Think you know all there is to know about your period? Women have about 450 periods during their lifetime, which means you have plenty of chances to learn all about it. Even so, your period can still manage to surprise you -- and not just by showing up when you least expect it. Did you know these five facts about your monthly visitor? 1. You can get pregnant during your period. It’s time to squash that age-old myth: Your period doesn’t protect you from pregnancy. There are a couple of reasons why. First, some women may bleed when their ovaries release an egg each month, called ovulation, and mistake it for their period. You’re at your peak fertility when you ovulate. So if you have sex during this time, it could actually make you more likely to get pregnant. Second, you may ovulate before your period is over or within a few days after the bleeding stops. Since sperm can hang out in your body for up to 3 days, having sex during your period could lead to conception. Use a condom or...