- Keep baby at home for at least its first 40 days and 40 nights
- Once babe is over 5-weeks old and over 5-kilos weight – then they are robust enough to face the world
So a newborn with no hat on and very little hair to keep their head warm, is equivalent to you and I being undressed to our nipple-line and our heads shaved! Brrrrrrrr. Put a woolen (not nylon) hat on your baby – thin in summer, thicker in winter.
In young babies, signs of hypothermia (low body temperature) include rosy cheeks and lethargy, which can easily be mistaken as a bonny contented sleepy baby. But in reality what is actually happening, is that their metabolism has escalated requiring increased oxygen and glucose to step-up their heat production. Cold-stress is actually the most common thermal hazard facing newborn babies.
The best way for babies to avoid convection heat loss, is being in what is termed a “thermally neutral environment” – that is a nursery/household temperature of 25°C-27°C. This is especially essential when transferring a newborn from birth-delivery to post-natal care facilities (or home) within 24 hours of birth – as full-term newborns are rarely able to shiver (to warm their bodies up), which makes them extremely vulnerable to heat-loss, even from simply breathing in cool air. So if your baby needs to leave the warmth of a hospital maternity ward, then do pre-warm the car’s interior before putting Bubs into it to drive anywhere!
At home, fan heaters tend to produce ‘dry’ air, and gas heaters tend to produce ‘wet’ air. So my personal favourite heaters for maintaining an ambient newborn environment are the electric oil-filled heaters or heatpump with their automatic thermostatic temperature controls. They can produce and maintain lovely warmth – ideally a large heater for the lounge-dining, and a little one for each bedroom.
Air temperature is especially important when a baby is wet (eg being bathed) because they are then also vulnerable to rapid heat loss through evaporation of water from the skin (remembering that as a naked fetus in their mother’s womb, they were used to being in a water temperature of around 37.5°C – like a warm spa-pool). So a good rule of thumb at baby bath time, is a bath water temperature of about 36.7°C; using pre-warmed towels; always drying Bub’s head first; and then after drying their body replacing the wet towels with dry towels.
Babies are also vulnerable to heat loss through radiation, that is being near cold objects such as windows and draughts; and conduction, that is being in contact with cold objects such as a cold mattress. As a rough guide, if the environment feels warm and uncomfortable to an adult dressed in thin clothes with short sleeves, then it is probably a perfect temperature for a newborn, with a thin hat and light cardy on!
When it comes to going out to the shops or for a stroll in the pram after 5-6 weeks of age, then on a cool day an infant generally requires at least a singlet, long-sleeved stretch’n’grow, booties, cardy and hat (ensuring the nape of their neck is also kept warm). On a cold day, Bubs typically needs a thermal singlet, long-sleeved stretch’n’grow, booties, jacket, hat, mittens and shawl or cocoon-wrap. And on a windy day – well heck, Bubs needs to stay at home!
If the pram is forward-facing, as most modern prams are, then a windbreak pram-cover is also strongly recommended. The backward-facing prams (when Mum and Bubs can look at each other) can be gentler on young babies, though less interesting for toddlers – some prams have reversible handles, so provide the best of both worlds. Another ‘must’ in the pram in winter, is a buggy-liner comfort-insert or sleeping-bag cocoon.
Once a baby is crawling, then they will be producing body heat through their muscular activity. So if they’re busy crawling around the house, they would be pretty much fine in the same number of clothing layers as adults. But until then, they generally need at least one extra layer.
And even when out and about if your munchkin is sitting non-mobile in a pram, then crawlers still need at least one extra layer than the adult who is making body-heat from walking pushing the pram. And if it is completely unavoidable to venture out on a windy day, then do ensure Bub’s hat also covers their ears!
The same ‘rules’ apply with bedtime arrangements. Ensure the cot is draught free; lightly pre-warm the cot mattress with a wheatie-bag or similar; ensure the room’s air temperature is thermally-neutral (25°C-27°C) and that it will stay that way overnight (that’s where the thermostatically controlled oil-filled or wall heaters can be marvelous); and use 1-2 more bedding layers than you would need yourself. That is, if you would sleep with pajamas, sheet and two blankets – then Bubs will need a singlet, pajamas, sheet and 2-3 blanket layers. After the newborn phase, sleep-bags, particularly my BabyOK Babe-Sleeper which is attached to its own base-sheet, can be ideal replacements to a sheet and/or blanket.
At the other end of the spectrum, it is equally as important not to overheat babies, for they are also poorly equipped to cope with Hyperthermia (high body temperature) such as being in a hot vehicle. The normal adult hyperthermic response (reducing a high core temperature) is removing some clothing, and sweating – but babies can do neither.
The big reality is that young babies naturally tolerate a very limited range of environmental temperatures – so as parents we all do need to be vigilantly observant of our baby’s temperature. If you’re ever unsure, then check their temperature. In young babies especially, ideally you want to aim for high 36s or low 37s Celsius (98-99 Fahrenheit).
Kathy Fray is a New Zealand writer and midwife, author of the best-selling “OH BABY…Birth, Babies & Motherhood Uncensored”, and internationally popular “OH GROW UP…Toddlers to PreTeens Decoded”, and body-mind-spirit manuscript award-winning “OH GOD – WHAT THE HELL DO I TELL THEM?! Guide for vaguely spiritual Parents”.