|Year : 2011 | Volume
| Issue : 4 | Page : 408-412
Copper and selenium status of healthy pregnant women in Enugu, southeastern Nigeria
UI Nwagha1, SO Ogbodo2, EE Nwogu-Ikojo1, DM Ibegbu3, FE Ejezie3, TU Nwagha4, CC Dim1
1 Department of Physiology/Obstetrics and Gynecology, College of Medicine, University of Nigeria, Enugu campus, Nigeria
2 Department of Medical Laboratory Science, College of Medicine, Health Sciences, Ebonyi State University, Abakaliki, Nigeria
3 Department of Medical Biochemistry, College of Medicine, University of Nigeria, Enugu campus, Nigeria
4 Department of Hematology and Immunology, College of Medicine, University of Nigeria, Enugu campus, Nigeria
|Date of Acceptance||02-Apr-2011|
|Date of Web Publication||12-Jan-2012|
U I Nwagha
Department of Physiology/Obstetrics and Gynecology, College of Medicine, University of Nigeria, Enugu campus
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: Copper and selenium are important trace elements in man. They function as antioxidants and play roles in oxido-reductase reactions. Several imported multivitamin preparations are given to our women during pregnancy and lactation to correct possible deficiencies.
Objective: The aim of the study is to determine the serum level of these micronutrients (selenium and copper) in a cross section of pregnant women in Enugu, southeastern Nigeria.
Materials and Methods: A cross section of 130 healthy pregnant women at different trimesters of pregnancy and 30 non-pregnant controls were selected from two health facilities in Enugu, southeastern Nigeria. Serum from the samples collected was assayed for copper and selenium using atomic absorption spectrophotometer.
Results: The mean copper level increased (P = 0.018), while the selenium level decreased (P < 0.0001) as pregnancy advanced.
Conclusion: High copper levels indicate that supplementation should not be undertaken during normal pregnancy. Dietary intake should be modified to ensure optimal selenium levels during pregnancy.
Keywords: Copper, Nigeria, pregnancy, selenium
|How to cite this article:|
Nwagha U I, Ogbodo S O, Nwogu-Ikojo E E, Ibegbu D M, Ejezie F E, Nwagha T U, Dim C C. Copper and selenium status of healthy pregnant women in Enugu, southeastern Nigeria. Niger J Clin Pract 2011;14:408-12
|How to cite this URL:|
Nwagha U I, Ogbodo S O, Nwogu-Ikojo E E, Ibegbu D M, Ejezie F E, Nwagha T U, Dim C C. Copper and selenium status of healthy pregnant women in Enugu, southeastern Nigeria. Niger J Clin Pract [serial online] 2011 [cited 2020 Feb 17];14:408-12. Available from: http://www.njcponline.com/text.asp?2011/14/4/408/91745
| Introduction|| |
Copper is an essential trace element, which has been found to be an important constituent of vital enzymes, especially those functioning as antioxidants and as oxido-reductases. , Copper deficiency is rare, but cases have been identified in humans, which manifested as neutropenia,  anemia and skeletal abnormalities,  with atherogenic and electrocardiographic irregularities,  and is linked to low birth weight of neonates.  Different studies have reported high serum copper levels during normal pregnancy. , These changes are steady and consistent from the first trimester to third trimester. ,
Selenium is an essential antioxidant trace mineral for the human body. It is a component of selenoproteins such as the antioxidant enzyme glutathione peroxidase (GSHPx), which protects human tissue from damage by hydrogen peroxide, lipid peroxides and free radicals.  Thus, it is invaluable in the protection of the tissues against oxidative stress. Furthermore, it is very useful for healthy human growth and reproduction, and is important in the metabolism of thyroid hormones.  Wide variations in selenium levels occur in humans. Geographical location, soil content, intake of selenium in diet and its bioavailability significantly affect selenium status.  There have been varying reports on the selenium status during pregnancy, with various studies showing lower levels in pregnancy. , However, studies in Spain and Japan observed no differences in serum selenium levels between healthy pregnant and non-pregnant women. ,
Low selenium status has been associated with pre-eclampsia, , increased incidences of intrahepatic cholestasis,  gestational and pre-gestational diabetes,  and recurrent pregnancy loss. , Indeed, low selenium status is associated with an acceleration of HIV disease progression among HIV-1 infected pregnant women.  In addition, a low plasma selenium level is associated with increased risk of fetal death, child death and increased risk of intrapartum mother-to-child transmission of HIV. 
