Body Mass Index (BMI). Body Mass Index (BMI) is measure of body fat based on height and weight that applies to both adult men and women. BMI does not differentiate between body fat and muscle mass. Therefore, body builders and people who have a lot of muscle bulk will have a high BMI but are not overweight or obese.
The bump: or hematoma as we call it, can last for 1-2 weeks. Sometimes it gets slightly worse before it gets better. If the child is acting normally, and not vomiting uncontrollably, she should be fine. If she starts doing those things, call your pediatrician.
Not 100%: at 13 weeks genitals are still not very discernible; however some experiences sonographers could tell you whether its you are having a boy or a girl based on the position of the bump. My recommendation is to wait 17-20 weeks to be more assured of the sex of your baby. ...Read more.