Overheating during pregnancy and postpartum: What you can do to keep cool

During pregnancy and nursing, it is totally normal for mum to feel hot and uncomfortable due to hormonal changes that stimulate milk production. Can you stop night sweats and hot flashes for a cooler, happier mum and baby?

Pregnant woman on yoga mat

Some steps along the breastfeeding journey are well known, but postpartum night sweats and pregnant hot flashes aren’t always talked about. If you’re experiencing either of these, there’s no need to worry. It’s normal for a pregnant mum’s body temperature to increase by one degree Celsius during pregnancy1, which can lead to discomfort and the dreaded sweats. As many as 35% of women suffer from hot flashes during pregnancy, while 29% continue to experience them after delivery2. So if your body temperature is keeping you up at night, rest assured you’re not alone.

What is causing your night sweats and hot flashes?

A rise in the level of pregnancy hormones like progesterone and prolactin travelling around your body can cause a surge in your resting body temperature3. This leaves you feeling hot during the day and can cause pregnancy night sweats. Increased blood flow in the breast area during this time can also contribute to discomfort and sweating in early pregnancy. Body fat and plasma volume both rise by the seventh week of pregnancy4, which could be another factor responsible for a higher temperature.  

Higher body temperature is normal during pregnancy and postpartum

Scientific studies have shown that breast skin temperature increases by a further one degree Celsius after your baby arrives1. This can lead to further postpartum hot flashes and discomfort (which can be easily mistaken for a fever), and typically lasts up to six weeks post-birth. Studies of lactating women have also shown increased breast skin temperature5 and increased mammary blood flow during a breastfeed6.  All of this can contribute to that hot and bothered feeling that so many pregnant and nursing mothers will recognise straight away.
You might be wondering, “how long do postpartum sweats last?” Well, there is no precise start or end date – all mums will experience things differently. However, we do know that your increase in body temperature is all for your baby’s benefit.

How it benefits your breastfeeding

The increased blood flow through your boobs might make you feel uncomfortable at times, but it also ensures you are able to produce the optimal amount of milk to feed your little one. Your blood flow will remain elevated throughout your nursing journey and then rapidly fall back to pre-pregnancy levels after you stop breastfeeding7
Your areola is even warmer than the rest of your breast tissue, but this warmth helps your baby locate it in order to feed8
Incredibly, your baby’s crying can also trigger heat in the areola9, meaning your milk is ready to flow when you offer them your breast.

Can you do something to stop sweating?

There are a number of easy steps you can take to combat overheating and sweating during nursing or pregnancy. These can be as simple as drinking more water or drawing the blinds and seeking shade from the sun to help regulate your temperature during the day.

Taking cool showers in the morning and evening can also help to reduce overheating, while keeping the windows open at night to let cool air in can ease those late-night sweats.

Wearing loose, light, and breathable clothing can also make a real difference, and our Keep Cool™ bras will also help ease your discomfort. Designed with specially knitted breathing zones that allow air circulation, they will reduce your postpartum sweating and keep you feeling fresh.  
The Quick Dry Technology embedded in our moisture-wicking fabrics works to move sweat away from the body when you start feeling like you are going to overheat. At the same time, the 4-way Adaptive Stretch™ grows with you – extending from pregnancy and through nursing, offering you gentle support while ensuring your comfort. Our bras are also wireless and seamless. That makes them soft to the skin, provides a lightweight feel, and leaves zero pressure on the sensitive areas of your breast. 
There are three different bras in the Keep Cool™ range, so you can be certain to find the perfect fit for you: 


1 Burd LI et al. The relationship of mammary temperature to parturition in human subjects. Am J Obstet Gynecol. 1977; 128(3):272–278.

2 Thurston RC et al. Prospective evaluation of nighttime hot flashes during pregnancy and postpartum. Fertil Steril. 2013; 100(6):1667–1672.

3 Moghissi KS et al. A composite picture of the menstrual cycle. Am J Obstet Gynecol. 1972; 114(3):405–418.

4 Clapp JF et al. Maternal physiologic adaptations to early human pregnancy. Am J Obstet Gynecol. 1988; 159(6):1456–1460.

5 Kimura C, Matsuoka, M. Changes in breast skin temperature during the course of breastfeeding. J Hum Lact. 2007; 23(1):60–69.

6 Janbu T et al. Blood velocities to the female breast during lactation and following oxytocin injections. J of Developmental Physiology. 1985; 7(6):373–380.

7 Thoresen M, Wesche, J. Doppler measurements of changes in human mammary and uterine blood flow during pregnancy and lactation. Acta Obstet Gynecol Scand. 1988; 67(8):741–745.

8 Zanardo V, Straface, G. The higher temperature in the areola supports the natural progression of the birth to breastfeeding continuum. PLoS One. 2015; 10(3):e0118774.

9 Vuorenkoski V et al. The effect of cry stimulus on the temperature of the lactating breast of primipara. A thermographic study. Experientia. 1969; 25(12):1286–1287.

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