Finding out what the baby is..

KMorgan4710

I am not quite sure when i will find out what the gender of my baby is. I have had friends and family tell me that some women will find out what they are having at 12 weeks, and then others around the normal 18-20 weeks. Why is it that some women find out at 12 weeks instead of 20? Could it just be the doctor they go to, or what? This is my very first pregnancy, unexpected, because i'm only 17. I will be 18 in May and i just want to know as much as possible about everything. So please help me! It would be much appreciated!