Note the First Day of the Last Menstrual Period (LMP): Start by determining the first day of the woman's last menstrual period. This is usually the first day of bleeding during the period.

Use an Online Due Date Calculator: If manual calculations seem difficult, consider using an online due date calculator. These calculators use algorithms to estimate the due date based on the first day of the last menstrual period.

Use an Online Due Date Calculator: If manual calculations seem difficult, consider using an online due date calculator. These calculators use algorithms to estimate the due date based on the first day of the last menstrual period

Consider Ultrasound Measurements: If an ultrasound is performed during the first trimester, the measurements of the embryo or fetus can provide a more accurate estimation of the due date. The ultrasound due date may differ slightly from the estimated due date based on the last menstrual period.

Keep Track of Pregnancy Milestones: Once the due date is determined, keep track of pregnancy milestones and appointments. It's crucial to monitor the progress of the pregnancy and address any concerns or questions with the healthcare provider.