Cooling Strategies for Pregnant Women to Stay Comfortable in Summer

Summer during pregnancy is considerably more challenging than normal life. Due to hormonal changes, basal body temperature tends to rise, and blood volume increases, making pregnant women more sensitive to heat. As a result, they are at higher risk of heatstroke, swelling, and insomnia, which can also affect their ability to attend NIPT (non-invasive prenatal testing) and regular checkups. In this article, we provide a comprehensive medical guide to cooling strategies for pregnant women to safely get through the summer. We also include product comparisons of helpful cooling goods and tips on how to work with your family for support.

1. Why Pregnant Women Are Sensitive to Summer Heat: Understanding the Mechanism of Thermoregulation

Why are pregnant women particularly vulnerable to summer heat? Medically, several factors contribute to this sensitivity.

• Rise in Basal Body Temperature
  During pregnancy, the secretion of luteal hormone (progesterone) increases, and basal body temperature becomes 0.3 to 0.5°C higher than normal. As a result, when the outside temperature is high, the body’s ability to release heat cannot keep up, making it easier for heat to build up internally.
  
• Increase in Blood Circulation Volume
  During pregnancy, in order to secure blood flow to the fetus, the circulating blood volume increases by about 1.5 times. This additional circulation places more strain on thermoregulation and can also lead to swelling and fatigue.
  
• Changes in Sweating Function
  Due to hormonal influences during pregnancy, the ability to sweat becomes unstable, and there may be times when sweat does not come out sufficiently even when needed. As a result, body temperature tends to be more difficult to lower.
  
• Abdominal Pressure from the Fetus
  The enlarged uterus presses against the diaphragm and blood vessels, which can reduce the efficiency of heat dissipation within the body.
  

➡️ These combined factors contribute to the characteristic that pregnant women are more likely to feel unwell in the summer heat.

2. Cooling Measures Recommended by Obstetricians and Midwives

Among experts, the following lifestyle tips are recommended for pregnant women during the summer.

• Don’t Hesitate to Use Air Conditioning
  Although pregnant women are sensitive to heat, some refrain from using air conditioning out of concern for its effects on the fetus. However, midwives and obstetricians warn that “the risk of heatstroke is far more serious.” It is essential to use air conditioning at an appropriate temperature setting (26 to 28°C).
  
• Sleeping Posture at Bedtime
  The “Sim’s position,” lying on the left side, is effective for improving blood flow in the later stages of pregnancy and is also recommended as a cooling sleeping posture. Using a body pillow helps to distribute body pressure more evenly.
  
• Health Management Before Regular Checkups and NIPT
  It is often advised to schedule prenatal checkups or NIPT in the cooler morning hours and to be sure to stay hydrated before the appointment. It is also important to bring a light jacket or shawl to avoid getting too cold from the air conditioning during the visit.

3.Comparative Review of Cooling Items

We will compare commercially available cooling goods that are especially recommended for pregnant women.

3-1. Cooling Bedding

✅ Contact-Cooling Mattress Pads

• Recommendation Level：★★★★☆
  
• Examples of Manufacturers: Nitori “N-Cool” series, MUJI “Cool Feeling Mattress Pad”
  
• Key Points: The cool sensation is temporary, but the products are reasonably priced and easy to introduce. When used together with a fan, the effect lasts longer.
  
• Recommended for Pregnant Women: Particularly effective for falling asleep on hot summer nights.

✅ ジェルパッド

• Recommendation Level：★★★☆☆
  
• Examples of Manufacturers: Iris Ohyama “Cool Gel Mat”, Yamazen “Gel Cool Pad”
  
• Key Points: Provides sustained cooling, but pressure from the body can cause uneven distribution, which may strain the lower back or back.
  
• Recommended for Pregnant Women: Better used on specific areas such as feet or pillows rather than the entire body.
  

Air Conditioner-Compatible Mattress Pads

• Recommendation Level：★★★★★
  
• Examples of Manufacturers: Panasonic “Air Conditioner-Compatible Mat”, KOIZUMI “Comfort Sleep Mat”
  
• Key Points: Highly breathable, releasing heat and moisture for comfort. Allows comfortable sleep even with lower air conditioner settings.
  
