As far as I know there's no way to predict gender unless it's an ultra sound and you see it. You don't produce more of certain hormones depending on gender so I don't see how this could work. Don't waste your money girl just want a few weeks and get a gender revel ultrasound. Chances are even if you bought this you'd get an ultrasound either for a medical check up or a gender revel check up so you'd be spending double to get the same question answered