fatigue.
last revised · reviewed 2026-07-05
Profound tiredness is one of the earliest and most universal pregnancy symptoms, driven mainly by rising progesterone and the sheer metabolic work of building a placenta. It is usually worst in the first trimester, lifts in the second, and often returns in the third.
what it feels like
This is not ordinary tiredness — many women describe a heavy, bone-deep exhaustion that arrives mid-afternoon like a wall, or the feeling of having run a race by 7pm. Needing a nap, sleeping ten hours and still waking tired, are all typical in the first trimester.
why it happens
Progesterone, which rises steeply from conception, has a strong sedative effect. At the same time your body is increasing its blood volume, ramping up its metabolism, and building the placenta from scratch — an energy project comparable to sustained exercise. In the third trimester, the physical load of carrying the baby plus broken sleep bring the tiredness back.
what helps
- Sleep when you can — an earlier bedtime achieves more than pushing through
- Short naps (20 to 30 minutes) restore more than they cost; longer ones can leave you groggier
- Gentle daily movement — a short walk paradoxically lifts energy more than resting all day
- Eat regular meals with protein and slow carbohydrates to avoid blood-sugar dips
- Accept help and lower the bar on non-essential tasks — this phase passes
- Keep well hydrated; mild dehydration reads as fatigue
- Ask your midwife about checking your iron if tiredness is extreme — anaemia is common and treatable
when to call your midwife or doctor
- Tiredness with breathlessness, a racing heart, or looking pale — possible anaemia; call your midwife or doctor
- Exhaustion so severe you cannot manage daily activities, or that worsens rather than fluctuates
- Fatigue with excessive thirst and urination — worth ruling out gestational diabetes
- Feeling persistently low, flat, or hopeless alongside the tiredness — tell your midwife or doctor; support is available
This page is general information, not a diagnosis. When in doubt, call — no midwife has ever minded a careful question.
common questions
When does pregnancy fatigue go away?
For most women, first-trimester exhaustion lifts noticeably between weeks 12 and 14, as hormone levels plateau and the placenta takes over. The second trimester is usually the most energetic stretch, before tiredness returns in the final weeks.
Why am I so tired at only 5 or 6 weeks pregnant?
The hormonal changes of early pregnancy are steepest precisely in those first weeks — progesterone alone can rise tenfold. Your body is also building the placenta and expanding blood volume, invisible work that consumes real energy. Feeling wiped out at 5 to 6 weeks is entirely normal.
Is extreme fatigue ever a warning sign?
Usually fatigue is simply part of pregnancy, but if it comes with breathlessness, dizziness, a racing heartbeat, or pale skin, ask your midwife or doctor to check your iron levels — anaemia affects many pregnancies and responds well to treatment.
read it in context
Fatigue tends to show up around these weeks of pregnancy:
related symptoms
- Food aversions
Food aversions — a sudden, visceral repulsion to foods you normally enjoy — affect around 6 in 10 pregnant women, usually starting in the first trimester alongside nausea.
- Sciatica
Sciatica in pregnancy is pain that shoots from the lower back or buttock down the back of one leg, caused by irritation of the sciatic nerve.
- Restless legs syndrome
Restless legs syndrome — a crawling, fidgety urge to move the legs, worst in the evening and at night — affects around 1 in 5 pregnant women, peaking in the third trimester.
know what's normal, week by week
elara tracks your symptoms alongside your weeks.
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