mother judging me not circumcising my baby

Important question mommas!!!!!: 

I'm pregnant with my first child and I will know the sex of my baby within the week or beginning of next week. I told my mother that if my husband and I have a boy we decided we are NOT going to circumcise him. She get very mad and said that I'm going to mess my child's life up, she also said to never expect him to be in any sport because he will be too insecure about not being circumcised. She also decided to say that girls would not be interested in him because he won't be circumcised. I'm very angry about this because I've looked facts up. Being not circumcised effects you just as much as being circumcised. I just don't know how to go about this, my mother is saying my child is gonna be made fun of and is gonna fail in life all because he won't be circumcised. I need opinions on this matter, being this is my first time having a kid....I know for a fact my husband and I do not want to circumcise our child, if you're born with it. It's meant to be there. I'm just not exactly sure how to go about what she has said to me about this, it makes me very upset. My husband and I are the parents I feel that she should support our decision regardless.