What Are Normal Thyroid Levels for a Woman?

Normal thyroid stimulating hormone, or TSH, levels for women are between 0.4 to 4 milli-international units per liter, according to MedlinePlus. Normal values of TSH can vary in pregnant women.

The normal range of TSH can be different throughout the day, and the measurements can differ depending on the laboratory that tests the blood. Certain medical conditions, such as a pituitary gland disorder, can cause a normal, but low, TSH level, notes MedlinePlus. Controversy about the upper limit of the normal range of TSH levels has led doctors to believe that 3 milli-international units per liter is appropriate, notes About.com. Studies of people without thyroid problems indicate that TSH levels of .4 to 2.5 milli-international units per liter are common.