Final answer:
The nurse should report a Thyroid-stimulating hormone (TSH) level of 4.5 mIU/L to the provider.
Step-by-step explanation:
A nurse should report a Thyroid-stimulating hormone (TSH) level of 4.5 mIU/L to the provider. TSH is a hormone produced by the pituitary gland that stimulates the thyroid gland to produce thyroid hormones. In pregnancy, TSH levels should typically be lower than non-pregnant levels, indicating a well-functioning thyroid. A TSH level of 4.5 mIU/L at 10 weeks gestation may indicate an abnormality in thyroid function and should be reported to the provider for further evaluation.