Pregnancy Calculator
This calculator provides an estimated pregnancy schedule based on the due date, last period date, ultrasound date, conception date, or IVF transfer date.
Based on standard Naegele's rule (LMP + 280 days). Assumes a 28-day cycle.
How to Use the Pregnancy Calculator
Choose your input mode: enter the first day of your Last Menstrual Period (LMP), your known due date, or your estimated conception date. The calculator will compute your estimated due date, current gestational age, trimester, and conception date based on Naegele's rule.
Frequently Asked Questions
What is Naegele's Rule?+
Naegele's Rule estimates the due date by adding 280 days (40 weeks) to the first day of the last menstrual period. It assumes a regular 28-day cycle.
How accurate is this calculator?+
This provides an estimate. Only an ultrasound in the first trimester can confirm gestational age and due date with high accuracy.
What if my cycle is not 28 days?+
If your cycle is longer or shorter than 28 days, adjust the LMP date by the difference. For example, a 35-day cycle means ovulation is approximately day 21, so subtract 7 days from the LMP.
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