Endocrine Abstracts

Introduction: Cord blood gases are measured following partition and are used as surrogate markers in the assessment of fetal oxygenation status at delivery and in identification of risk for neonatal encephalopathy. Low maternal prolactin levels were associated increased risk of respiratory distress syndrome. This study measured cord blood prolactin levels and correlated values with blood gases to examine possible value in assessment of fetal stress during delivery.

Methods: Cord blood samples (n=73) were collected following blood gases analysis, serum separated by centrifugation and stored at -20°C until further analysis. Prolactin levels were measured using DueSet ELSIA (R and D Systems, MN, USA). Samples diluted (1:400) prior to analysis.

Results: Cord blood prolactin levels ranged from 51 to 6108 mIU/l (median 2467 mIU/l). Blood gases parameters ranged from pH 7.14 to 7.49 (median 7.31), pO2 from <29 to 47 (median 33 mmHg), pCO2 from 24 to 77, (median 48 mmHg), and bicarbonate from 16 to 29 (median 23 mmol/l). None of the samples exhibited pH<7.0 which would correlate with adverse neonatal outcome. Prolactin levels were slightly negatively correlated with pH values but not significant, whereas no correlation was observed with pO2 nor with pCO2(P>0.8). Prolactin levels slightly negatively correlated with bicarbonate (P<0.06). Maternal age at delivery ranged from 18 to 42 (median 27 years).DiscussionThe acidotic cord blood pH reflects the increased oxygen utilization and increased pCO2 elimination. Overall, there was poor correlation between cord blood prolactin levels and blood gases. However, there was slight difference in mean prolactin levels between samples with pH<7.27 and those with pH between 7.34 and 7.27. Additional studies are required to further elucidate the clinical utility of measuring cord blood prolactin.