Follicle sizes at Baseline??

Amanda
When I went for my baseline U/S they told me that 3 follicles on my right side were at 10mm already (prob left over from last month). The rest were all Antral follicles. I'm on birth control now which is supposed to get all follicles to start at the same size but I'm worried that those 3 will take over! Has anyone else had this?