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Pregnancy Calculation Formula:
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The Pregnancy Calculator 9 Months estimates the due date based on the last menstrual period (LMP). It calculates that pregnancy typically lasts approximately 280 days or 9 months from the first day of the last menstrual period.
The calculator uses the standard pregnancy calculation formula:
Where:
Explanation: This calculation is based on Naegele's rule, which assumes a 28-day menstrual cycle and ovulation occurring on day 14.
Details: Accurate due date calculation is crucial for proper prenatal care, monitoring fetal development, planning for delivery, and identifying potential pregnancy complications.
Tips: Enter the first day of your last menstrual period in the date field. The calculator will provide your estimated due date, current pregnancy status, and days remaining until delivery.
Q1: How accurate is the 9-month calculation?
A: While pregnancy is commonly referred to as 9 months, it's actually 40 weeks or 280 days. Only about 5% of women deliver exactly on their due date.
Q2: What if my menstrual cycle is not 28 days?
A: For women with longer or shorter cycles, the calculation may need adjustment. Consult with your healthcare provider for a more accurate estimate.
Q3: When is the due date typically confirmed?
A: Due dates are often confirmed or adjusted during the first trimester ultrasound, which can provide more accurate dating.
Q4: What is considered full-term pregnancy?
A: Full-term pregnancy is between 39 weeks 0 days and 40 weeks 6 days. Early term is 37-38 weeks, late term is 41-41+6 weeks.
Q5: Can due dates change during pregnancy?
A: Yes, due dates may be adjusted based on ultrasound measurements, especially if there's a significant difference from the LMP-based calculation.