We’ve researched the heaps of food-related advice that frequently come with pregnancy and found most of it specious. Now, we’re looking into activities. Because suddenly, everyone has an opinion on what you should — but mostly shouldn’t — be doing, from swimming to sex during pregnancy.

Some of people expounding on things not to do during pregnancy are easy to brush off, like the ones who tell you not to drink coffee so your baby will be fairer. (Eye roll.) But some of these prohibitions have become so deeply ingrained that they have taken on a patina of medical objectivity, even though, upon closer inspection, they hold about as much water as the link between coffee and skin color.

In no particular order, here are some of the most commonly repeated prohibitions — and whether they actually matter.

Things not to do during pregnancy (except you actually can)

Dyeing your hair

While it’s true that prolonged exposure to toxic chemicals could harm a fetus, these substances are present, if at all, in such minuscule quantities in hair dye that there is no risk of harm to the fetus. In fact, very little of these chemicals would even get absorbed through the scalp in the hair dying process. So highlight away.

Being physically active during a “risky” pregnancy

The level of permissible weight gain and physical activity recommended by doctors seems to vary widely around the world. But one prescription seems to have persisted across cultures: The idea that laying horizontally will eliminate the risk of preterm labor.

But a recent study showed that in two groups of women with similarly risky pregnancies, there was absolutely no difference in the number of preterm births between the group that was on full bedrest versus the one that continued with normal physical activity. In short, there is no proof that bedrest prevents preterm labor.

In fact, some studies have even suggested months of total inactivity actually harms the mother and baby.

Keeping pets

Keeping a pet while pregnant is high on the lists of so-called things to avoid in pregnancy. But there is absolutely nothing wrong with keeping your pet parakeet around while you’re expecting.

The only possible problem with playing Doctor Dolittle during pregnancy is cat litter: There is an increased chance of getting infected with toxoplasmosis if you come into contact with cat feces. But as long as you’re a dog lover, or you steer clear of the kitty litter box, there’s no reason to start giving away your pets the moment you conceive.

Traveling by air

Flying is another one of those common-knowledge things not to do in pregnancy. But it’s all a misconception. The good news for your wanderlust is that there’s virtually nothing to these rumors.

Yes, the first trimester is when most miscarriages happen, but those do not occur because of a flight to Goa. (They occur for reasons almost entirely separate from your physical activity.) And while airlines do prevent women from flying in their final six weeks of pregnancy, that’s only because they don’t want the liability of women going into labor on flights.

As long as pregnant women move around frequently, to ensure their circulation is not affected, there’s nothing inherently more dangerous about sitting on a plane than sitting in a chair at home.

Swimming

We’ve heard people say swimming is not recommended for pregnant women. This one is easy: not true. Swimming is actually one of the best forms of exercise for pregnant women because it allows you to get all the benefits of cardio and strength training, without putting stress on your joints and spine. Enough said.

Having sex during pregnancy

People have hangups about sex during pregnancy for a variety of reasons, but if your concerns are medical in nature, rest assured that there is nothing dangerous about it. You will not harm the baby by having sex during pregnancy.

(Now, some studies have shown that sex during pregnancy in the third trimester can induce labor, so if you are at risk of preterm labor, you should see where your doctor stands on this debate; but for normal pregnancies, you can carry on with your bedroom shenanigans without worrying about the baby.)

Getting laser hair removal

Most women who swear by laser hair removal are devastated to find out that not only can pregnancy hormones reverse their previous attempts at permanent hair removal, but that they are not allowed to continue their removal routine while pregnant.

Here, there is some truth to the prohibition: While from a health perspective it’s perfectly all right to continue with laser hair removal while pregnant, the changes in a woman’s hormones during pregnancy mean the laser could have long-term skin pigmentation effects. So it’s perhaps better to tolerate a little extra hair in the short term.