I am 8 weeks pregnant,and had recently detected as high tsh after blood test.can it cause any problem to my baby.also what diet can be taken to normal?

Yes: You need to make sure you're not hypothyroid. Get the test repeated with the free hormones. If low, you need you treat. The baby needs thyroid hormone to optimally develop.

Hypothyroidism = a : High TSH with a low free T 4. Subclinical hypothyroidism = a high TSH with a free T 4 in the normal range. Both require treatment, as a fetus depends on maternal thyroxine till 12 wks., when it starts to synthesize its own. Thyroxine is important for organ development, especially that of the brain, that starts at 3 wks. post-conception. See an endocrinologist for diagnosis & management.