Circulation & Breathing
Fatigue & Tiredness in Pregnancy
Deep tiredness driven by pregnancy hormones and the physical demands of pregnancy — common in the first and third trimesters.
Written and fact-checked by the ParentVibes editorial team against WHO, NHS, ACOG and peer-reviewed guidance. Not yet reviewed by a named clinician.
Quick facts
- When it's worst
- First trimester, then again in the third
- Main cause
- Rising progesterone and extra energy demands
- Usually eases
- Somewhat in the second trimester
- Helps most
- Extra rest, short naps, iron-rich food
- See a doctor if
- Exhaustion is extreme or comes with breathlessness or pallor
It's hard to overstate just how tired pregnancy can make you feel — many people describe first-trimester fatigue as unlike any tiredness they've experienced before, even after a full night's sleep. This isn't in your head or a sign you're not coping; it reflects real, significant changes happening in your body.
Fatigue tends to ease a little once you reach the second trimester, then often creeps back in the third as your bump grows, sleep becomes trickier and your body works harder to support your baby. This guide covers why pregnancy is so tiring, how to protect your energy, and the less common warning signs worth mentioning to your doctor or midwife.
What is pregnancy fatigue?
Pregnancy fatigue is a deep, often overwhelming tiredness that goes well beyond feeling a bit sleepy. In the first trimester it's linked to a sharp rise in progesterone, a hormone with a natural sedating effect, alongside the substantial energy your body spends building the placenta and supporting early development. Many people also find it harder to sleep well because of nausea, frequent trips to the toilet or racing thoughts.
By the second trimester, energy often picks up as hormone levels settle. In the third trimester, tiredness commonly returns — this time driven by the physical load of carrying a larger bump, disrupted sleep, backache and getting up repeatedly overnight to urinate. All of this is a normal, expected part of pregnancy for most people.
It's not just 'being tired'
Pregnancy fatigue reflects real physiological work — increased blood volume, a faster metabolism and building an entirely new organ, the placenta. Be as kind to yourself about rest as you would be about any other demanding physical task.
What causes fatigue in pregnancy?
Several overlapping factors make pregnancy so tiring, especially in the first and third trimesters:
Rising progesterone
This hormone rises steeply in early pregnancy and has a natural sedative effect, which is a major reason first-trimester tiredness can feel so heavy.
Increased blood volume and a faster metabolism
Your body works harder around the clock — your heart pumps more blood and your metabolic rate rises to support your growing baby, which takes energy.
Disrupted sleep
Nausea, needing the toilet more often, heartburn, leg cramps and a growing bump can all interrupt sleep, particularly in the first and third trimesters.
Low iron (anaemia)
Iron demands increase in pregnancy, and if intake doesn't keep pace, iron-deficiency anaemia can leave you feeling especially drained.
Emotional and physical adjustment
Processing the news of pregnancy, appointments, and simply carrying more weight all add to how tired you feel.
Carrying more than one baby
Twin or higher-order pregnancies place greater demands on your body and are often linked with more pronounced fatigue.
Fatigue can feel worse if…
- You're also experiencing morning sickness
- You have a physically demanding job or care for other children
- You're not getting enough iron or other key nutrients
- You're expecting twins or more
When fatigue is normal
Feeling more tired than usual is expected for most of pregnancy. These patterns are reassuring:
- Tiredness that improves with extra rest, a short nap, or an early night.
- Fatigue that's most intense in the first trimester, eases in the second, and returns mildly in the third.
- You can still function day to day, even if you need more downtime than before.
- Tiredness without other worrying symptoms like breathlessness at rest, chest pain or very pale skin.
| Usually normal fatigue | Needs medical attention | |
|---|---|---|
| Severity | Tired but manageable with rest | Overwhelming exhaustion that rest doesn't touch |
| Onset | Gradual, in step with trimester | Sudden and severe |
| Other symptoms | None, or mild low mood | Breathlessness, pale skin, dizziness, fast heartbeat |
| Function | Still able to manage your day with pacing | Struggling to function at all |
Naps count
There's no need to 'push through' pregnancy fatigue. A 20–30 minute nap or an earlier bedtime is a legitimate and effective way to manage it.
Warning signs — get medical help now
Fatigue is rarely an emergency on its own, but occasionally it points to something needing prompt attention. Contact your doctor or midwife urgently if:
Seek urgent medical care if you have
- Sudden, extreme exhaustion that comes on quickly and feels very different from your usual tiredness.
- Fatigue together with breathlessness, a racing heart, or noticeably pale skin, lips or nail beds (possible signs of significant anaemia).
