Re: what is meaning of T3,T4,TSH in medical terminology
T3 and T4 are thyroid hormones. T3 is the hormone which is the more active one in the body, though when one is being treated with oral medication, the replacement is usually with T4.
The TSH is thyroid-stimulating hormone and it is secreted from the pituitary gland after a signal from the hypothalamus though another hormone called TRH or thyrotropin releasing hormone.
TSH will be secreted in order to stimulate the thyroid, but if the thyroid stops being able to produce hormone for some reason or another, the TSH level will continue to rise in an effort to stimulate the thyroid more. So as the thyroid's function decreases, the TSH goes up. Normal TSH is usually in the range of 1-4. With yours being slightly elevated (meaning your thyroid function is every so slightly decreased) it puts you at risk of developing hypothyroidism in the future.
When pregnant, sometimes the thyroid can be affected and a person with otherwise normal thyroid function can have dysfunction. Your obstetrician will follow closely and if there are any derangements, you'll be sent to an endocrinologist. Fedup was right when she said that generally it is HYPERthyroidism which affects a pregnancy, but hypothyroidism can cause problems as well.