Pregnancy during extreme heat

Most women experience an increase in body temperature during pregnancy and this makes them more sensitive to high temperatures.

Because of this they need to take extra precautions to avoid overheating on days of extreme heat, which can make them feel unwell and can affect them more severely than the average adult.

Several studies have suggested that during the first 12 weeks of pregnancy, developing babies can be affected by the heat. Getting hot causes a mother’s blood vessels to narrow as she tries to cool herself down, reducing the amount of blood and nutrients that pass through to her baby.

Keeping cool

Keep in mind that if you are getting overheated so is your baby, and this can be dangerous for the baby.

• Rest or take a nap when you can in a cool, darkened room.
• Invest in a cooling leg gel and take regular breaks to sit with your feet up in front of a fan or in an air-conditioned room.
• Place a bowl of ice cubes in front of an electric fan for a cooling breeze.
• Have a spray bottle filled with water to cool your face and body.
• Place a wet face-washer or towel on your head or neck, or fill a bowl with cold water to put your feet in.
• A lukewarm shower or bath can help during the day. At night it can be soothing and may help you get a more restful night’s sleep.
• If you have another child, sitting with your feet in the water of a shaded paddling pool is a good way to cool down, as well as keeping watch while your child enjoys the cooling water.
• Avoid going out in the hottest part of the day, usually mid to late afternoon. Limit trips or shopping when temperatures are at their highest.

Drinking and eating

• Drink frequently throughout the day to prevent dehydration. Your body needs more fluid than usual when pregnant, especially in hot weather. Don’t wait until you are thirsty as you may be dehydrated by then.
• Always carry cold, bottled water with you when you go out.
• Choose a variety of foods including plenty of fruit and vegetables. Eat lighter meals such as salad, but avoid pre-prepared salads (learn more about eating well during pregnancy).
• Limit salt and caffeine.
• Completely avoid alcohol. Even in small amounts, alcohol will enter your baby’s bloodstream and this can affect the development of your baby, especially their brain.

Ice cream and icy poles

• Avoid soft-whipped ice creams (from ice cream vans and fast food outlets) as they can contain bugs such as salmonella, which can grow rapidly during hot weather if the equipment is not kept clean.
• Avoid homemade ice cream with raw eggs should also be avoided.
• Ice cream from a supermarket is fine to eat.
• Homemade icy poles or ice blocks from frozen fruit are fine to eat.

Other foods to avoid eating while pregnant are those which may contain listeria, a common bacteria that can cause severe illness. If consumed during pregnancy, this may cause miscarriage, stillbirth, and infection in your unborn baby.

Learn more about eating well during pregnancy

Clothing and sun protection

• Wear comfortable, lightweight, loose-fitting and breathable clothing made from natural fabrics (cotton or linen) that can absorb perspiration. Avoid synthetic fabrics which don’t breathe and can make you feel hotter.
• Don’t spend too much time out in the direct sun and try to stay in shady areas. Wear sunglasses and a wide-brimmed hat (at least 7.5cm wide), or a legionnaire or bucket-style hat. Make sure it shades your face, neck and ears.
• Always wear broad-spectrum sunscreen (minimum SPF30+) when outdoors. Re-apply every two hours, especially if you are spending time in the water. If you find that your skin is more prone to irritation when using sunscreen during pregnancy, try a brand specifically for sensitive skin.

Exercise

• Talk to your doctor before starting any exercise program during your pregnancy and work out what forms of exercise are best for you.
• Avoid exercise in hot weather, as this will raise your body temperature further. Remember that the hot weather will only last for a few days, and you can return to your normal exercise routine once the weather cools.
• Gentle swimming in a non-heated pool may be a suitable form of exercise as it will not only keep you cool but will help take the extra weight off your joints for a little while. Avoid spas as they can increase your body temperature at a time when your circulatory system is already providing greatly increased blood flow in support of your pregnancy.

Getting help if feeling unwell

If you feel like you have overdone it during the heat

• Stop what you are doing and lie down in a cool or air-conditioned room.
• Lie/sleep on your side (left preferably) as this will increase the amount of blood and nutrients that reach the placenta and your baby.
• Don't sleep on your back (this can make you feel dizzy or faint)

If you feel dizzy, light-headed, short of breath, or your symptoms get worse then call your GP, obstetrician, midwife or the maternity unit where you are to give birth.