A woman gets pregnant around the days when ovulation occurs. The average time of ovulation is the 14th day of an average length (28 day) menstrual cycle...since yours is 30 days cycles it will be +/-2 days....Ovulation time vary for each individual, and can occur from 12th to 19th day of the cycle . Sperm can live up to 3 to 5 days in a womans reproductive tract, so it is possible to become pregnant if unprotected sex occurs 5 days before ovulation. The life span of the typical egg is relatively short, only around 24 hours. If fertilization does not occur within that time frame, the egg will die...good luck..