Pregnancy during hot weather and heatwaves

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

Because of this, if you are pregnant you need to take extra precautions to avoid overheating on hot days or during heatwaves, which can make you feel unwell and can affect you 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 your blood vessels to narrow as your body tries to cool down, reducing the amount of blood and nutrients that pass through to your 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 when you can in a cool, darkened room.
• 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.
• Sitting with your feet in the water of a shaded paddling pool is a good way to cool down, as well as keeping watch if you have other children enjoying the cool 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.
• Limit salt and caffeine as they can contribute to dehydration.
• Completely avoid alcohol, which contributes to dehydration and isn't safe for your baby.

Ice cream and icy poles

• Avoid soft-whipped ice creams (eg. from soft serve machines) as they are higher risk for Listeria bacteria.
• Avoid homemade ice cream that may be made with raw eggs.
• Homemade icy poles or ice blocks and shop bought ice cream or icy poles are fine to eat.

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. 
• 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 that covers 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.

Exercise

• Reduce your level of exercise and opt for low-intensity activities during hot weather, to avoid raising your body temperature too high. 
• Consider activities like swimming, walking in the early parts of the morning or in the evening when temperatures are cooler, or gentle stretching exercises.
• Stay hydrated and drink plenty of water before, during and after exercise.
• Avoid overexertion, take regular breaks and pay attention to how you feel and stop exercising if you feel unwell.

Getting help if feeling unwell

If you feel like you have overdone it during the heat

• Stop what you are doing and rest 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.

For more information

Learn more about hot weather and heatwaves

Find out more about coping in a heatwave from Healthdirect website