If there is a gender component to risk of VR sickness, it seems likely it is related to some calibration factor being wrong due to differing head size - eg. The

If there is a gender component to risk of VR sickness, it seems likely it is related to some calibration factor being wrong due to differing head size - eg. The distance between the eyes, the center of rotation of the eyeballs, etc. I'm sure VR companies are working on it, because nausea isn't good for business...