[Daily variations in pregnancy hormones]

In a prospective study estriol, estradiol, progesterone, human placental lactogen (HPL) prolactin and SP1 (a placental glycoprotein specific for pregnancy), were performed in the second half of uncomplicated pregnancies in order to answer the question if there exist a circadian rhythm of these hormones in serum. All serum concentrations were measured by radioimmunoassay at 8.00, 10.00, 16.00, 20.00, 24.00 and 4.00 o'clock. 58 pregnant women with uncomplicated pregnancies show no circadian rhythm of serum levels from estriol, progesterone, HPL and SP1, while serum levels of estradiol and prolactin have a significant circadian rhythm. The estradiol serum levels are significant higher at 8.00 and 12.00 o'clock, significant less at 24.00 and 4.00 o'clock. The prolactin serum levels are significant less at 16.00 and 20.00, at 4.00 and 8.00 significant higher. In 20 pregnancies complicated by preeclampsia and 12 pregnancies complicated by intrauterine growth retardation serum levels of all hormones were measured at 8.00, 10.00, 16.00, 20.00, 24.00 and 4.00 o'clock. The serum concentrations in complicated pregnancies show no difference to the serum levels in uncomplicated pregnancies.