1. What is Pregnancy Weeks Calculation?

The pregnancy weeks calculation determines how far along a pregnancy is by measuring the time elapsed since the first day of the last menstrual period (LMP). This is the standard method for dating pregnancies in clinical practice.

2. How Does the Calculator Work?

The calculator uses the following simple formula:

Where:

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

Explanation: The calculation counts the number of days between two dates and converts them to weeks by dividing by 7.

3. Importance of Pregnancy Dating

Details: Accurate pregnancy dating is crucial for proper prenatal care, timing of tests, monitoring fetal growth, and determining the due date (approximately 40 weeks from LMP).

4. Using the Calculator

Tips: Enter the first day of your last menstrual period and the current date (or any date you want to check). The calculator will show how many weeks and days have passed since your LMP.

5. Frequently Asked Questions (FAQ)

Q1: Why is pregnancy counted from LMP rather than conception?
A: LMP is used because it's a clearly identifiable date, while conception date is often unknown. Pregnancy is typically 38 weeks from conception but 40 weeks from LMP.

Q2: What if I don't know my LMP date?
A: An ultrasound in early pregnancy (especially first trimester) can provide an accurate estimate of gestational age.

Q3: Does this work for irregular cycles?
A: The calculation assumes a standard 28-day cycle. Women with irregular cycles may need ultrasound dating for accuracy.

Q4: How accurate is this method?
A: When LMP is known and cycles are regular, it's quite accurate in first trimester. Accuracy decreases as pregnancy progresses.

Q5: What's considered full term?
A: Full term is 39-40 weeks. Babies born between 37-38 weeks are early term, and after 41 weeks is late term.