Obstetric & Fetal Assessment
Every obstetric & fetal assessment calculator on CalcEngines — unit converters, derived indices and interpretive tools, each with its formula, a worked example and the reference intervals it is judged against.
6 calculators in this section
- Bishop Score CalculatorBishop's 1964 pelvic score out of 13, from the original five items — and the honest part: its discrimination for successful induction is modest, around 0.68 to 0.80 in published areas under the curve, well short of what its ubiquity implies.
- EFW Z-Score and Centile CalculatorThe z-score and the exact centile for an estimated fetal weight, against the reference mean and standard deviation from YOUR growth standard. The page holds no growth chart — it does the arithmetic the report leaves out.
- Fetal Growth Restriction Criteria InterpreterThe Delphi consensus definition of early and late fetal growth restriction, applied exactly as published. The two branches use different logic — early needs a size criterion AND a Doppler, late needs two of three — and that asymmetry is the point.
- Gestational Age from Crown-Rump LengthRobinson and Fleming's crown-rump length equation, in both of the two forms that circulate under that name, with its published accuracy. Refuses outside the 5 to 84 mm window it was derived in rather than extrapolating.
- Gestational Age from LMP CalculatorGestational age from the number of days since the first day of the last menstrual period, with Naegele's cycle-length adjustment and the days left to the 280-day estimate. Days in, days out: this page has no calendar.
- Hadlock Estimated Fetal Weight CalculatorAll four Hadlock EFW regressions, computed exactly from their published coefficients, with their live disagreement and the honest accuracy: a 95% interval wider than 14% of birth weight, which is why an EFW is not a weight.