Trimester timeline: calculating pregnancy weeks to months - The Mother Baby Center
www.themotherbabycenter.org
Learn what to expect throughout pregnancy from the first weeks to the final months and how to prepare for delivery at The Mother Baby Center.

The time of pregnancy is calculated from the first day of your last menstrual period (LMP), which is typically two weeks before conception actually occurs. This means the first two weeks of the 40-week count are before fertilization, during which your body prepares for ovulation and a new cycle begins