Abstract
Objective. Audit screening properties of fundal height measures (FHM) in identifying fetal growth aberrations in low risk pregnancies in Norway. Design. A prospective cohort recruited for a controlled trial was retrospectively audited. Setting. Routine Norwegian antenatal care. Population. 789 women with singleton pregnancies. Methods. FHM were registered and dichotomized to positive or negative tests according to common practice. FHM were excluded from analysis in the low risk group from the day a risk factor that requires follow up of fetal growth by ultrasound measures was observed. Main outcome measures. SGA, FGR, LGA, sensitivity, specificity and predictive values of the FHM. Results. The sensitivity of screening for FGR by FHM in the low risk population was nil, as it was for SGA among overweight women. Among the lean and low risk women, the sensitivity for SGA seemed to be twice that of pure chance, but still capturing a mere 13% of SGA infants in this group of women. Compared with the screening by FHM alone, the clinical judgment only added marginal benefits to the specificity of screening for the low risk population. A negative FHM screening offered no reassurance compared with pure chance. In the screening for LGA in our population, clinician's judgment had much larger impact on the screening properties, mainly by being restrictive in referrals for large FHM, and thus reducing the overall sensitivity by half from 45 to 22%. Conclusion. The current reference curves and standards for FHM in Norway have poor screening properties and must be revised.