Do you go by the gestational age or fertilization age?

In clinical settings, gestational age is typically used to track pregnancy development, which measures the time from the first day of the last menstrual period (LMP) rather than the time of fertilization. Gestational age is generally about two weeks longer than fertilization age, which counts from the actual date of conception. However, both measurements are important in different contexts, such as in fertility treatments or prenatal care. Ultimately, gestational age is the standard for most medical discussions and assessments.