruating six to nine months after delivery; those who don’t may ovulate as early as three weeks after delivery and menstruate five weeks postpartum. “This is important to consider if you’re resuming sexual activity, because you can get pregnant quite soon after delivery,” says Dr. Waddington. And about that post-pregnancy period: There’s no way to tell if it will be heavier or lighter than before, but many women who experienced excruciating cramps prepregnancy find that the pain has subsided, perhaps thanks to stretching of the uterus during those nine months.