Copper to Ceruloplasmin Ratio During Normal Pregnancy In Osogbo, Nigeria.

Abstract

Disordered copper and ceruloplasmin levels have been associated in pathologic pregnancies, however, investigation of copper status especially the determination of free copper which is the physiologically active fraction has been met with some difficulties. In this regard, the determination of copper/ceruloplasmin ratio has been proposed as one of the better indicators of copper status in pregnancy. Since copper/ceruloplasmin ratio varies from region to region, it has been advocated that each region determines its own cut-off. We therefore determined copper/ceruloplasmin ratio during normal pregnancy in Osogbo, SouthWestern Nigeria. 150 consenting pregnant women attending the antenatal Clinic of Ladoke Akintola University of Technology Teaching Hospital in different stages of gestation were recruited. Another 35 non pregnant age matched mothers were recruited as controls. 5 mls of venous blood was obtained from subjects and controls for the determination of serum copper with the aid of atomic absorption spectrophotometer and serum ceruloplasmin determined with a method based on its p- Phenylene Diamine Oxidase Activity according to the colourimetric method of Sunderman and Nomoto Copper in the first, second and third trimesters of pregnancy increases steadily and significantly compared with non pregnant subjects (36.72±3.75,46.88±0.02 and 58.13±2.50vs14.43±4.50imol/l, p significantly elevated above non pregnant controls, 47.21±8.88imol/l vs. 14.43±4.50imol/l p third trimesters increased significantly from each trimester and were significantly elevated above that of c o n t r o l s ( 4 9 . 5 6 ± 5 . 1 4 , 7 1 . 7 7 ± 7 . 0 7 a n d 90.70±2.77mg/100ml vs. 35.62±2.55mg/100ml, p trimester is significantly higher than in second and third trimesters while copper/ceruloplasmin ratios during second and third trimesters were similar. However, copper/ceruloplasmin ratio during first, second and third trimesters are significantly higher than in controls, 0.074 imol/g, 0.065 imol/g and 0.064 imol/g vs. 0.041 imol/g. Average copper/ceruloplasmin ratio in the total pregnant population was significantly higher than in controls 0.067 imol/g vs. 0.041 imol/g. Copper/ceruloplasmin ratio is highest during the first trimester and gradually decreases as pregnancy advances, this decrease may imply a decrease in available free copper to the fetus. Therefore a molecule of ceruloplasmin containing less than 0.064 imol/g of copper may suggest excess product ion of ceruloplasmin in relation to available copper which has been associated with pathologic pregnancies especially pre-eclampsia and eclampsia.