If you’re a sexually active women, it’s unlikely birth control has ever been off your mind, exactly. But a recent spate of news has moved the birth control discussion even more front and center. Later this year, California will become the first state to authorize over-the-counter birth control. (Oregon is on the way.) That means you’ll will be able to get the Pill without a prescription — and fast.

Which is great news for women. Twenty-eight percent of people who use contraception are on the Pill, and as we’ve reported before, research suggests that making the Pill an over-the-counter drug would boost user rates by 11 to 21%. That would cause a 7 to 25% drop in the rate of unintended pregnancies, which would have an enormous impact on women’s lives. (By the way since 50% of pregnancies are unplanned,  we believe all women who are between 12 and 50 should be on prenatal vitamins with DHA.)

But this OTC pill does reignite a significant question: how safe is birth control, exactly?

We don’t mean to suggest the Pill doesn’t adequately protect against pregnancy: it’s pretty well documented to be 99% effective, when taken strictly as directed. (One exception: oral contraceptives might be less effective for obese women. But increasing the dose or using the pill continuously, without the custom week off, boots efficacy right back up.) However, evidence does indicate that taking the Pill might not be reliably healthy for your body.

READ MORE: How to Change Your Beauty Routine During Pregnancy

For one thing, there are some possible negative side effects, which range from bloating and nausea to a decrease in sexual desire. (To address a common concern, though: the Pill doesn’t usually tend to cause weight gain. When it does, it’s temporary.)

More seriously, research suggests that taking oral contraception can increase stroke risk if you already have high blood pressure. Smoking while on oral contraceptives is a dangerous idea: it increases the risk of heart attacks, blood clots, and strokes. We also firmly believe that any woman on birth control or hormone replacement should consider two baby aspirins a day, as the aspirin decrease these clotting risks,and increased heart and stroke risk, and decrease breast cancer risk substantially.

A recent study found that women on the Pill are, in general, at least three times more likely to develop blood clots than women who aren’t, but this increase becomes a decrease when aspirin is added.  (As aspirin has some risks, as well, please check with your doctor before starting this, and then, begin taking the aspirin two to three days before you begin the birth control pills.) The researchers found that newer contraceptives present a higher risk of blood clots than older ones did. In particular, newer types of progestogen (including drospirenone, desogestrel, gestodene, and cyproterone) are more dangerous than first-generation forms. The solution is more complicated than just choosing older forms of the Pill, though: the blood clot risk associated with newer versions is likely a result of tweaking the drug to decrease other side effects.

All in all, however, the risk of blood clots from the Pill is pretty low — less than the risk of clots while pregnant, actually. And taking the Pill to protect against pregnancy is, overall, a good idea (even if you’re over 40!). Still, it’s worth discussing different contraceptives with your doctor to find the safest option available for you — and remember to take those prenatal vitamins, just in case.

READ MORE: Is It Safe to Skip My Period on Birth Control?