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OB Wheel: Pregnancy calculator

OB Wheel




Easy to use Multi-function pregnancy calculator. Created by a board-certified OBGyn.

This app is also available as a web app at

Calculate dates of pregnancy:
- Last menstrual period (LMP)
- Estimated date of conception
- Estimated gestational age (EGA)
- EGA obtained by ultrasound
- Dating by IVF Embryo transfer
- Calculate gestation by Crown-Rump length
- Estimated due date (EDD)

Additional features:
- "Time Machine" mode can calculate "How many weeks will patient be on xxxx date?" and "When will patient be xx weeks gestation?"
- Adjust length of cycle and luteal phase
- Store multiple patients for easy retrieval
- Include extra notes in patient data
- Export/import your saved data
- Full Help pages

This app calculates exactly 280 days (40 weeks) from LMP to EDC, and accordingly for any date in between. Please note that the paper/plastic wheels used by obstetricians or ultrasound technicians are inherently inaccurate. Different pregnancy wheels may vary by as much as 3 or 4 days. Please keep this in mind when comparing the values obtained here to those given in clinics/hospitals.
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