I finally got the nurse to test me on the 21 day.I dont know why they didnt want too. Im taking on clomid 100 mg.Im kind of nervous i heared it can cause you to have twins.Thats scary.Has anyone been on clomid and only concived 1 baby or had had twins. I start my clomid tomarrow the 21 and then wait till the 10 th day to start testing. thank linda