But as I grew up, started using the pill as a contraceptive, and became a scientist myself,

I started asking more questions about what exactly the pill is doing in our bodies. Because not only do I take it, but millions of other people around the world do too.

Now, there are a ton of different methods of birth control out there. We've got the hormonal ones, like the pill, IUDs, shots, implants,

and then the physical barriers like condoms and diaphragms. The list of choices is growing and frankly, it's kind of overwhelming.

So I figured we could focus on two of the most popular ones: the pill and the hormonal IUD,

both of which have a ton of interesting effects on the bodies of people who menstruate, some of which we're still figuring out.

Sometimes I think birth control can be a little bit of a mystery to some people.

About half of people who are on a birth control pill are on it for things other than pregnancy prevention.

When the birth control pill was first invented, part of its purpose was to be able to give the person

who was ovulating the power to decide what they wanted to do independent of their partner.

Dr. Stacy T. is right, this tiny but mighty pill prevents pregnancy, but it can also help the person taking it have more control over

lots of other things to do with their sexual and reproductive health. So how exactly does it work?

There are lots of different formulations of the pill, but the most common is the combination pill. If you've watched my video on menstrual cycles,

which you can check out now, you'll remember that two of the important sex hormones that influence fertility are estrogen and progesterone.

The combination pill contains synthetic versions of both of those hormones: those are called ethinyl estradiol and progestin.

When you take both of these together, what it does is it suppresses ovulation.

There's a couple of other secondary factors that it does as well, it might alter motility of the tubes themselves, and it might thin out the lining of the uterus.

Basically the pill makes it so no baby-making equipment is up and running. On top of that, the progestin in the pill thickens the mucus of the cervix.

And yes, your cervix naturally produces mucus, it's totally normal and healthy and cool, and by making that thicker, it acts as a 'no sperm allowed' zone.

So even if a sperm manages to get to the cervix, it would get stuck, kind of like a sticky trap for insects.

And yes. The pill does prevent pregnancy, but there are lots of other reasons to take the pill.

There are some other benefits and pleasant side effects that the pill can sometimes offer,

such as decreased bleeding with periods, decreased cramping with periods.

It can help treat acne, as my teenage self discovered, and in the long-term, research is also telling us that taking the pill can reduce our risk of

uterine, colon and ovarian cancers. And for those suffering from endometriosis or fibroids, conditions that cause really painful and really heavy periods,

the pill can provide relief by alleviating some of those symptoms.

Now, obviously, the birth control pill is not curing any of these conditions per se. It's meant to control symptoms.

Meaning, birth control isn't necessarily treating the root cause of an issue. And everyone is different.

So, while some people do get huge benefits out of taking it, the crappy side effects of birth control aren't talked about as much.

Things like headaches, breast tenderness, or nausea. And one reason why these side effects happen is the hormones in the medication are synthetic.

They mimic your natural ones, but they don't 100 percent match them. And that's why the pill's side effects are a little different

from the effects of, say, just the natural progesterone that your body produces.

And just by taking these synthetic hormones, the symptoms of your menstrual cycle may be amplified.

And in the long term, there are still some unanswered questions about birth control. Like what effect can these hormones have on mental health?

What effect does the pill have on our vaginal microbiome? And some of the side effects we do understand relatively well can be really serious,

like the increased risk of blood clots, but we'll get more into that later.

Because, to be most effective, the pill has to be taken daily around the same time so that the levels of these hormones in your body are kept nice and steady.

So what about the other popular contraceptive we mentioned?

The intrauterine device, or the IUD, is implanted directly into the uterus, which sounds a little intimidating

but IUDs fall under the category of LARCs, or Long-Acting Reversible Contraceptives. These little “t” shaped devices come in two main flavors: hormonal and copper.

And it's a favorite for those who want a more low maintenance option. Because once it's in the uterus, you can keep it there for years,

depending on which one you get, and you don't really have to give it much thought. The hormonal IUD's lifespan can be anywhere from 3 to 7 years,

depending on the brand. And apart from abstinence, LARCs are one of your best non-permanent bets to avoid pregnancy,

because they have more than 99% efficacy rate.

So how exactly does it work? The hormonal IUD is constantly releasing a small amount of progestin into the uterus

while it's chillin' up there, so it's a localized hormone delivery as opposed to the pill, which is releasing its hormones system-wide via your bloodstream.

And like the pill, the IUD's progestin thickens the mucus of the cervix. The hormonal IUD does also come with a “fun” array of side effects:

things like irregular bleeding patterns, headaches, cramping, bloating

but typically, these are supposed to go away about 3-6 months after insertion.

There are also very rare cases of complications, like the device causing damage to the uterus, or your body can choose to just expel the IUD entirely

like, just yeet it out of your uterus, but again, these are very rare.

So as you can see, these two popular choices, the IUD and the pill, are far from perfect.

And remember that increased risk of blood clots? Here's the sitch on that.

We know that the increased risk of blood clotting is mostly from the estrogen components, because estrogen is thought to be what we call pro-thrombotic.

That essentially means that your blood is more likely to clump together into clots. And these can be dangerous because

they can block blood flow to other parts of your body. Research suggests that the synthetic estrogen in the pill is what's increasing

certain blood clotting factors, while also decreasing anticoagulants, or the substances that can thin out your blood,

all of which together makes a big, blood, roadblock more likely.

So the higher estrogen state, the higher that risk is. So when birth control pills were first invented, and the dosages were significantly higher,

that risk was much higher. And as we've moved down those dosages, that risk has become lower.

There are also cases where some kinds of progestin have been linked to blood clots, but we still need more research into that.

Like Dr. Staci said, those cases are rare, but this is why it's really important to be aware of the risks before choosing a birth control method,

especially within the context of your personal health history, because some individuals may have a higher baseline risk to begin with.

And how about the long-term impact of taking synthetic hormones?

I think a common misconception about birth control pills, in general, is that it can affect long term health overall.

Most of the risks and side effects involved are more immediate when you're taking it and for some of them, for the short period after you're taking it.

I think it's important to take a minute here and recognize that while birth control has changed the world and so many individual lives for the better

it's not as good as it could be. And yes, it lets those of us who ovulate have more bodily autonomy. We get to decide if and when we get pregnant

which is arguably one of the most important decisions for our lives and our health, and one that used to be much more out of our hands.

But the burden of birth control, the cost, the responsibility, and certainly the health risks, still mostly rests on the shoulders of the person

who can get pregnant, and they might be left with lots of questions, or stuck between choices that may not be quite right for them.

Because aside from the pill and the IUD, there are a ton of other options out there, and each comes with their own pros and cons.

One of the most common questions that I get all the time, is what is the best form of birth control?

And that question is really difficult because it's different for each individual person, because everyone has different priorities.

Everyone has a different health background.

Everyone has different ideas of if they want to prevent pregnancy, or if they want to treat symptoms of something else.

So best is not really a generalizable thing. It is what is best for you and your personal priorities.

My hope is that the more we talk about our existing birth control options, like which parts work and which parts don't,

and ask for more research into some of the side effects we still don't have a clear picture on, then the science world may be motivated

to come up with better and better options. And who knows, male birth control may become a reality sooner rather than later, and that would be rad!

The upshot is, I hope learning more about the ins and outs of your own bodily cycles and how birth control works within those

can give you the power to take your time. Talk to your healthcare provider, ask questions, do your own research, and make informed decisions

about what's best for you and your goals. Good luck out there.

I know it's tough but now at least you have some info to get you started.

Thanks for watching Seeker's new series Body Language. I hope you've enjoyed this video.

And if there's another women's health topic you want us to cover, leave us a comment. I'll see you next time!