When my son was a baby, he was a terrible sleeper. Even when he was in Elementary school, he was still not a perfect sleeper. I grew to just accept that until he became a teenager when I had to drag him out of bed. My son was sensitive to schedule and routine changes and was, in general, a light sleeper.
I can see this sensitivity in almost every sleep challenge he’s ever had. For example, when my son was 3 years old, he started to have a few night-wakings every night, for 3 nights in a row. I’d expect that behavior occasionally when he was 4 months old. But at 3 years-old, it was very frustrating and probably more tiring for me, since I was no longer used to it.
As you may know, there are lots of reasons that toddlers and preschoolers might wake during the night. As I thought through the possible causes of my son’s night wakings, it occurred to me just how sensitive he is to temperature. And, eureka! I knew I’d found the culprit.
Temperature and Sleep
You see, I realized that the same night he started waking, we had put thermals on underneath his fleece footed PJ’s, because it was so freezing outside and we were worried about him being cold. Instead, because of the clothing change, he was getting too hot those few nights!
Boy, was I happy to figure it out! You’d think he would say, “Mommy, I’m too hot,” but I don’t think he realized why he was waking up.
Unfortunately, he still had a bad night here and there (nightmares, insomnia, etc.), but at least he didn’t get up on most nights and not numerous times EACH night!
So, I did some homework so I could pass on the ideal temperature your baby or toddler’s room should be when he sleeps. Hopefully, my experience again will help others.
Temperature and SIDS
It is very important that you not overheat your newborn when she sleeps as it increases the risk of SIDS. It has also been shown that using a fan can decrease the risk of SIDS by 72%. Also, be sure you don’t use a second-hand mattress.
Body Temperature
Our internal body clock controls our body temperature and when our temperature is high, like during the day, our bodies are more awake. We all have a dip in body temperature in the afternoon and we feel sleepy (Ferber calls this the “afternoon dip”). At night, when the sun goes down, our body temperature starts to drop and Melatonin (a hormone) is released in our bodies inducing sleep. Our temperature is lowest at night until around 4 a.m. our bodies start to prepare to wake up. Many parents complain about their baby’s sleep in the early morning hours. It’s the lightest sleep of the night.
What Temperature to Set Your Thermostat?
The ideal room temperature is between 65 and 70 degrees Fahrenheit (or 18.3 to 21.1 Celsius), but I recommend you use these numbers as a starting point. In my experience of over 10 years, the ideal temperature for your family will vary a little, depending on you (and your baby) and how many blankets you use. Keep in mind that your child won’t learn to keep a cover on all night until over 18-24 months.
With the air conditioning on, 72 degrees can feel cold whereas if you put your thermostat to 72 with the heater, it will probably be too hot. In the summer, at night, we keep our thermostat at 72 degrees Fahrenheit and during the winter we set it to 63 degrees Fahrenheit. Your baby or toddler’s skin should feel cool to the touch, but not frigid like their fingers are ice cubes. And, generally, your child should never be sweating.
For my youngest, we put on a onesie t-shirt, thermal pajamas, and then fleece pajamas over those this winter. For my eldest, we put just Fleece footed pajamas and to go with his sheet and comforter. In the summer, generally, pajamas and a sleep sack (or sheet and comforter) are sufficient.
I didn’t find any scientific research about this (though I’m sure it’s out there), but if our body temperature being higher in the day keeps us awake, I would venture to guess that my son was waking up partially because his body temperature was too high as much as it was because he may or may not have been uncomfortable. The moral of the story is to keep the kids warm, but not too warm, and not too cold, either, yet another parenting magic trick.
My baby wakes up constantly all night. I mean 2-3x in an hour. This is one of the reasons I’m looking into. His room is a dead zone no heat or central air make it so we use a AC in the summer and a heater in the winter.
You mentioned a room feeling cold with a window AC at 72 and I find this is true. The room is freezing! But if I lower it the temp quickly goes back up to 74. I dress him in a onesie and a zippadee zip and although his body is warm his hands and feet are like ice. What do you think?
Hi @Heather – Thanks for writing and so sorry that your baby is waking SO often! The temperature may cause a little relentlessness, but it sounds like you’re doing great at working to regulate the temperature to help with his sleep. Cool hands is good, but perhaps as you mention, 74 degrees will work well for him, if his hands are icy at 72? Comfortable temperatures can vary from person to person and family to family, so do keep playing around with this! You may also want to look at other reasons for his waking, especially since he is waking so often. Have you thought about how he is falling asleep and back to sleep? This article should help:
https://www.babysleepsite.com/sleep-training/sleep-association/
Good luck Heather, and please contact us if you need more assistance at any time!
My wife and I are at odds with temperatures in the summer. She feels that anything above the recommended 72 degrees means our 7 month old is at high risk for SIDS. Specifically up to 80, which the baby’s room (on our 4th floor apartment) reaches some nights. She wants to move because of this. We have a fan in the room and the baby sleeps in a onesie and light sleep sack. In your experience, what do you think?
Hi @Wade – Thanks for writing to us! Sorry to hear that you and your wife are a bit at odds about the temperature for your baby’s room! As parents ourselves, we definitely understand that you both want to keep your baby as safe as possible! It does sound like you’re doing your best at keeping the room cool with a fan and light sleep attire! There are options for cooling fans out there too, as well as portable air conditioners, which would be easier than moving! We can’t decide whether you can/should move or not, but do want to share the best information for safest sleep! There are plenty of places worldwide where babies sleep in warmer temps, but only you and your wife will know what’s best for your family. Your pediatrician may be a great source for local and specific information for you too.
This article on our blog may have some additional helpful information too:
https://www.babysleepsite.com/safety/raising-sids-awareness/
Good luck Pascal!!
What a problem. Our children, parents of our grandchild, insist on no blankets for their 10 month old. When we keep our grandchild we have a terrible problem. My husband and I can not sleep unless the thermostat is set no higher than 68 to 69 at night and that’s with sleeping with nothing on except underwear. The baby is 10 months and too old for a sleep blanket. He gets cold at those temps. I guess we are just going to tell our son we will not keep the grandchild any longer at night. Also, the child is still waking at 4:30 at night and they seem to think there is no problem with that.
Hi @Teresa O Lewis, thanks for writing to us about your grandson. I’m sorry to hear you may need to stop keeping him over night, but the silver lining is it is a time that will pass fairly soon in the grand scheme of things. I don’t know if you’ve tried it, but perhaps you could get the baby some special jammies (like those footed fleece pajamas) to wear just when he’s at grandma and grandpa’s house. I live in Florida so we don’t have a TON of cold nights, but those have been great for my kids on nights it’s cold but we don’t feel it’s necessary to keep the heat on. You could even put a pair of socks on him before putting the pajamas on just to add an extra layer and keep him warmer that way.
In regards to the 4:30 waking, some babies this age do still need to wake 1x a night for a feeding until closer to 12 months, but if he is starting his day at this time that wouldn’t be quite right. If that’s the case, here is a link to an article that may help them out if they’re interested: https://www.babysleepsite.com/how-we-sleep/baby-waking-too-early/
Let us know if you need anything else, we are here to help!