In an ironic twist that’s far from funny, just when you’re at your most exhausted, you Can’t. Freaking. Sleep. Being pregnant is a merciless energy-sapper, and you really do need all the rest you can scrape together–but the universe, unmoved, continues to conspire against your slumber. Here’s the biology behind your sleepless nights.
In the first trimester, the ‘pregnancy hormone’ progesterone spikes. The hormone slows down certain metabolic processes to make way for rapid foetal development, and this creates a sense of fatigue. As the baby grows, the body also has to work harder to support the placenta, which nourishes the foetus. Increased heart rate and blood supply, as well as weight gain and fluid accumulation all put a strain on the body, tiring it out.
And of course, the emotional push-and-pull that comes with expecting is exhausting in itself.
But when you finally hit the sack, things are not so simple.
All the hard work the body is doing means an elevated core temp; night sweats are common, and can keep you tossing and turning.
If you’ve never snored before (or never known about it), you’re likely to start. Rhinitis is the inflammation of nasal passages during pregnancy, and congestion leads to chronic nocturnal cacophony, the likes of which can often wake you from sleep.
In the second trimester, leg cramping is a possibility; the chances of developing disruptive restless legs syndrome is higher if you’ve got low iron levels–which is typical in pregnancy.
Heartburn is another pain–slowed down digestion and a compressed stomach means acid lingers and is pushed up the oesophagus. Lying down only exacerbates the burn.
Hormone surges and anxieties can also concoct crazy dreams–some of the ridiculous subject matter alarming enough to wrest you from zzz’s.
In the third trimester, a burgeoning belly and an active night owl baby makes it virtually impossible to get comfortable enough for sleep.
This is all par for the pregnancy course, but it’s important to pack in the sleep whenever you can–researchers have found that sleep deficiency during pregnancy can have effects that go beyond the usual crabbiness and mind fog that goes with a rough night; one study discovered mums-to-be who got less than 6 hours of sleep per night were 4.5 times more likely to undergo a C-section, with an average 10 hours longer labour than those who slept 7 hours or more. The study also found that women whose sleep had been severely disrupted were even more likely (5.2 times) to have a C-section. It also showed that fatigue and labour outcomes were unrelated.
The conclusion? Eating dinner early and using pregnancy pillows can help alleviate some of the discomfort that messes with sleep, but the fact is you’re not going to sleep like you used to. Nap whenever you can to counterbalance the nighttime sleep disturbances. And turn in early.
“A woman really needs to go to bed earlier when she is pregnant,” emphasises Kathy Lee, professor of nursing at the University of California, who has studied the effects of limited sleep in pregnancy. “Women need the extra rest, and they can’t keep going on the same amount of sleep they got before becoming pregnant.”