You can check your next possible day of donation with the donation date calculator.
If you want to donate blood, choose male or female based on your social security number.
When donating blood, the gender options are male or female. The gender of the blood donor is determined by the gender determined from the personal identification number. Information affects the safety of blood donation; e.g. to the minimum allowed intervals, hemoglobin limit values and the content of the health questionnaire.