A study of circadian rhythms of estriol secretion in the third trimester of gestation complicated by gestosis and intra-uterine growth retardation (IUGR).

The circadian changes in serum estriol concentration in the case of gestosis (at 30-36 weeks gestation) and intra-uterine growth retardation-IUGR (at 28-36 weeks) were examined. The control group consisted of pregnant patients without placental insufficiency at 26-34 weeks gestation. No circadian rhythms of estriol secretion was found in patients with gestosis and IUGR, whereas such a rhythm was confirmed in normal pregnancies. The evaluation of circadian changes in estriol concentration in the third trimester of gestation may be useful when diagnosing chronic placenta insufficiency.