If you want to have some fun try the chinese gender prediction calender.
If you have other children you can even see if was would have been right. All you need to know is what month you conceived and the age at which you conceived.
Here is the link, http://www.babygenderprediction.com/chinese-gender-chart.html
FYI It was right for my first two, and according to it I'm expecting another beautiful little girl