Can Thyroid Abnormality Trigger The Growth Of Fetus?

I have tested positive in the pregnancy test last Friday and yesterday we saw the Thyroid test report to be showing abnormal value for TSH of 17 where it should be 3.5. From my last menstrual cycle start it is now 46 days ( though I know the conception could only be a maximum of 40 days ago) and in the scan done yesterday the doctor says the foetus seen is only showing 35 day growth. This could be due to the thyroid causing delayed growth or the foetus having stopped growth due to the same or some reason. Also I had mild discharge yesterdy of brown period like strands, though very little. The doctor has adviced me to take some Thyroid medication and the following : Dufaston and Trenaxa 100 mg; and to wait till the next 10 days after which we can scan and see the growth and test TSH. If all is not well we may need to medically cleanse the uterus, as it is known that Thyroid abnormality may cause improper intellectual and other growth in the baby, or the baby may have stopped growing by then. I would like to take a second opinion and confirm we are on the right track, as either way it is a very important decision to make for us.