1. What is Gestational Age?

Gestational age is the common term used during pregnancy to describe how far along the pregnancy is. It is measured in weeks from the first day of the woman's last menstrual period (LMP) to the current date.

2. How Does the Calculator Work?

The calculator uses the standard medical formula:

Where:

• LMP — First day of last menstrual period
• Current Date — Today's date or assessment date
• 7 — Days per week conversion factor

Explanation: This calculation provides the most accurate estimate when the woman has regular menstrual cycles and is certain of her LMP date.

3. Importance of Gestational Age Calculation

Details: Accurate gestational age determination is crucial for proper prenatal care, timing of tests, evaluating fetal growth, and determining the due date.

4. Using the Calculator

Tips: Enter the first day of the last menstrual period and the current date (defaults to today). The calculator will compute the gestational age in weeks.

5. Frequently Asked Questions (FAQ)

Q1: What if I don't know my LMP?
A: If LMP is unknown or cycles are irregular, an ultrasound measurement in early pregnancy (first trimester) provides the most accurate dating.

Q2: How accurate is this method?
A: For women with regular 28-day cycles who are certain of their LMP, this method is accurate to within ±3-5 days in the first trimester.

Q3: What's the difference between gestational age and fetal age?
A: Gestational age counts from LMP (about 2 weeks before conception), while fetal age counts from conception. Gestational age is always about 2 weeks more.

Q4: When should I see a doctor for pregnancy confirmation?
A: Schedule a prenatal visit when you have a positive pregnancy test, typically around 8 weeks gestational age by LMP.

Q5: What if my cycle isn't 28 days?
A: For cycles longer than 28 days, add the difference to the gestational age. For example, with 35-day cycles, add 1 week to the calculated gestational age.