This version was machine-translated from German and has not been medically reviewed. The authoritative version is the German version.
Gestational age calculator
EDD, last menstrual period, birth, GA at birth → PMA, day of life, chronological and corrected age
About this calculator
From two known pieces of information (estimated due date, last menstrual period, gestational age at birth, date of birth, examination date), all others are calculated: gestational age at birth, estimated due date (EDD), first day of the last menstrual period (LMP), postmenstrual age, day of life (DOL), chronological and corrected age, date of the first ROP examination, and the conversion weeks+days ↔ days.
Frequently asked questions
How is gestational age determined from the estimated due date?
By calculation, the due date is 280 days after the first day of the last menstrual period. Gestational age at birth = 280 days minus the days between birth and due date (or plus, if birth occurred after the due date).
What is the difference between chronological, corrected and postmenstrual age?
Chronological age is the time since birth. Postmenstrual age is gestational age plus chronological age. Corrected age is chronological age minus the time missing up to 40+0 weeks – up to month 24 of life. Definitions according to AAP Committee on Fetus and Newborn 2004.
When is the first ROP examination due?
According to AAP 2018 at 31 weeks postmenstrual age or 4 weeks after birth – whichever is later. Screening is recommended for gestational age ≤ 30 weeks or birth weight ≤ 1500 g.