Home Back

Gestational Age Calculator

Gestational Age Formula:

\[ \text{Gestational Age} = \frac{\text{Current Date} - \text{Last Menstrual Period (LMP)}}{7} \]

Unit Converter ▲

Unit Converter ▼

From: To:

1. What is Gestational Age?

Gestational age is a measure of the age of a pregnancy from the first day of the last menstrual period (LMP). It is typically expressed in weeks and days. This measurement helps healthcare providers monitor fetal development and schedule important prenatal tests.

2. How Does the Calculator Work?

The calculator uses the standard gestational age formula:

\[ \text{Gestational Age} = \frac{\text{Current Date} - \text{Last Menstrual Period (LMP)}}{7} \]

Where:

Explanation: The calculation counts the number of days between the LMP and current date, then converts this to weeks and days.

3. Importance of Gestational Age Calculation

Details: Accurate gestational age determination is crucial for proper prenatal care, including timing of ultrasounds, screening tests, and evaluating fetal growth. It also helps determine the estimated due date.

4. Using the Calculator

Tips: Enter the first day of your last menstrual period and the current date (defaults to today). The calculator will determine how many weeks and days pregnant you are.

5. Frequently Asked Questions (FAQ)

Q1: What if I don't know my LMP?
A: If you're unsure of your LMP, an ultrasound in early pregnancy can help estimate gestational age based on fetal measurements.

Q2: Does this work for IVF pregnancies?
A: For IVF pregnancies, gestational age is typically calculated from the egg retrieval date or embryo transfer date, not LMP.

Q3: What's the difference between gestational age and fetal age?
A: Gestational age counts from LMP, while fetal age counts from conception (typically 2 weeks less than gestational age).

Q4: How accurate is this calculation?
A: This method assumes a regular 28-day cycle with ovulation on day 14. Variations in cycle length may affect accuracy.

Q5: When should I see a doctor for pregnancy confirmation?
A: Schedule your first prenatal visit when you have a positive pregnancy test, typically around 8 weeks gestational age.

Gestational Age Calculator© - All Rights Reserved 2025