[Behavior of urinary estriol level before normal labor]

The levels of oestriol in urine of 30 healthy pregnant women in the last 22 to 25 days of pregnancy were determined and the statistical analysis was performed. It was found that the levels of oestriol in urine were the highest in 19-th and 9-th days before labour. This form of curve of oestriol levels was found to be characteristic for pregnant women before normal labour.