Pregnancy Calculator
Calculate due date and track pregnancy milestones
Calculate Based On
Date Information
Cycle Information
days
days
Your Pregnancy Results
Based on your provided information
January 20, 2025
Week 12 of 40
First Trimester
Based on Last Menstrual Period
Pregnancy Timeline
Pregnancy Trimesters
| Trimester | Weeks | Key Developments | Common Symptoms |
|---|---|---|---|
| First | 1-13 | Organ formation, heartbeat begins | Morning sickness, fatigue |
| Second | 14-26 | Rapid growth, movement felt | Increased energy, back pain |
| Third | 27-40 | Final development, weight gain | Shortness of breath, swelling |
About Pregnancy Calculation
Pregnancy is typically calculated from the first day of your last menstrual period (LMP), which is about 2 weeks before conception actually occurs. A full-term pregnancy is about 40 weeks from the LMP.
Calculation Methods
| Method | Description | Accuracy |
|---|---|---|
| Last Menstrual Period (LMP) | Based on first day of last period | Standard method, ±2 weeks |
| Due Date | Calculate conception and LMP from due date | Reverse calculation |
| Conception Date | Based on actual conception date | More accurate if known |
| Ultrasound Dating | Based on early ultrasound measurements | Most accurate method |
| IVF Transfer Date | Based on embryo transfer date | Very accurate for IVF pregnancies |
Important Notes
- Only about 5% of babies are born on their exact due date
- Most births occur between 37 and 42 weeks
- This calculator provides estimates - always consult with your healthcare provider
- Individual pregnancies may vary based on many factors