Urinary total oestrogen values determined by an automated method in normal and abnormal pregnancies

Area of Science:

• Reproductive Endocrinology
• Maternal-Fetal Medicine
• Clinical Chemistry

Background:

• Accurate assessment of fetal well-being during late pregnancy is crucial.
• Urinary total estrogen levels serve as a potential biomarker for fetal health.
• Establishing normal ranges and understanding deviations are vital for clinical interpretation.

Purpose of the Study:

• To determine the normal range of urinary total estrogen values in late pregnancy.
• To investigate the correlation between urinary total estrogen levels and fetal outcomes, including fetal growth and viability.
• To evaluate the utility of an automated fluorimetric method for estrogen determination.

Main Methods:

• Automated fluorimetric method utilizing the Kober reaction and Ittrich extraction.
• Analysis of 360 urine samples from 56 pregnant patients at term (40 weeks gestation).
• Statistical analysis including logarithmic transformations to establish probability bounds.

Main Results:

• The mean urinary total estrogen value at 40 weeks gestation was 52.6 mg/24 h, with 95% probability bounds of 29.1 and 95.3 mg/24 h.
• "Small for dates" fetuses in good condition were associated with estrogen levels generally below the normal mean.
• Significantly low estrogen values (below or approaching 10 mg/24 h) were strongly linked to fetal demise, except in cases of normal growth with mechanical delivery complications.

Conclusions:

• Urinary total estrogen levels provide valuable insights into fetal well-being in late pregnancy.
• Low estrogen concentrations are indicative of compromised fetal growth or impending fetal death.
• The automated fluorimetric method is reliable for quantifying urinary total estrogens in obstetric practice.