1. What is Pregnancy Dating?

Pregnancy dating calculates how far along a pregnancy has progressed, typically measured in weeks from the first day of the last menstrual period (LMP). This is the standard method used by healthcare providers to track pregnancy progress.

2. How Pregnancy Calculation Works

The calculator uses the standard pregnancy dating formula:

Where:

• LMP — First day of last menstrual period
• Current Date — Today's date or any date you want to check

Explanation: Pregnancy is calculated from the first day of your last period, not from conception. A full-term pregnancy is about 40 weeks (280 days) from LMP.

3. Importance of Accurate Dating

Details: Accurate pregnancy dating is crucial for proper prenatal care, scheduling tests at the right times, monitoring fetal development, and determining 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 show how many weeks pregnant you are and your estimated due date.

5. Frequently Asked Questions (FAQ)

Q1: Why count from LMP instead of conception?
A: LMP is more reliably known than conception date for most women, so it's become the standard reference point.

Q2: What if I don't know my LMP?
A: An ultrasound in early pregnancy can estimate gestational age based on fetal measurements.

Q3: Are all pregnancies exactly 40 weeks?
A: No, 40 weeks is an average. Normal pregnancies can range from 37-42 weeks.

Q4: What if my cycles aren't regular?
A: The calculation assumes a 28-day cycle. If your cycles are longer/shorter, adjustments may be needed.

Q5: When should I see a doctor?
A: Schedule your first prenatal visit as soon as you get a positive pregnancy test.