What causes tiredness in pregnancy?

Early pregnancy hormones can make you sleepy while your body adapts. Later, carrying more weight, needing to urinate, discomfort, reflux, leg symptoms, and an active baby can interrupt rest. Emotional changes, work demands, and caring for other children may add to the burden. Anaemia can cause marked fatigue, breathlessness, dizziness, headaches, or a racing heartbeat. An underactive thyroid or vitamin D deficiency may also contribute, particularly when tiredness comes with feeling unusually cold, constipation, muscle weakness, or low mood. Tiredness alone cannot identify its cause.

Rest when possible, keep a regular sleep routine, eat varied meals, drink enough fluids, and use gentle movement if your maternity clinician says it is suitable. Tell your antenatal team if fatigue is persistent or interferes with daily activities. They may review your symptoms and offer blood tests for anaemia or thyroid problems. Do not start iron or vitamin supplements beyond those advised for pregnancy; iron therapy is useful when iron deficiency is confirmed or considered likely, but the dose and timing should be individualised.

Contact your maternity team promptly if exhaustion is sudden, severe, or accompanied by fainting, chest pain, breathlessness at rest, heavy bleeding, fever, severe headache, vision changes, facial or hand swelling, or reduced fetal movement later in pregnancy. These symptoms can have causes that need urgent assessment. Otherwise, mention ongoing fatigue at your next antenatal appointment so treatable contributors are not missed.

Could anaemia, thyroid disease, or another problem explain my fatigue? Do I need blood tests? What rest, activity, and supplement plan is appropriate for my stage of pregnancy?