Gender Selection (IUI/IVF) PGD and Sperm Sorting with MicroSort and Ericsson. Gender Swaying. The 7 Sway Factors. Ultrasound Gender Prediction. Understanding the Nub Theory. More Gender Prediction. DNA Tests, Fetal Heart Rate, Chinese Gender Chart, the Drano Test, and more. Gender Odds. Odds of having another boy or girl. X Sperm and Y Sperm