The growth areas in fetal assessment in late pregnancy have been studied by making a quantitative review of the papers in four obstetric journals. Of the 130 relevant papers published, in 1973, the most common subject treated was the phospholipid test of fetal lung maturity. Other important tests reviewed were estrogen assays, ultrasonic studies, human placental lactogen and alpha-fetoprotein measurements. The clinical value of phospholipid tests was demonstrated; liquor creatinine assays are much inferior in assessing fetal maturity. Plasma estriol assays are likely to be of increasing importance in clinical practice. Some caution should be applied in the interpretation of ultrasonic measurements of biparietal diameter as a test of fetal development and well-being.
