A high white blood cell count during pregnancy is usually considered normal, as leukocyte and lymphocyte levels in the blood often shift while the body adapts to development of the fetus. These changes reflect typical pregnancy-related immune adjustments.
A complete blood count (CBC) with differential measures the body's defense cells, including leukocytes and lymphocytes. During pregnancy, it helps assess the current status of the immune system.
White blood cell (leukocyte) levels typically return to normal within a few days after delivery. If they remain elevated, a doctor should assess the change alongside the woman's clinical history to rule out underlying disease.
Common causes
A high white blood cell count, also called leukocytosis, commonly occurs during pregnancy. It may be related to stress before labor or the body’s response to the fetus, meaning the body produces more defense cells to help prevent rejection.
White blood cell levels can rise significantly during pregnancy, often exceeding 25.0 K/µL (25,000/µL) of blood. These levels typically decrease gradually after delivery.
Reference values
Reference values for total leukocytes in women aged 14 and older are between 4.5 and 11.0 K/µL. However, during pregnancy these values change as follows:
It is important to remember that reference values vary depending on the person's age and the lab where the test is performed. For this reason, results should always be reviewed with a healthcare provider.
Leukocytes in urine
Leukocytes in the urine can be a sign of a urinary tract infection (UTI), even if there are no symptoms. UTI symptoms include pain or burning during urination and increased urinary frequency.
UTIs are common during pregnancy, particularly between weeks 6 and 24. During prenatal care, your doctor or midwife may therefore request a urine test to diagnose any infection early and start appropriate treatment if needed.