Weekly tracking
Gestational age: decode weeks and trimesters
Calculate the exact week of pregnancy and learn which medical checks align with each stage.
What gestational age means
Gestational age counts weeks from the last menstrual period to organise labs, ultrasounds and check-ups. It differs from fetal age, which starts at conception.
Trimester snapshot
Weeks 1-12
First trimester
Organ formation and nausea control.
Weeks 13-27
Second trimester
Baby movements and the detailed anatomy scan.
Weeks 28-40
Third trimester
Faster growth and birth preparation.
Using the calculator
Provide the LMP or the gestational age from a recent ultrasound. The system returns the exact week, elapsed days and weeks remaining.
- Double check the date format (day/month/year).
- Update the value after each visit to keep a clear log.
- Write down relevant symptoms per week so you can discuss them during appointments.
Seek care immediately
Severe abdominal pain, vaginal bleeding or prolonged absence of fetal movements need urgent evaluation regardless of the week.
Sources

