Postpartum Night Sweats: Why They Happen and How Long They Last

Yes, postpartum night sweats are a real and common thing. Waking up in a damp nightdress in the first weeks after delivery is usually your body adjusting to a sudden drop in pregnancy hormones and getting rid of extra fluid. They are typically worst in the first two weeks and fade as your hormones settle, although breastfeeding can keep them going a little longer. The kind of sweating that is not normal comes with a fever, chills, pain, or a general feeling of being unwell.

What are postpartum night sweats?

Cleveland Clinic defines postpartum night sweats as sweating excessively at night in the weeks following childbirth. NHS guidance describes it as waking in the night sweating a lot, and suggests keeping a towel and spare night clothes by the bed so you can get dry quickly.

They are common. Cleveland Clinic notes that some research suggests around 35% of people who have just given birth report night sweats, and its guide to the weeks after delivery says that increased sweating, especially at night, is common as your body adjusts to new hormone levels.

Why do postpartum night sweats happen?

Two things are going on at once. The sources below describe the same causes without separating a normal delivery from a C-section delivery.

• Hormones. Estrogen and progesterone levels fall steeply after you give birth. Those hormone changes affect the hypothalamus, the part of your brain that controls body temperature, and low estrogen makes it believe you are too hot.
• Fluid. Your blood volume increases by about 50% during pregnancy. Cleveland Clinic explains that night sweats could happen because your body is shedding that extra fluid.

When do postpartum night sweats start, peak and stop?

Sources describe them as something that happens in the weeks after childbirth, and at their worst early on. Cleveland Clinic says they tend to be worst in the first two weeks after giving birth, and NHS guidance says the same about the first couple of weeks.

How long they last is where the sources differ, and it is worth being honest about that:

• One Cleveland Clinic overview says the extra sweating should subside within a week or two.
• Its dedicated night sweats page says it takes a few weeks for your hormones to readjust, after which night sweats typically end, and to check with your provider if they last longer than three weeks.
• A Cleveland Clinic article on postpartum sweating says the stage usually passes within about one to two months, give or take a few weeks, and advises seeing your provider if you still have severe night sweats more than a month after birth.
• The NHS says they can last longer than the first couple of weeks, particularly if you are breastfeeding.

A fair reading is that most people notice the sweats easing over the first few weeks. If they are still heavy after about three to four weeks, it is reasonable to mention them to your doctor, even if you feel otherwise well.

Does breastfeeding make night sweats last longer?

It can. Prolactin, the hormone that drives milk production, keeps estrogen levels low. Cleveland Clinic says that if you are lactating you tend to sweat a little more, and that breastfeeding mothers may sweat more, and for longer, than those who formula feed. NHS guidance gives the same picture: the sweats can last longer, particularly if you are breastfeeding. It simply explains why your sweats may outlast a friend's.

Because you are losing fluid through sweat, and making milk too, Cleveland Clinic advises drinking plenty of water, as excessive sweating could lead to dehydration.

How to manage postpartum night sweats

Cleveland Clinic is plain that you cannot prevent them. What you can do is make nights less miserable:

• Wear light night clothes made of cotton or silk.
• Use cotton sheets, which tend to be more breathable and cool.
• Lay a bath towel under your body, and add a second pillowcase to protect your pillow.
• Put a waterproof protector over your mattress, under the sheet.
• Use a fan, open a window or turn the air conditioning down.
• Keep spare night clothes and a towel next to the bed so you can get dry and warm again quickly.
• Change your clothes through the day and night if you need to, and change your sheets regularly.
• Drink plenty of fluids through the day and night.

When sweating is not the normal kind

Normal postpartum night sweats happen on their own. Sweating is more worrying when it comes with other symptoms. Cleveland Clinic says to contact your provider if you have fever, chills or pain along with night sweats, as this could be a sign of an infection. Infections that can follow birth include:

• Endometritis, a bacterial infection in the lining of the womb. Cleveland Clinic describes steady tummy pain, sometimes with fever, chills or feeling generally unwell, and foul-smelling vaginal discharge as signs to report.
• Mastitis. Breasts that are painful, burning, warm to the touch or have red streaks can be a sign of mastitis, and most cases need antibiotics.
• A wound infection after a C-section. Get medical attention for a fever, foul-smelling discharge, or incision pain that gets worse instead of better.

Thyroid problems are another thing to keep in mind if symptoms appear or return later. Postpartum thyroiditis is inflammation of the thyroid gland within the first year after pregnancy; Cleveland Clinic estimates it affects 5% to 10% of women in that year. Its overactive phase usually happens between one and six months after a pregnancy and can cause feeling very sensitive to heat, anxiety, a rapid heart rate, hair fall and unexplained weight loss. Cleveland Clinic notes that many people delay seeing a provider because they assume these changes are a normal part of recovery.

When to call your midwife or doctor

• You have a fever or chills with the sweats. Cleveland Clinic advises calling for a temperature over 100.4°F (38°C) or severe chills after delivery.
• You have pain, such as a sore, tender tummy, a painful red area on your breast, or a C-section wound that is more painful, red or leaking.
• Your vaginal discharge smells foul, or your bleeding gets heavier.
• You feel unwell alongside the night sweats, or they are a big problem or go on for a long time. NHS guidance says to speak to your GP.
• You still have heavy night sweats after about three weeks to a month.
• You have a racing heart, feel very sensitive to heat, or are losing weight without trying in the months after birth.
• You have sudden or very heavy bleeding, feel faint or have a rapid heartbeat. The NHS says to tell your midwife, health visitor or GP straight away; if bleeding is excessive, Cleveland Clinic advises going to the nearest emergency department.

If you are tracking how your nights are going, MatraBloom's daily check-in and week-by-week recovery timeline can help you notice whether the sweats are easing, and give you something concrete to show your provider if they are not.

See what is typical in each week of postpartum recovery

Frequently asked questions

Notice when something changes

MatraBloom's daily check-in takes a minute and gives you a simple record of how you have been feeling, which is easier to share with your midwife or doctor than trying to remember at 3 a.m.

Continue reading