Usefulness of ultrasound fetal anthropometry in primary and secondary screening to identify small for gestational age: A meta-analysis.

PURPOSE: This study was performed to evaluate the usefulness of ultrasound fetal anthropometry in primary and secondary screening to identify small for gestational age (SGA).
METHODS: Ten databases, for example, PubMed (MEDLINE), were searched to include all English-language studies published since 2015 that provided true-positive and false-positive and true-negative and false-negative results of SGA identification. A bivariate diagnostic meta-analysis was performed to summarize the sensitivity and specificity as well as positive and negative likelihood ratios (PLR and NLR, respectively) of ultrasound fetal anthropometry for identification of SGA.
RESULTS: Sensitivity and NLR are important in primary screening. Both femur length and anthropometric formulas showed low sensitivity, although abdominal circumference showed moderate sensitivity. Abdominal circumference, femur length, and anthropometric formulas did not have sufficiently low NLR. However, specificity and PLR are important in secondary screening. Abdominal circumference, femur length, and anthropometric formulas all showed high specificity. Neither abdominal circumference nor femur length had sufficiently high PLR, but anthropometric formulas showed sufficiently high PNL.
CONCLUSIONS: Abdominal circumference, femur length, and anthropometric formulas are unsuitable in primary screening to identify SGA. However, anthropometric formulas, but not abdominal circumference and femur length, are useful in secondary screening to identify SGA.