Night Sweats During Pregnancy: Causes, Treatment, & More

By Dr. Kenosha Gleaton, OBGYN

There are a lot of bodily changes that occur during pregnancy, like changing hormone levels, increased blood volume, water retention, and more. [1] Many of these changes can lead to a slight increase in body temperature, but is it also normal to experience night sweats during pregnancy? [2-3] 

Night sweats are defined as repeated episodes of heavy perspiration (sweat) during sleep that are heavy enough to soak through clothes or bedding. [4] Night sweats can be very uncomfortable and difficult to manage, and may point to an underlying condition or illness. [4] So, let’s take a look at what the research has to say about night sweats and pregnancy. 

Are Night Sweats Normal During Pregnancy?

As already mentioned, it’s normal for pregnancy to cause a slight increase in body temperature and perspiration. There are many physiological changes occurring during pregnancy that can impact the body’s ability to regulate temperature (thermoregulation). [1] So if you’re experiencing hot flashes from time to time, you’re not alone. In fact, one study found that about 35% of pregnant people report experiencing hot flashes. [3] However, if you’re consistently experiencing night sweats, you should speak with your healthcare provider. High body temperature can lead to health complications for yourself and your baby, so finding ways to manage or prevent regular night sweats is important. [5]  Learn about the danger signs of pregnancy → 

Causes of Night Sweats During Pregnancy

Pregnancy leads to many complex bodily changes. In order to grow and sustain an embryo, you will experience intense hormonal changes, an increase in blood flow, the growth of a new organ, and much more. [1] Many of these changes can lead to hot flashes or night sweats. 

Hormone Levels

Many different hormones play an important role in reproductive health and pregnancy, including estrogen, progesterone, human chorionic gonadotropin (hCG), and others. [1] Research shows that some hormones, like progesterone, can raise your body temperature, potentially leading to hot flashes. [6] Additionally, the body uses estrogen to lower your body temperature by increasing perspiration. [6] This means that your changing hormones may be the reason for your night sweats.  Check your hormones with the women’s fertility test >> 

Blood Flow

Studies show that during pregnancy, blood volume increases by nearly 50%. [7] Our blood is extremely important for transporting oxygen and nutrients around the body as well as to a fetus during pregnancy. This increased blood volume also means an increase in blood supply to the skin, which can make you feel warm and sweat more. [2] 

Medication Side Effects

Some medications, including antidepressants, diabetes medications, steroids, acetaminophen, and high blood pressure medication could be causing night sweats. [8] Speak with your provider about what medications or supplements you’re taking. Support your pregnancy with prenatal vitamins for women

Infection

In some cases, night sweats could be a symptom of an infection. Some illnesses that can lead to night sweats include the common cold, the flu, COVID-19, tuberculosis, some sexually transmitted infections (STIs), and others. [8] If you are experiencing any other symptoms or want to be tested for any infections, speak with your healthcare provider. 

Underlying Conditions

Not only can some bacterial or viral infections lead to night sweats, but some underlying health conditions can also cause increased perspiration or hot flashes. Some examples include an overactive thyroid, endocrine tumors, diabetes, certain cancers, sleep apnea, gastroesophageal reflux disease (GERD), and others. [8] 

 While it can be unsettling to read about the what-ifs, don’t let this list scare you! If you do have an infection or underlying condition, you will likely notice other symptoms. Chances are, your night sweats are a result of normal physiological changes brought about by pregnancy.  Remember to always consult your provider if you have any concerns or questions about your health. 

What Week Do Night Sweats Start in Pregnancy?

So when can you expect to notice a difference in your body temperature? There is no telling if or when someone will have noticeable hot flashes or night sweats during pregnancy, but these symptoms are most commonly seen during the first trimester (weeks 1 to 14) and the third trimester (weeks 27 to childbirth). [8] Read about the early signs of pregnancy. 

How to Relieve Night Sweats During Pregnancy

Night sweats can make it difficult to get a comfortable, restful night's sleep. Fortunately, there are some tips you can try to relieve night sweats during pregnancy [8]: 

• Lightweight clothing: Opt for loose-fitting and lightweight pajamas, such as cotton or linen.
• Comfortable bedding: Use lightweight bedding that can easily be layered, so you can stay comfortable throughout the night. 
• Cooling products: Some products, such as pillows, mattress covers, and more, are made with cooling gels. These can be a great addition to your nighttime routine to keep you cool and comfortable. 
• Control your environment: This may seem like a given, but keep a fan on by your bed, or turn your thermostat down a few degrees at night. It may also be helpful to have an ice pack or cool cloth nearby, in case you need to cool down in the middle of the night. 
• Stay hydrated: Sweating requires a lot of water, and adequate hydration is a requirement for thermoregulation. [9] Be sure to drink a lot of water throughout the day, and rehydrate with pregnancy-safe electrolyte packs from time to time. Sipping on cool water in bed may also help you stay cool, but be careful about drinking too much water before bed.For added hydration and mineral balance, consider incorporating a powdered magnesium drink into your routine.
• Avoid triggers: Some things can make your night sweats worse. Some common triggers include spicy foods, caffeine, hot drinks, tight clothing, and exercising soon before bed. 

Discover Pregnancy Essentials from Natalist

Taking care of your health before, during, and after pregnancy is necessary for promoting healthy outcomes, supporting your baby’s health, and healing post-birth. At Natalist, we’re on a mission to provide you with the products and information you need to support your path to parenthood. Find pregnancy test strips, morning sickness tea, hydration packets, self-care products, and more, or continue reading about pregnancy on the Natalist blog.

References:

1. Gangakhedkar GR, Kulkarni AP. Physiological Changes in Pregnancy. Indian J Crit Care Med. 2021;25(Suppl 3):S189-S192. doi:10.5005/jp-journals-10071-24039
2. Common health problems in pregnancy. National Health Service. March 2021. https://www.nhs.uk/pregnancy/related-conditions/common-symptoms/common-health-problems/
3. Thurston RC, Luther JF, Wisniewski SR, Eng H, Wisner KL. Prospective evaluation of nighttime hot flashes during pregnancy and postpartum. Fertil Steril. 2013;100(6):1667-1672. doi:10.1016/j.fertnstert.2013.08.020
4. Night sweats. Mayo Clinic. January 2024. https://www.mayoclinic.org/symptoms/night-sweats/basics/definition/sym-20050768
5. Samuels L, Nakstad B, Roos N, et al. Physiological mechanisms of the impact of heat during pregnancy and the clinical implications: review of the evidence from an expert group meeting. Int J Biometeorol. 2022;66(8):1505-1513. doi:10.1007/s00484-022-02301-6
6. Charkoudian N, Stachenfeld N. Sex hormone effects on autonomic mechanisms of thermoregulation in humans. Auton Neurosci. 2016;196:75-80. doi:10.1016/j.autneu.2015.11.004
7. Soma-Pillay P, Nelson-Piercy C, Tolppanen H, Mebazaa A. Physiological changes in pregnancy. Cardiovasc J Afr. 2016;27(2):89-94. doi:10.5830/CVJA-2016-021
8. Night Sweats. Cleveland Clinic. September 2022. https://my.clevelandclinic.org/health/symptoms/16562-night-sweats
9. Popkin BM, D'Anci KE, Rosenberg IH. Water, hydration, and health. Nutr Rev. 2010;68(8):439-458. doi:10.1111/j.1753-4887.2010.00304.x

Dr. Kenosha Gleaton is board-certified in gynecology and obstetrics and is the Medical Advisor of Natalist. She received her MD from MUSC and completed her residency at Carolinas Medical Center in Charlotte, NC.