Efficacy of three ultrasonographic and six biochemical methods for the detection of intrauterine growth retardation were assessed in prospective studies of 40 cases associated with short uterine fundal height less than -1.5 SD and/or small ultrasonographically determined total intrauterine volume (TIUV) less than -1 SD of normal populations. Prenatal treatments, consisting of bed rest, high protein diet, intravenous drip infusion of 10% maltose, 500 ml per day, for more than 12 days, etc., were administered on them. Fifteen cases (37.5%) delivered small-for-date infants, 9 of which complicated by toxemia of pregnancy. At the final determinations, small TIUV were found in all small-for-date cases (100%), short biparietal diameter 80.0%, and short longitudinal intracavital uterine length 53.3% of 15 small-for-date cases. In biochemical parameters, low maternal plasma estriol levels were found in 73.3%, low plasma human placental lactogen levels 66.7%, low urinary estriol excretion 53.3%, abnormal plasma alpha-fetoprotein levels 33.3%, and low plasma progesterone levels 20.0% of 15 small-for-date cases. Nineteen cases (47.5%) demonstrated remarkable increases in TIUV following prenatal treatments, and delivered appropriate-for-date infants. Despite of marked growth in biophysical parameters, abnormal biochemical values were mostly not improved by these treatments.