You’re avoiding drinking alcohol and eating anything you can’t pronounce; you’ve limited your caffeine and even stopped taking your usual pain medication for headaches. But do you also need to literally keep your cool to protect your growing baby?

Yes — to a degree (no pun intended). Medical research shows that overheating during pregnancy can put your baby at risk. Health guidelines advise that getting your core body temperature at or over 102°F (39°C) can be too hot for your little one (and for you, too!).

But also, it’s normal to feel somewhat warmer when you’re pregnant — you really do have a bun in the oven. Several body changes during pregnancy can slightly raise your body temperature, and that’s completely fine. It’s when you’re exposed to too much heat that you can feel unwell and it can affect how your little one develops.

According to medical studies, heat stress can cause problems with how a baby’s spinal cord and backbones develop. These complications are called neural tube defects.

Fortunately, even though you may feel hotter, it’s fairly difficult to raise your body temperature to harmful levels — even during pregnancy.

That pregnancy glow is very likely part joy and part flushing from heat. You’re not imagining it — every stage of pregnancy can slightly raise your body temperature. Your skin may feel warmer to touch. You’re likely sweating more and may even have night sweats.

At the beginning of your pregnancy, new hormones are like little workers that help keep everything humming along smoothly. These hormonal changes also raise your body temperature a small amount. (Plus, they sometimes cause side effects like morning sickness — but that’s a whole other article.)

Several other changes happen as your body prepares to grow and nourish new life. More blood is needed to carry food and oxygen to your baby. In fact, your blood volume increases by up to 50 percent by week 34 of pregnancy.

The heart keeps up by working harder than it already does. By the eighth week of pregnancy, your heart is pumping blood 20 percent faster. A higher heart rate raises metabolism, which also slightly spikes your body temperature.

Blood vessels throughout your body widen to deliver all this blood. This includes the blood vessels near your skin. More blood flows to your skin — causing you to flush (or glow) and making you feel warmer.

By the third trimester, carrying your baby also means carrying around your personal built-in heater. Your growing little one gives off body heat that you absorb. This can make you feel hotter from the inside out. Pregnant with twins? Yes, you have two little portable heaters of joy.

Simmering in a hot tub might sound relaxing to your aching pregnant body, but it’s best to cool off in a pool instead. Pregnancy and hot tubs don’t mix.

If you do want a dip in a hot tub, experts say limit it to 10 minutes only. Staying in a hot tub longer can raise your body temperature over 101°F (38.3°C).

Read more: Hot tubs and pregnancy

The same goes for dry or wet saunas. Overheating can occur if you stay in a sauna for too long. Medical research found that most women at any stage in their pregnancy can safely stay in a 158°F (70°C) sauna for only up to 20 minutes without overheating.

Again, if you always feel hot or unwell while in the sauna, it’s best to get out immediately or avoid saunas entirely during your pregnancy.

A bath at home may not be as hot as a hot tub or sauna, but you still need to avoid hot water. Stick to a warm bath instead. The water shouldn’t be steaming, just warm enough to be comfortable. Keep a window open in the bathroom to keep things airy and cooler.

A heating pad or a hot water bottle can help soothe muscle pain right where you need it. It’s OK to use one occasionally while you’re pregnant. But it’s best to avoid using it near your stomach — you don’t want to directly heat up your baby. There is danger to heating up the belly.

Make sure the heating pad is a comfortable temperature. Too hot and it can scald your skin. Use a towel or soft cloth between the heating pad and your body to avoid too much heat.

You can also spot treat areas with a heating pad. Rest your tired feet on one or soothe back pain. Never use a heating pad while sleeping. If you think you might fall asleep during heat therapy, unplug it first!

Heat exhaustion and heat stroke can happen to anyone in very hot weather or during strenuous exercise. The hot sun can make you overheat and cause serious health problems. When you’re pregnant, it’s even more important to stay cool on a hot day.

If you must be outside in hot weather, try these tips to cool down you and your baby:

  • wear a hat or cover your head
  • carry a water bottle to stay hydrated
  • carry a wet towel to wipe down
  • use a sun umbrella for shade
  • wear loose clothing
  • wear cotton or other natural, breathable fabrics
  • keep your skin covered
  • avoid exercising outside

While hot flashes during pregnancy are usually hormonal, you might have some triggers that you can control. Keep a journal of when you have hot flashes to find out what might set them off. Triggers include:

  • hot drinks
  • caffeine
  • spicy foods
  • tight clothing
  • warm room
  • anxiety
  • stress

Ask your doctor to check your hormone levels. This involves a simple blood test. Some common health conditions like hyperthyroidism can also cause hot flashes and overheating.

Keeping cool during pregnancy is only a little different than keeping cool when you’re not pregnant. Protect yourself and your baby from heat stress by avoiding very hot temperatures. You know the drill — stay out of the sun and avoid hot tubs, saunas, and very hot baths.

Other ways to keep your cool include:

  • stay hydrated — keep a cold water bottle with you all the time
  • keep clear of the kitchen on warmer days — let your family cook for you
  • avoid working out or exercising in closed, hot rooms — and no hot yoga during pregnancy
  • keep your bedroom cool while sleeping — crank up the a/c or use an electric fan on very hot nights
  • avoid too much bedding and wearing warm pajamas to bed
  • splash cold water on your face and body to refresh
  • soothe your tired feet in a cool water bath
  • get a relaxing massage instead of using heating pads for aching muscles

Some studies show that a bit of heat is good for your baby. Medical research found that seasonal temperatures affect birth weight and length. The researchers found that babies born during warmer months were longer in length. Mothers in warmer climates during the middle of their pregnancy had heavier babies.

Feeling warmer and having night sweats can be a normal part of a healthy pregnancy. Your slightly raised body temperature means you have to be extra careful when going out on hot days and during strenuous activity.

Avoid hot tubs, saunas, and other activities that warm you up too much. Heat stress can be harmful for your baby.

Tell your doctor if you feel that you’ve overheated during pregnancy. If you have night sweats along with other symptoms, you might have health complications like an infection. See your doctor urgently if you also have:

  • a fever higher than 101°F
  • nausea
  • flu symptoms
  • muscle aches
  • diarrhea