ICSI and thyroid trouble

[Janice]

I start sniffing on Monday, so went for blood taken last week to check FSH level. Phoned the clinic and they told me (very matter of factly) that I have an under active thyroid and I needed to see my GP for the right drugs before I start ICSI treatment. Saw GP yesterday - she hadn't received the letter from the clinic, so didn't know how under active, she was reluctant to give me the drugs until I cried, so she gave me lowest dose possible and will see me in a month!!!! I am now left high and dry! I don't really know what this means in terms of my ICSI treatment or what an under active thyroid really is anyway! Any advice welcome