Why am I more affected by hot weather when pregnant or breastfeeding?

During pregnancy and breastfeeding, your metabolism increases to support your baby and milk production. This causes your body temperature to rise, which can make you more sensitive to hot weather.

​​​​​​​Can hot weather affect my baby when I'm pregnant?

In the first trimester of pregnancy, becoming overheated can affect your baby's growth and development.

If you become overheated, more blood flows to your skin to help you cool down. This may mean less blood goes to other parts of your body including your placenta. The placenta supplies your baby with oxygen and nutrients.

​What is heat exhaustion?

Heat exhaustion can happen when you lose a lot of fluid from your body. It's often caused by excessive physical activity or being in a hot environment.

Symptoms of heat exhaustion include:

• excessive sweating
• feeling very thirsty
• a headache
• muscle aches and cramps
• dizziness
• increased pulse
• pale and clammy skin

Dark-coloured urine (wee) is a sign of being dehydrated.

Heatstroke

Left untreated, heat exhaustion can become heatstroke. Heatstroke requires immediate medical treatment, as it can be life-threatening.

​How is heat exhaustion treated?

Self-care at home

Here are some ways to reduce the symptoms of heat exhaustion:

• Lie down in a cool and shady place.
• Loosen any tight clothing and remove as many layers as possible.
• Place your hands and feet in cool water, or wet your skin.
• Sit in an air-conditioned room or use a fan to cool down.
• Drink regular sips of water.
• Limit physical activity, especially outdoors.
• Avoid drinks that can dehydrate you, such as soft drinks, alcohol and coffee.

When to see a doctor

Short periods of feeling hot and uncomfortable are often unavoidable during the summer months.

You should see a doctor if your symptoms of heat exhaustion do not improve after you move to a cooler place and rest.

See a doctor or visit an urgent care clinic if you develop symptoms such as:

• dizziness
• nausea
• a rapid (fast) pulse
• shortness of breath

FIND A HEALTH SERVICE — The Service Finder can help you find doctors, pharmacies, hospitals and other health services.

​​​​​​​When to seek emergency care

Get emergency medical care if you are experiencing symptoms of heatstroke, such as:

• hot, dry skin with no sweating
• sudden rise in body temperature to more than 40 °C
• severe dehydration
• rapid breathing
• vomiting
• confusion or slurred speech
• loss of consciousness or seizures

How do I stay cool and avoid overheating during pregnancy and breastfeeding?

It's not always possible to avoid becoming overheated, especially during periods of extreme heat.

Here are a few things you can do which may help:

• Avoid being in the direct sun — stay inside or in shady areas.
• Use spray bottles filled with water to cool your face and body.
• Place a wet washer or cooling wrap around your head and neck.
• Put your feet in a bowl of cool water. You can also place your hands in cool water.
• Have a cool bath or shower.
• If you can, go somewhere that has air conditioning during the middle of the day.

Extreme heat

Extreme heat is when the maximum and minimum temperatures are unusually hot for 1 or 2 days. In Australia, periods of extreme heat are:

• becoming hotter
• lasting longer
• happening more often

In rural or remote areas, extreme heat can impact your access to transport, services and the safety of outdoor activities. Try to plan ahead — limit travel and outdoor tasks during the hottest part of the day and allow time for rest between activities.

What else can I do to avoid overheating when breastfeeding?

Here are some strategies to keep you and your baby cool when breastfeeding:

• Place a cotton wrap between you and your baby.
• Lie down to feed so there's some space between your baby's body and your own. Only your baby's mouth and your breast need to be in contact when breastfeeding.
• Place a cool wet washer in the crook of your arm.
• Breastfeed in air-conditioned spaces or use a fan to circulate and cool the air.

Making breast milk uses extra fluid, so you will need to drink more water than usual to stay hydrated. This is especially important during hot weather.

​Can I continue to exercise during hot weather?

You don't need to stop exercising when it's hot, but you should consider the type of exercise you do and when to do it.

Exercising early in the morning or later in the day when the air is cooler means there's less risk of overheating. It's also important to choose activities that are less likely to make you overheat from working too hard.

Activities that are less likely to cause overheating include:

• swimming or other water based exercises such as aquarobics
• walking
• pregnancy exercise classes
• gentle cycling — either outdoors or on a stationary bike
• pilates, yoga or stretching

Most people should aim for at least 30 minutes of moderate intensity physical activity on most, if not all, days of the week.

​​​​​​​Sun protection and sunscreen

Using sunscreen is advisable at all stages of life, including during pregnancy and when breastfeeding. Although sunscreens contain various ingredients, the amount absorbed through the skin is thought to be minimal.

Use a sunscreen that is suitable for sensitive skin and is hypoallergenic if you are prone to skin reactions. Speak to your pharmacist if you need help choosing a sunscreen that is right for you.

Wear sunglasses and a wide-brimmed hat that covers your face, neck and ears when outside.

​​​​​​​Resources and support

Read more about how to deal with hot weather on the Australian Centre for Disease Control page.

The Australian Breastfeeding Association offers information on:

• how to safely breastfeed during hot weather
• breastfeeding friendly venues
• breastfeeding when pregnant

Speak with your doctor or maternity care provider if you need more information about pregnancy and breastfeeding in hot weather.