Third Trimester Exhaustion

Why the late version is different

Everyone is warned about first-trimester exhaustion. Fewer people are warned that it comes back, and the third-trimester version has different causes and different remedies.

The NHS sets out the late picture: "Later in pregnancy, you may feel tired because of the extra weight you're carrying. Make sure you get plenty of rest. As your bump gets bigger, it can be difficult to get a good night's sleep. You might find that lying down is uncomfortable or that you need to use the loo a lot."

So where the first trimester is hormonal, the third is mechanical and cumulative. You are carrying more weight through every ordinary movement, and you are doing it on interrupted sleep. That combination compounds over weeks in a way that a single early-pregnancy day of exhaustion does not.

The HSE lists the drivers of pregnancy tiredness generally: hormonal changes, physical changes because "pregnancy uses a lot of energy as your body changes", circulatory changes including more blood being produced, blood pressure that may drop and blood sugar that may be lower, and emotional changes.

The tiredness that needs a blood test

One pattern is worth separating out, because it is common in late pregnancy and it is treatable.

The NHS lists the main symptoms of iron deficiency anaemia as:

• tiredness and lack of energy
• shortness of breath
• noticeable heartbeats (heart palpitations)
• paler than usual skin
• headaches

And it names pregnancy directly: "Heavy periods and pregnancy are very common causes of iron deficiency anaemia. In pregnancy, iron deficiency anaemia is most often caused by a lack of iron in your diet."

If your tiredness comes with breathlessness on mild exertion, a heartbeat you can feel, or headaches, that combination is worth raising rather than absorbing. NICE's antenatal care guideline builds routine blood testing into the schedule for exactly this reason, so the test is usually already booked — but symptoms between appointments are worth reporting.

The NHS also lists less common symptoms that are useful clues: food tasting strange, feeling itchy, a sore tongue, hair loss, restless legs syndrome, and wanting to eat non-food items such as paper or ice.

And the tiredness that is mood

The NHS makes this link explicitly: "Occasionally, sleeplessness — when accompanied by other symptoms — can be a sign of depression. If you have any of the other symptoms of depression, such as feeling hopeless and losing interest in the things you used to enjoy, speak to your doctor or midwife."

It adds elsewhere that "being tired and run-down can make you feel low", which runs the other way. Both are worth mentioning, and both are treatable.

Sleep position, and the one rule that matters

The NHS is unambiguous here: "The safest position to go to sleep is on your side, either left or right. Research suggests that, after 28 weeks, falling asleep on your back can double the risk of stillbirth. This may be to do with the flow of blood and oxygen to the baby."

It follows that immediately with the reassurance that stops people lying awake policing themselves: "Do not worry if you wake up on your back, you can turn over and go to sleep again on your side."

Practical suggestions it gives: support your bump with pillows, and put a pillow between your knees.

What helps

The NHS list for late pregnancy sleep and tiredness:

• Make time to sit with your feet up during the day, and accept offers of help.
• Relax before bedtime so you are not wide awake, and ask your midwife about relaxation techniques.
• Avoid napping in the afternoon or evening, since it may mean you are not tired at bedtime.
• Avoid tea, coffee or cola in the evening, because caffeine makes it harder to get to sleep.
• Consider antenatal yoga or pilates, making sure the instructor knows you are pregnant.
• Do some activity even when you feel tired — a walk at lunchtime, or swimming — because exercise can help you feel less tired.
• Eat a healthy diet, and get plenty of rest and sleep.

Two of those are counter-intuitive and worth flagging. Exercising when exhausted usually helps rather than hinders. And napping late in the day is often what is keeping you awake at 11pm, which then gets blamed on the bump.

The strange dreams

The NHS names something that adds to broken sleep and rarely gets mentioned: "You may have strange dreams or nightmares about the baby, and about labour and birth. This is normal." It suggests talking about them with your partner or midwife, and adds a line worth keeping: "just because you dream something, it does not mean it's going to happen."

Managing the expectations rather than the tiredness

The NHS reassures on the important question: "Feeling tired will not harm you or your baby, but it can make life feel more difficult."

The realistic position for the last eight weeks is that some of this is not fixable, only reduced. Broken sleep because you need the loo three times a night, or because you cannot get comfortable, will not be solved by sleep hygiene. What helps is lowering what you expect of yourself during the day, taking the rest you can get in fragments rather than saving it up, and asking for help rather than proving you do not need it.

What is worth acting on rather than accepting: breathlessness, palpitations, headaches, or a mood that has flattened alongside the tiredness. Those are not the bump.