A normal menstrual cycle interval is considered 21-35 days and is calculated from the first day of full flow until the next month’s first day of full flow. In practical terms, a normal cycle interval is 24-34 days with minimal variation among cycles, namely 2-3 days. While regular ovulation (the release of a mature egg from an ovary) results in monthly menstrual cycles, regular monthly bleeding does not always result from ovulation.
Fortunately, monthly cycles will assist a couple in conceiving particularly with the assistance of an ovulation predictor kit to signal impending release of the egg. Studies have shown when a couple has daily to every other day intercourse within the six days preceding ovulation then they have the highest chance of conceiving. Irregular menstrual cycles are often a sign of a hormonal balance so prompt consultation with your doctor is recommended.