Scarleteen

I'm just trying to find out a little bit about what exactly the period does..

I know when you have a period it is shedding the liner.. So if you have sex two or three days before your period but then you get your period, does that mean that you couldn't get pregnant from that sex you had? My friend and I were discussing this and I wasn't sure so I figured you guys would know.

It's very unlikely anyone would become pregnant from sexual activity 2 or 3 days before they then had a period. The reason for that is how different hormones work at different times in the menstrual cycle: a very different balance of hormones is needed in the body for it to become pregnant than the balance of hormones that immediately precedes and triggers a period. So, if someone starts their period, they can know their body wasn't able to become pregnant 2 or 3 days previously, because they couldn't have been in the right place in their menstrual cycle.

You can find out more about hormonal changes during the menstrual cycle from On the Rag: A Guide to Menstruation

If someone's using hormonal contraception, obviously they won't have exactly the same hormonal patterns as someone who isn't (and if they're using it correctly, pregnancy is unlikely at any time). The general principle remains the same, though: the hormone combination needed to make pregnancy possible and the combination that results in a bleed are different and can't happen at the same time.

The one very important thing not to do is to assume your period will happen when you expect it to and that just before that time won't have much pregnancy risk. Even for the most regular people, sometimes a cycle can be later than usual; and unless you've been charting physical signs carefully every day for months, you just won't know, and that's one way unintended pregnancies happen.

Thank you for the reply! I never considered the changing of hormones, but I'm on birth control pills. My understanding was if you have a period then the shedding of the lining made it to where nothing could implant. Is bleeding during the placebo pills the same thing as a "period"? I've heard it called withdrawal bleeding before.

The bleeding you have during your placebo pills is indeed called a withdrawal bleed! Many people do call it a period, since it is also the shedding of the uterine lining and often feels similar to how a period feels, but "withdrawal bleed" is the proper term.

But really it is the same thing pretty much?

In terms of what it is, how it feels to most people, and what it means (in terms of pregnant people not having withdrawal bleeds the same way they don't have periods), it is very similar, yes.

If you go on vacation and the time changes by an hour does that make a difference when taking birth control pills? Say for instance I take my pill every night at 9:30 but when I go on vacation the time is 1 hour ahead.. Would my pill be less effective if I take my pill at 9:30 my vacation time (so at home it's 8:30)?

Hi smoore188,

With the pill, you have a 12 hour grace period before it is even considered late, so an hour difference should not decrease the effectiveness.