• Recommended for Pregnant Women: Ideal for those in the later stages of pregnancy who want to sleep comfortably for extended hours with a large belly.

3-2. Portable Cooling Goods

✅ Neck Cooler

• Recommendation Level：★★★★★
  
• Examples of Manufacturers: Sony “REON POCKET”, Thanko “Neck Cooler Neo”
  
• Key Points: Cools the carotid artery in the neck, efficiently lowering body temperature. Useful for outings and checkups.
  
• Recommended for Pregnant Women: A strong ally for outings under the scorching sun. Lightweight models are preferable to reduce burden on the neck.

✅ Handy Fan

• Recommendation Level：★★★★☆
  
• Examples of Manufacturers: Francfranc “Fle Handy Fan”, Doshisha “Portable Fan”
  
• Key Points: USB rechargeable and easy to carry. Adjustable wind settings make it convenient to use.
  
• Recommended for Pregnant Women: Useful while waiting for checkups or during hospital visits.
  

✅ Cooling Spray

• Recommendation Level：★★★☆☆
  
• Examples of Manufacturers: Shiseido “Sea Breeze”, Gatsby “Body Paper & Spray”
  
• Key Points: Acts quickly, but some types may be harsh on the skin. Products for sensitive skin are recommended.
  
• Recommended for Pregnant Women: Ideal for cooling clothing before going out. Avoid direct spray on the skin for safety.
  

3-3. Smart Devices

✅ Wearable Thermometer

• Recommendation Level：★★★★★
  
• Examples of Manufacturers: Omron “Wearable Thermometer”, Apple Watch (with heart rate and body temperature functions)
  
• Key Points: Constant monitoring of body temperature and heart rate. Useful for early detection of changes in physical condition.
  
• Recommended for Pregnant Women: Effective for managing health before NIPT or checkups. Helps catch early signs of dizziness or dehydration.

✅ Sleep Management Apps

• Recommendation Level：★★★★☆
  
• Examples of Manufacturers: Fitbit app, Sleep Cycle, Oura Ring app
  
• Key Points: Analyzes sleep quality and assists in adjusting air conditioning and bedding.
  
• Recommended for Pregnant Women: Effective for coping with sleepless nights. Supports creating an environment conducive to restful sleep.
  

🏆 Overall Recommendations

• Prioritize comfortable sleep at home → Air conditioner-compatible mattress pad + sleep management app
  
• Prioritize heat measures while out → Neck cooler + handy fan
  
• Prioritize health management → Wearable thermometer + cooling bedding

4. Ways to Cool the Body from the Inside Through Diet

✅ Tips for Staying Hydrated

• Barley tea:Caffeine-free and contains minerals. Drinking it at room temperature rather than too cold is gentler on the stomach.
  → Example: Add lemon slices to barley tea for a refreshing flavor.
  
• Oral rehydration solution (ORS):Recommended on days with heavy sweating or after checkups and outings. Effective in preventing dehydration.
  
• Lemon water:Adding lemon juice to water provides vitamin C. Easy to drink even when you have no appetite due to summer fatigue.

👉 Example of how to drink throughout the day:

• Morning: One cup of room temperature barley tea
  
• Late Morning: Lemon water (without ice)
  
• Afternoon: ORS with lunch (not overly chilled)
  
• Night: A small amount of room temperature water before bed
  

✅ Use of Foods That Help Prevent Swelling

Vegetables and fruits rich in potassium are effective in reducing swelling during pregnancy.

• Watermelon:Over 90% water and has diuretic properties.
  → Tip: Sprinkle a bit of salt on cut watermelon to help prevent heatstroke.
  
• Cucumber:High in potassium; great in salads or light pickles.
  → Example: Mix cucumber with wakame seaweed and vinegar for added minerals.
  
• Winter melon:Gently cools the body and helps improve swelling.
  → Example: Simmered winter melon with minced meat sauce is easy to digest and ideal for pregnant women.

✅ Desserts: Be Cautious About Overcooling

• Ice cream and shaved ice should be limited to once per day and in small amounts for safety.
  
