ABNORMAL UMBILICAL ARTERY DOPPLER WAVE-FORMS AND CORD-BLOOD CORTICOTROPIN-RELEASING HORMONE

Objective: To determine whether placental secretion of corticotropin-r eleasing hormone into the fetal circulation is increased in pregnancie s complicated by umbilical-placental vascular insufficiency. Methods: Twenty women with abnormal Doppler umbilical artery flow velocity wave forms and six women with uncomplicated term pregnancies and normal umb ilical artery now velocity waveforms had cord blood concentrations of corticotropin-releasing hormone, ACTH, cortisol, and beta-hCG estimate d. Results: The mean cord blood colticotropin-releasing hormone concen tration was significantly higher in pregnancies with abnormal umbilica l artery now velocity waveforms than in normal pregnancies (108 +/- 27 versus 24 +/- 8 pg/mL, P =.019). Elevated cord blood corticotropin-re leasing hormone levels were seen in the abnormal group regardless of t he presence or absence of preeclampsia or fetal growth restriction. Th ere were no significant differences in cord blood cortisol, ACTH, or b eta-hCG concentrations. Conclusion: The concentration of corticotropin -releasing hormone in the fetal circulation is significantly increased in pregnancies complicated by abnormal umbilical artery now velocity waveforms. This may represent a stress-responsive compensatory mechani sm in the human placenta.