I m 32 yrs old and have no chind. I have thyroid problem since last 4 months and initially dr. prescribed levothyroxin 25mg and after two months he increased my dosage to 50 mg. For third month I took 50 mg tablet everyday. But in fourth month i got the refill of 25mg which i didnot noticed earlier. And while taking 25mg dose i notice that I have missed my period. I dont think m pregnant. So is that the affact of Dosage change? Please help.