• Alternatives:
  Yogurt with fruit (e.g., banana + kiwi + yogurt)
  Frozen fruits (e.g., frozen blueberries or mangoes can be eaten as-is)
  → Provide both nutrition and a cooling effect
  

✅ Iron and Folic Acid Intake in Summer

Iron and folic acid are essential for pregnant women, but during summer when appetite decreases, they can be made easier to consume with some adjustments.

• Liver dishes:Instead of stir-frying (which can feel heavy in hot weather), turn it into a liver pâté-style spread on bread for easier consumption.
  
• Spinach:Use frozen spinach to make boiled dishes or sesame dressing salad.
  
• Edamame:Salt-boiled edamame is a great iron-rich snack for summer. Still nutritious even when chilled.
  
• Natto + egg yolk + okra:A sticky rice bowl rich in folic acid and iron. Easy to eat even on hot days.
  

🌸Example of a Daily Meal Plan for Pregnant Women (Summer)

• Breakfast:Barley tea + Yogurt with banana + Whole grain bread
  
• Lunch:Cold udon noodles + Edamame + Simmered winter melon
  
• Snack:Frozen blueberries + Unsweetened yogurt
  
• Dinner:Rice + Steamed chicken breast + Spinach with sesame dressing + Cucumber and wakame in vinegar
  
• Before Bed:Room temperature water + A small portion of watermelon
  

5. Practical Precautions When Going Out

✅ Choosing the Right Time of Day

• Morning (until around 10 a.m.) or evening (after 5 p.m.) is ideal.
  From noon to 3 p.m., both sunlight and temperature reach their peak, significantly increasing the risk of heatstroke for pregnant women and should therefore be avoided.
  
• If going out is necessary, try to shorten the time spent at the destination and split travel time into smaller segments.
  
• For checkups and NIPT appointments, scheduling them for early in the morning, if possible, can reduce the physical burden.
  

✅ Clothing Tips

• Maternity dresses made of UV-protection fabric
  → Breathable and non-restrictive around the belly. Materials like cotton and linen are comfortable and less sticky even when sweating.
  
• Light cardigan
  → Indoor places often have strong air conditioning. A light layer helps you adjust to temperature differences.
  
• Hat & sun umbrella
  → A breathable straw hat is recommended. Choose a sun umbrella with heat and UV protection.
  
• Shoes
  → Sandals carry a risk of falling. Sneakers or flat shoes with heel support are safer options.
  

✅ Planning Your Movement

• Check for shaded routes in advance: Prioritize paths with building shade or covered arcades.
  
• Use public transportation: Avoid walking long distances. Combine bus or train rides with walking.
  
• Rest breaks: Take breaks in cool places every 15–20 minutes. Especially in late pregnancy, sitting down frequently is important.
  
• Essential Items
  • Plastic bottle (room temperature or chilled barley tea in an insulated bottle)
  • Handy fan
  • Cooling towel or cooling spray
    

✅ Emergency Response

Pregnant women have more difficulty regulating body temperature than usual, so heatstroke may progress quickly. Be alert to the signs.

• Warning signs:
  • Severe dizziness
  • Nausea or headache
  • Excessive sweating or absence of sweating
  • Shortness of breath
  • Abdominal tightening or decreased fetal movement
    
• Initial response:
  • Move to a shaded or indoor area and lie down
  • Loosen clothing and cool the body (especially neck, armpits, and groin)
  • Rehydrate little by little (ORS is ideal)
    
• When to contact a medical facility:
  • Blurred consciousness
  • Inability to take fluids due to nausea
  • Severe abdominal pain or bleeding
  • Noticeably reduced fetal movement
    

➡️ Do not hesitate to call 119 (emergency) or contact your obstetrician immediately.

✅ Example of a “Peace-of-Mind Kit” for Pregnant Women When Going Out

• Insulated bottle (with barley tea or lemon water)
  
• Handy fan or neck cooler
  
• UV-protection sun umbrella & hat
  
• Light cardigan for layering
  
• Powdered or jelly-type oral rehydration solution (for emergencies)
  
• Maternal and child health handbook & health insurance card (must-carry for emergencies)
  

👉 By preparing these items in advance, even if you suddenly feel unwell while out, you can respond calmly without panic.

