Sleep science: sleep better in pregnancy

Sleep scientist Clare Ladyman offers sleeping tips for pregnancy in this extract from her book.

Sleep is an essential part of healthy living and is just as important as eating, drinking and breathing. When we have healthy sleep, we feel, think and function better. This is because sleep gives our bodies time to rest, restore, grow and strengthen. Healthy sleep allows our bodies to maintain a strong immune system, improves creativity and assists in regulating our appetite. It also allows our brains to create and store memories and to complete tasks quickly and accurately.

Importantly, sleep plays a big part in balancing our emotions. Sleep is like a built-in source of resilience; a precious tool to help you manage the demands of a busy life. And now that you’re pregnant – a busy body. Research has also shown that having healthy sleep in pregnancy can have immediate and long-term benefits for you and your baby. That’s why it’s essential to prioritise sleep in pregnancy.

While some women experience little change in their sleep, you may find that the physiological, psychological and hormonal changes that occur in pregnancy make getting enough good quality sleep throughout pregnancy a significant challenge. Or perhaps the sleep difficulties you were experiencing prior to being pregnant have intensified. 

Some sleep issues can last the length of pregnancy, but many sleep challenges depend on the trimester you’re in.  In the first trimester, your body is undergoing enormous change so it’s not uncommon to feel exhausted. Your body experiences an enormous surge in hormones which can contribute to waking more in the night due to frequent trips to the toilet or from feeling nauseous.

HOW PREGNANCY HORMONES AFFECT YOUR SLEEP
Although there are a range of hormones that affect sleep throughout pregnancy, we are going to look at two vital first trimester hormones: progesterone and oestrogen. These are incredibly important for a healthy pregnancy, but unfortunately they have some unwanted side effects on your sleep and energy levels.

PROGESTERONE
The production of progesterone rises rapidly at the beginning of pregnancy, as it’s vital in keeping the placenta functioning properly and the uterus lining thick and healthy. It also plays a key role in keeping the uterus muscles relaxed so it can expand for your growing baby. However, progesterone is a soporific hormone, which means it makes you feel sleepy so it’s only natural that increased progesterone equals increased sleepiness!

Progesterone also increases your body temperature and secretions from your sweat glands, making you feel hot and sweaty, which can disrupt sleep.

Progesterone’s role as a muscle relaxant is important for your expanding uterus, but it also relaxes other muscles and ligaments in your body, such as your digestion muscles. These usually contract to keep your food and gastric acids in your stomach. But when they relax, the contents of your stomach can move up into your throat and mouth, causing heartburn and reflux.

OESTROGEN
This is the heavyweight of the pregnancy hormones and you’ll produce more oestrogen during one pregnancy than you will in the rest of your life. Oestrogen increases blood flow in the placenta and uterus, which allows the transfer of nutrients to your baby and creates a healthy uterine lining.

Oestrogen stimulates your baby’s hormone production, which triggers their organs to develop. The rapid rise of oestrogen is thought to be the main reason why women can feel so nauseous in the first trimester (morning sickness). The severity and frequency of nausea varies enormously, and while it generally lessens in the second trimester, it can sometimes persist throughout pregnancy. Persistent nausea at any stage of your pregnancy can make you feel incredibly tired.

Oestrogen also promotes breast growth as your milk ducts develop, which can make them feel tender. This can make it difficult to find a comfortable sleeping position, or you may find you wake at night. Finally, oestrogen can trigger mucous production, which can affect your sleep by causing nasal congestion when you’re lying down.

SLEEP IN THE SECOND TRIMESTER
The second trimester may bring some welcome relief if you’ve had a difficult first few months. Progesterone and oestrogen levels will stabilise and for many women this means more energy and less sleepiness compared to the first trimester.

However, towards the end of the second trimester, you may find that heartburn, nasal congestion, back, neck and joint pain, Braxton Hicks contractions, leg cramps or restless leg symptoms can start to disrupt your sleep. Your baby’s movements may also start to wake you as they get bigger. The second trimester is also when many women experience vivid dreams – and snoring.

SLEEP ON YOUR SIDE
In the second trimester, from around 28 weeks, it becomes more important to try sleeping on your side. This is because the weight of your baby can restrict the flow of blood in the large vein (called the inferior vena cava) that takes blood back from the lower body to the heart. For your main night sleep and any day naps, going to sleep on your side reduces the risk of stillbirth. But it’s important not to worry if you wake up on your back: it’s natural to change sleeping positions when you sleep. Just roll onto your side and try going back to sleep. It can help to put a pillow behind your back to provide more support and to prevent you from rolling onto your back. Or you could try lying with your legs and knees bent, with a pillow between your knees and a pillow under your stomach.

SLEEP IN THE THIRD TRIMESTER
Getting good-quality sleep in the third trimester can be challenging. Just like the first trimester, your body is going through some huge changes. It has to make room for your baby’s rapid growth, and you will expend a huge amount of energy to keep up with your body’s physical requirements.

Emotionally, the countdown to labour and becoming a new mum can feel quite exciting, but sometimes overwhelming too. Because of all the changes, your sleep can become more restless, and you may be awakened by noises that you would normally sleep through. In the third trimester, almost all women wake up multiple times – three times per night on average – and the awakenings usually last longer. This can leave you exhausted and drowsy during the day, and also affect your memory, concentration and mood.

WORRIES AND ANXIETIES    
Nearly half of all pregnant women worry about their sleep in the first and second trimester or experience insomnia. This can increase to three-quarters of women in the third trimester. Insomnia is regularly having difficulty with sleep, caused by problems falling asleep, staying asleep, waking up too early and/or not feeling refreshed after waking. It’s very common to have a busy mind when you hop into bed. Maybe you’re having anxious thoughts about the health of your baby, the birth, your work, or how you might balance work or finances. You may be feeling excited about meeting your baby, getting baby clothes or thinking of names. Or you might just be thinking about your to-do list. Maintaining gentle, regular exercise routines and using relaxation strategies can be effective ways of helping to calm those busy thoughts. There are a range of mindfulness and relaxation apps available, such as Mind the Bump, Smiling Mind, or Headspace. Insomnia can be a complex problem, so it’s important to talk to your healthcare provider if any of your worries or thoughts are causing you concern. Understanding how sleep works and having realistic expectations about pregnancy sleep can also help.

 
KNOW YOUR 'NORMAL'
The impact of pregnancy on your sleep may sound a bit disheartening. It may seem that a good night’s sleep over the next few months is unattainable.  But remember, not all women will experience poor sleep. Knowing what ‘normal’ sleep looks like in pregnancy helps you form realistic expectations. Pregnancy is an amazing life event and one that brings enormous change. Having the same sleep as before you were pregnant can be difficult – some nights will be great and some nights will be tricky – please know that this is okay. Be gentle on yourself.