1. What is the UK NHS Due Date Calculator?

The UK NHS Due Date Calculator estimates the expected delivery date based on the last menstrual period (LMP) using the standard NHS formula of LMP + 280 days. This provides an accurate estimation for pregnancy planning and prenatal care.

2. How Does the Calculator Work?

The calculator uses the UK NHS standard formula:

Where:

• \( LMP \) — Last Menstrual Period (start date)
• \( 280 days \) — Standard pregnancy duration (40 weeks)

Explanation: This calculation method is based on the assumption of a 28-day menstrual cycle and is the standard method used by the UK National Health Service for estimating due dates.

3. Importance of Due Date Calculation

Details: Accurate due date estimation is crucial for proper prenatal care scheduling, monitoring fetal development, planning maternity leave, and preparing for delivery.

4. Using the Calculator

Tips: Enter the first day of your last menstrual period in the date field. Ensure the date is accurate for the most reliable due date estimation.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is the NHS due date calculation?
A: The NHS calculation is highly accurate for women with regular 28-day cycles. Only about 5% of babies are born exactly on their due date.

Q2: What if my cycle is longer or shorter than 28 days?
A: For cycles longer than 28 days, add the extra days to the due date. For shorter cycles, subtract the difference. Consult your healthcare provider for personalized calculation.

Q3: When will I have my dating scan?
A: The NHS typically offers a dating scan between 8-14 weeks of pregnancy to confirm the due date.

Q4: Can the due date change after calculation?
A: Yes, your due date may be adjusted after your dating scan if the measurements differ significantly from the LMP-based calculation.

Q5: What is considered full term?
A: A pregnancy is considered full term between 37-42 weeks. Babies born before 37 weeks are premature, while those after 42 weeks are post-term.