Gestation Calculator LMP

Gestation Calculation Formula:

\[ Gestation = \left\lfloor \frac{\text{Current Date} - \text{LMP}}{7} \right\rfloor \]

Gestation:

Total Days:

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1. What is Gestation Calculation?

Gestation calculation determines the length of pregnancy in weeks and days based on the Last Menstrual Period (LMP). This is the standard method used by healthcare providers to estimate due dates and monitor fetal development.

2. How Does the Calculator Work?

The calculator uses the gestation formula:

\[ Gestation = \left\lfloor \frac{\text{Current Date} - \text{LMP}}{7} \right\rfloor \]

Where:

\( Current Date \) — The date for which you want to calculate gestation
\( LMP \) — First day of last menstrual period
\( \left\lfloor \right\rfloor \) — Floor function (rounding down to nearest whole number)

Explanation: The calculation determines the number of complete weeks between LMP and current date, plus any remaining days.

3. Importance of Gestational Age

Details: Accurate gestational age calculation is essential for prenatal care, determining due dates, monitoring fetal growth, scheduling tests, and making clinical decisions throughout pregnancy.

4. Using the Calculator

Tips: Enter the first day of your last menstrual period and the current date. The calculator will automatically compute gestation in weeks and days. Ensure dates are entered in the correct format (YYYY-MM-DD).

5. Frequently Asked Questions (FAQ)

Q1: Why use LMP instead of conception date?
A: LMP is more reliably known than conception date and is the standard method used worldwide for pregnancy dating.

Q2: How accurate is LMP-based gestation calculation?
A: Generally accurate within ±2 weeks. Ultrasound dating in first trimester is more precise and may be used to adjust dates if LMP is uncertain.

Q3: What if my cycles are irregular?
A: LMP dating assumes 28-day cycles. For irregular cycles, ultrasound dating in first trimester provides more accurate gestational age.

Q4: When should I calculate gestation?
A: Calculate at pregnancy confirmation and regularly throughout pregnancy to track progress and ensure appropriate prenatal care timing.

Q5: What is considered full term?
A: Full term is 39-40 weeks gestation. Delivery between 37-42 weeks is considered term, while before 37 weeks is preterm.