- Fatigue with a severe headache, vision changes, swelling of your face or hands, or pain under your ribs (possible pre-eclampsia).
- You feel faint, dizzy or you actually pass out alongside the tiredness.
- Fatigue with a fever, or that comes with feeling generally unwell.
If you ever notice your baby's movements have slowed down, changed or stopped, contact your maternity unit the same day, whatever else is going on.
Don't dismiss sudden, severe exhaustion
'Everyone's tired in pregnancy' shouldn't stop you getting checked if your tiredness feels different, sudden or extreme — treatable causes like anaemia are common and easy to test for.
Self-care & managing your energy
You can't eliminate pregnancy fatigue, but these habits help you manage it:
Prioritise rest
- Go to bed earlier than usual, even by 30–60 minutes.
- Take short daytime naps (20–30 minutes) where you can.
- Say yes to offers of help and let lower-priority tasks wait.
- Build in rest breaks rather than waiting until you're exhausted.
Support your sleep quality
- Keep a consistent bedtime and wake time where possible.
- Use pillows to support your bump and back for comfort.
- Limit caffeine, especially from the afternoon onwards.
- Wind down with a calm routine before bed.
Eat well and stay active
- Eat iron-rich foods, such as lean meat, beans, leafy greens and fortified cereals.
- Keep meals and snacks regular to avoid energy dips.
- Gentle activity like walking can boost energy more than resting all day.
- Stay well hydrated.
Pace yourself
- Break tasks into smaller chunks with breaks between.
- Delegate where you can, at home and at work.
- Be honest with yourself and others about needing more downtime.
Ask about an iron check
If tiredness feels excessive, ask your midwife about checking your iron levels at your next routine blood test — treating anaemia often makes a noticeable difference.
When to consult a doctor
Book a non-urgent appointment with your doctor or midwife if:
- Fatigue is affecting your ability to work, care for yourself or function day to day.
- You feel persistently exhausted despite resting well.
- You have other symptoms like breathlessness, pale skin or a racing heart alongside tiredness.
- You suspect low mood or anxiety is contributing to how drained you feel.
- You have a health condition, such as a thyroid problem, that could be affecting your energy.
Notice your energy patterns
Tracking your sleep and energy day to day can help you and your midwife spot patterns and decide if further checks are needed.
Open the Pregnancy TrackerFrequently asked questions
Why am I so exhausted in early pregnancy?
Rising progesterone, increased blood volume, a faster metabolism and disrupted sleep all combine to make first-trimester fatigue feel far heavier than ordinary tiredness.
Does pregnancy fatigue ever go away?
For most people it eases in the second trimester as hormone levels settle, then commonly returns to some degree in the third trimester as the physical demands of a growing bump increase.
Can fatigue be a sign of anaemia?
Yes, especially alongside pale skin or breathlessness. Your midwife checks your blood count at routine antenatal appointments, and iron-deficiency anaemia is easily treated once found.
Is it safe to nap during pregnancy?
Yes. Napping is a safe and effective way to manage pregnancy fatigue, and there's no evidence it causes any harm — listen to your body and rest when you need to.
How much rest do I actually need in pregnancy?
There's no fixed amount — it varies from person to person and trimester to trimester. Most people need noticeably more rest than before pregnancy, particularly in the first and third trimesters.
When is tiredness in pregnancy a red flag?
Seek prompt medical advice for sudden, extreme exhaustion, especially alongside breathlessness, pale skin, a racing heart, fainting, or other signs of pre-eclampsia such as a severe headache or swelling.
Your next steps
Track your pregnancy
Log symptoms week by week, get personalised tips, and see how your pregnancy is progressing.
Open Pregnancy TrackerPregnancy week-by-week
Follow your baby's growth and your body's changes from week 1 to 40 in plain language.
Explore the guideFind a gynaecologist
Have a personal concern? Book with a trusted obstetrician or gynaecologist near you.
Find a doctorRelated pregnancy symptoms
Helpful resources
Sources
- NHS — Pregnancy: common symptoms & concerns
- ACOG — Pregnancy resources (American College of Obstetricians and Gynecologists)
- WHO — Maternal health & pregnancy care
- NHS — Tiredness and sleep problems in pregnancy
Next review due: 6 January 2027.
Medical disclaimer
This page is general information about a common pregnancy symptom and does not replace personal medical advice. Every pregnancy is different. If you have severe pain, heavy bleeding, a bad headache with vision changes, reduced or absent baby movements, breathing difficulty, fever, or you feel something is seriously wrong, contact your doctor or midwife or go to your nearest emergency department straight away. When in doubt, always get checked — it is never a waste of anyone's time.
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