Recommended Places Where Pregnant Women Can Safely Spend Time in Summer

✅ Places to Stay Cool and Safe

• Shopping malls and department stores
  They are well air-conditioned, offer many rest areas, and have well-equipped restrooms. You can also combine walking with shopping.
  
• Libraries and cafés
  Quiet and cool, these places are ideal for reading and relaxation.
  
• Aquariums and museums
  Indoor venues with controlled temperatures where you can walk at your own pace.
  

✅ Places Helpful for Maintaining Health

• Obstetrics and midwifery clinics (for checkups and consultations)
  Because it’s easy to feel unwell during summer, it’s a good idea to have consultations or checkups such as NIPT when you’re feeling uncertain about your health.
  
• Maternity yoga and swimming facilities
  Water-based exercise helps cool the body while improving blood circulation, which also helps prevent swelling.
  

✅ Places for a Quick Refreshment

• Local parks (in the morning or evening)
  Light walks are fine during cooler hours with tree shade.
  
• The homes of friends or family
  Spending time in a cool environment with someone you trust is a good way to refresh yourself.
  

Places Best Avoided

• Outdoor amusement facilities under strong sunlight (e.g., amusement parks, outdoor pools, summer festivals)
  
• Crowded events (high risk of infection and heat)
  
• Long-distance travel that requires extended movement (risk of fatigue and dehydration)

6. Chapter 6: Tips for Summer Prenatal and NIPT Appointments (Outfit Coordination Examples)

✅Basic Considerations

• Clothing that allows easy access to arms and abdomen for blood draws and ultrasound exams
  
• Preparation for temperature differences inside and outside the clinic by bringing a light outer layer
  
• Clothes that do not constrict the body, such as those with elastic waistbands or maternity designs
  
• Breathable and moisture-absorbing materials like cotton or linen are ideal

👗Outfit Coordination Examples

① Maternity Dress Style for Smooth Checkups

• Dress: Front-opening type (convenient for abdominal exams and ultrasounds)
  
• Outerwear: Long linen cardigan (for air conditioning protection)
  
• Footwear: Sneakers or flat shoes (non-slip and safe)
  
• Accessories: Maternity health record book case + 500 ml bottle (for hydration)

👉 Point: Since blood draw is the main procedure for NIPT, a short-sleeved dress with a front opening and a light outer layer is most recommended.

② Comfortable Maternity Pants Style

• Top: Cotton tunic (longer length to cover the belly)
  
• Bottom: Maternity pants with adjustable waistband (loose-fitting silhouette)
  
• Outerwear: Thin UV-cut hoodie (for sun protection and air conditioning)
  
• Footwear: Lightweight slip-ons
  

👉 Point: Ideal for those who walk or use public transportation often. Prioritizes ease of movement and temperature control.

③ Layered Style for Cold-Sensitive Pregnant Women, Even in Summer

• Top: Sleeveless or short-sleeved maternity top
  
• Outerwear: Gauze cardigan (breathable and prevents excessive cooling)
  
• Bottom: Maternity leggings layered with a dress
  
• Footwear: Socks + flat shoes
  

👉 Point: Recommended for clinics with strong air conditioning. Socks are essential for addressing leg chills and swelling.

7. Case Studies — Learning from Real Experiences of Pregnant Women

📌 Case 1: Heatstroke Experience in Late Pregnancy

• Background
  A woman at 35 weeks of pregnancy went out past noon for shopping. The temperature exceeded 33°C. She did not carry a parasol or any cold drinks.
  
• Onset of Symptoms
  While walking, she suddenly experienced “severe dizziness” and “nausea,” and started sweating profusely. Bystanders supported her, and she was taken to the hospital by ambulance. She was diagnosed with mild to moderate heatstroke. Fortunately, there was no impact on the baby, but she needed to rest for several days.
  
• Response and Recovery
  She received an IV drip to replenish fluids and electrolytes. Her condition improved the following day. The doctor advised her that “pregnant women have difficulty regulating body temperature, so heatstroke can progress quickly.”
  
