Pregnancy actually begins before conception.
The first week of pregnancy countdown to birth begins at the start of your last menstrual period. Why? Because pinpointing exactly when your egg becomes fertilized is quite difficult, even for a doctor. So most doctors use an age estimation method called gestational age, instead of your baby’s actual fetal age. So let’s untangle the difference, shall we?
The first week of pregnancy countdown to birth begins at the start of your last menstrual period. Why? Because pinpointing exactly when your egg becomes fertilized is quite difficult, even for a doctor. So most doctors use an age estimation method called gestational age, instead of your baby’s actual fetal age. So let’s untangle the difference, shall we?
Gestational age calculates a due date by counting 40 weeks from the start of the mother’s last menstrual period. More precise. More consistent.
Fetal age begins when your egg is fertilized, which will be typically two weeks less than gestational age. So, when you're 8 weeks pregnant, your baby's fetal age is actually 6 weeks.