1. What Is Pregnancy Weeks Calculator?

The Pregnancy Weeks Calculator estimates gestational age based on the last menstrual period (LMP). It calculates how many weeks pregnant you are by determining the time elapsed since your LMP.

2. How Does The Calculator Work?

The calculator uses the following formula:

Where:

• \( \text{LMP} \) — Last menstrual period date
• \( \text{Current Date} \) — Today's date or specified date
• \( \left\lfloor \right\rfloor \) — Floor function (rounds down to nearest whole number)

Explanation: The calculation counts the number of complete weeks that have passed since the first day of your last menstrual period.

3. Importance Of Pregnancy Dating

Details: Accurate pregnancy dating is essential for monitoring fetal development, scheduling prenatal tests, determining due date, and making important medical decisions throughout pregnancy.

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 determine how many weeks pregnant you are as of that date.

5. Frequently Asked Questions (FAQ)

Q1: Why is pregnancy calculated from LMP instead of conception?
A: LMP is used because it's typically easier to recall than the exact conception date, and it provides a standardized method for healthcare providers worldwide.

Q2: How accurate is LMP-based dating?
A: LMP dating is generally accurate for women with regular 28-day cycles. For irregular cycles, ultrasound dating may be more precise.

Q3: What if I don't know my exact LMP?
A: If you're unsure of your LMP, an early pregnancy ultrasound (usually between 6-12 weeks) can provide the most accurate gestational age estimation.

Q4: Does this calculator account for leap years?
A: Yes, the calculator automatically accounts for leap years and varying month lengths in its date calculations.

Q5: Can I use this for IVF pregnancies?
A: For IVF pregnancies, gestational age is typically calculated from the embryo transfer date plus 14 days, not from LMP.