• Lessons Learned
  • Limit outings to mornings or evenings only
  • Always carry cooling sprays and oral rehydration solutions
  • Avoid long walks under direct sun; a parasol or hat is essential

📌 Case 2: Sleeplessness Due to Hot Nights

• Background
  A woman at 22 weeks of pregnancy turned off the air conditioner at night due to concern over excessive cooling. As a result, she experienced hot, sleepless nights and persistent lack of sleep.
  
• Onset of Symptoms
  She suffered from continuous insomnia, resulting in severe fatigue and loss of concentration during the day. Her poor physical condition made it hard to do housework and caused emotional distress.
  
• Response and Recovery
  After consulting a midwife, she was advised to use a cooling mattress pad plus a fan for air circulation. She also adjusted the bedroom temperature to around 27°C and avoided direct cooling.
  Within a few days, her sleep quality improved and daytime fatigue eased.
  
• Lessons Learned
  • Don’t hesitate to use air conditioning; adjust temperature and airflow for safety
  • Improve bedding (cooling pads, body pillows) for better sleep
  • Don’t ignore sleep issues—consult a midwife or doctor for early solutions

📌 Case 3: Feeling Unwell on the Day of NIPT Test

• Background
  At 12 weeks pregnant, a woman had scheduled a NIPT test. Despite feeling unwell from the previous day’s heatwave, she went to the hospital for her 11 a.m. appointment.
  
• Onset of Symptoms
  While heading to the clinic, she experienced severe fatigue and headache. Before the blood draw, she became dizzy and had to sit down. The test was postponed.
  
• Response and Recovery
  The doctor instructed her that “for summer tests, it’s important to schedule them earlier in the day and stay well hydrated.” She rescheduled for 9 a.m. and made sure to drink fluids regularly, completing the test without any issues.
  
• Lessons Learned
  • Prioritize physical condition on test days and avoid overexertion
  • Morning appointments are ideal
  • Stay hydrated and eat a light meal to stabilize blood sugar and energy

8. Enjoying a Comfortable Summer Together — The Husband’s Role

✅Support for Outings and Shopping

• Carrying heavy bags is the husband’s responsibility
  Pregnant women are at risk of heatstroke and falling. When going shopping together, the husband should carry the heavy bags.
  
• Research the travel route in advance
  Before going out, check for “routes with plenty of shade” and “cafés where you can rest,” and guide accordingly.
  
• Provide rides
  Avoid letting the pregnant partner walk under the blazing summer sun. Just picking her up and dropping her off by car can significantly reduce the physical burden.
  

✅ Sharing Household Chores

• Cooking
  The kitchen gets especially hot in summer. The husband can help by cooking dinner, using the microwave, or preparing simple meals.
  
• Cleaning and laundry
  It can be dangerous for pregnant women to hang heavy laundry. The husband should take charge of balcony or outdoor drying.
  
• Use of delivery and support services
  The husband should proactively arrange for grocery delivery or housework support services, so the pregnant partner can rest without feeling guilty.

✅ Mental and Emotional Support

• Make it a habit to ask “Are you okay?”
  Pregnant women can become easily irritated in the heat. A gentle check-in brings a sense of reassurance.
  
• Be a good listener
  Listening to worries and complaints without judgment provides great emotional support.
  
• Refresh together
  Invite her to a cool café or movie theater for a change of pace. This can be an effective way to lift her spirits.
  

✅ Support for Checkups and NIPT Tests

• Accompaniment
  Attending emotionally challenging appointments like NIPT together helps ease anxiety.
  
• Provide transportation
  Since her condition may change after the appointment, it’s important to accompany her home safely by car or public transportation.
  
• Listen to explanations together
  By hearing the doctor’s explanations as a couple, it becomes easier to share and understand important medical information.

Conclusion

Spending summer during pregnancy can be described as “heat protection equals safety management.” Due to the rise in basal body temperature and changes in blood circulation, pregnant women face increased risks of heatstroke, insomnia, and general health decline. However, by adjusting clothing, diet, and living environment, using cooling products, and receiving family support, it is possible to spend this period comfortably.

Furthermore, pregnant women who are scheduled for NIPT or regular checkups can better manage their physical condition by making thoughtful choices about appointment times and how they attend.

To ensure a safe and comfortable summer during pregnancy, we encourage you to try the strategies introduced in this article.