Now that science has found a ovulation inducing factor (OIF)in human semen, we may now know why the Rhythm method has a high failure rate. http://www.wired.com

Now that science has found a ovulation inducing factor (OIF)in human semen, we may now know why the Rhythm method has a high failure rate. http://www.wired.com/2012/08/semen-ovulation-fertility/ http://www.wired.com/2012/08/semen-ovulation-fertility/