Surveillance of the diabetic pregnancy with antepartum fetal nonstress testing and urinary estriol excretion.

The value of daily fetal heart rate (FHR) nonstress test (NST) and 24-hour urinary excretion of estriol (E3) were compared in a consecutive series of 76 diabetic pregnancies. The NST scoring system (0-10 points) employed included monitoring of fetal movements in addition to evaluation of FHR decelerations, accelerations as well as frequency and amplitude of oscillations. Patients were delivered electively after 38 weeks of gestation unless spontaneous labor began earlier or if delivery was indicated for either maternal reasons or presumed fetal distress. Fetal distress was believed to be present if two consecutive NST scores were 6 points or less. Seven patients had a day-to-day E3 fall of 50% or more at least once. Six of these patients had normal NST scores and 5 of the infants showed no signs of asphyxia at delivery. Forty-two patients had E3 drops of 30-50% and 27 patients had E3 drops of less than 30%; in contrast, the NST scores were 6 or less in 15 patients but were normal the next day. These data indicate that measurements of urinary excretion of E3 give many false alarms of fetal jeopardy and that daily NST can replace measurement of urinary excretion of E3 and reduce unwarranted intervention and unnecessary prematurity.