ABSTRACT
We developed a computer-generated algorithm for standardizing the assignment of a
best gestational age. Our database collected information on maternal last menstrual
period (LMP), prenatal ultrasonography, obstetrical estimated date of confinement
(EDC), use of assisted reproductive technology (ART), and newborn assessment based
on the Ballard examination. The algorithm for determining best gestational age was
developed based on the literature on the accuracy of prenatal and neonatal dating.
We examined the performance of the algorithm using patients admitted to our neonatal
intensive care unit (NICU) with a best gestational age ≤ 32 completed weeks. Based
on agreement of the obstetric EDC with either the first-trimester ultrasonography
or LMP and first- and second-trimester ultrasonography, 64.4% of patients were classified
as having certain dating. The Ballard assessment played a role in assigning a best
gestational age in 11.3% of patients. We demonstrated differences in outcomes based
on dating certainty within subpopulations in our NICU. An objective standardized methodology
for assigning gestational age is a useful tool for comparing gestational age-based
outcome measures between institutions.
KEYWORDS
Algorithm - standardizing gestational age measurement
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Jack JacobM.D.
Pediatrix Medical Group/Alaska Neonatology
3340 Providence Drive, Anchorage, AK 99502
