I really don't know. One would assume that it would help lying down as gravity would assist it to get there quicker, but I doubt everyone who has gotten pregnant has done that? id say just lie down with pelvis tileted for about 5-10 mins afterwards and try to DTD so he finishes in you while your hips are elevated (I.e. Hips on a pillow or missionary, etc) I don't think there's any "proven" way (correct me if I'm wrong ladies! )