In our environment, there is no doubt that nutritional deficiency is prevalent in pregnancy. It thus became a common practice to routinely supplement iron and folic acid with the aim of preventing anemia in pregnancy. However, the role of other micronutrients in the prevention of anemia and oxidative damage to red cell membrane has received little attention. Consequently, maternal and perinatal mortality and morbidity remained unacceptably high despite global efforts to curb the trend. In an attempt to improve the situation, our caregivers resorted to the practice where all sorts of micronutrient replacements are administered, without recourse to the peculiar micronutrient needs necessitated by our varied socioeconomic, cultural and geographic environment. The resultant effect was the infiltration of the Nigerian market with numerous multivitamin and mineral preparations with diverse and varying compositions. It thus became pertinent that we should determine the serum level of some of the micronutrients (copper and selenium) in our healthy pregnant women to assist in the optimal formulation of micronutrient needs suitable for our environment.
| Materials and Methods|| |
The study was done in Enugu, the capital of Enugu State in southeastern Nigeria, between January and October 2009. The city of Enugu is situated at about 230 m above sea level. The population of the city is about 464,514 of which 52.1% are females. Enugu State has a crude birth rate of 45 per 1000, crude death rate of 18 per 1000 of the population and a life expectancy of 51 years.  The maternal mortality rate ranges between 750 and 850 per 100,000 live births. , Commonly eaten foods in Enugu include rice, yam, cassava, beans, corn food, egusi, ogbono, orah and vegetable soups.
This was a cross-sectional study involving 130 healthy pregnant women in various trimesters of pregnancy (34 in first trimester, 44 in second trimester and 52 in third trimester), attending antenatal clinic at two health care facilities in Enugu (one secondary and one tertiary). The control group was made of 30 healthy non-pregnant women recruited from the staff of the health institutions. All the subjects were selected by simple random sampling using a lucky dip of YES or NO. They were matched for age and social class. The parity range was between zero and four. Subjects with febrile conditions, multiple pregnancy, pre-eclampsia, diabetes mellitus, chronic renal disease, sickle cell anemia and HIV infections were excluded from the study. After obtaining ethical clearance and informed verbal consent, healthy pregnant women were recruited. Medical and obstetric histories were obtained. The gestational age was assessed from the first day of the last normal menstrual period in completed weeks of gestation. Trimester was defined as first trimester (<14 weeks), second (14-27 weeks) and third (>27 weeks). All the women were on routine iron and folic acid only, but not on copper and selenium supplementation. The socioeconomic class was determined by the method of Szreter.  All the subjects belonged to the middle class. A 24-hour dietary recall dialog was conducted to estimate their dietary copper, selenium and calorie intake. In this method, the subjects were required to recall their individual exact food intake during the previous 24-hour period or the preceding day. Also recorded were detailed descriptions of all foods and beverages consumed, including cooking methods and brand names (where possible). The amount of caloric as well as copper and selenium contents were estimated using the nutrient composition of commonly eaten staple foods in Nigeria  and other parts of the world.  Medical and obstetric examinations were performed. The weight was measured to the nearest 0.5 kg using a standard weighing scale. All the subjects and controls were subjected to the same instrument and method of measurement.
About 5 ml venous blood from the ante-cubital vein was collected from the subjects using sterile, disposable syringes into sterile, plain tubes. Samples for the non-pregnant group were collected on the 5th day of their menstrual cycle after an early morning negative pregnancy test. The blood samples were allowed to stand for about 30 minutes to clot and then centrifuged at 3500 rpm for 15 minutes. The serum was collected and kept frozen at −20°C until analyzed.
Analyses were done within 2 weeks of sample collection using atomic absorption spectrophotometer (AAS/AES Model 205) (Buck Scientific , East Norwalk, Conneticut USA ).
Values were recorded as mean and standard deviation. Comparison of mean was by one-way analysis of variance (ANOVA) followed by multiple comparisons with Tukey's honestly significant post-hoc test.
Ethical clearance was obtained from the university hospital ethical committee and verbal informed consent was got from all participants.
| Results|| |
[Table 1] shows some demographic characteristics and estimated daily calorie, copper and selenium intake of the women. They were approximately on same nutrient intake. There were no statistically significant differences in parity (P = 0.542). [Table 2] shows the mean copper and selenium levels in the control and across the three trimesters of pregnancy. The mean copper level increased (P = 0.018), while the selenium level decreased (P < 0.0001) as pregnancy advanced. [Table 3] shows Tukey's honestly significant post-hoc test multiple comparisons.
|Table 1: Some demographic characteristics/Estimated daily nutrient intake|
Click here to view
|Table 3: Multiple comparisons of differences of means between the variables (Turkey, s honestly significant post hoc)|
Click here to view
| Discussion|| |
Progressive rise in concentrations of maternal serum copper from first trimester to third trimester was observed in this study, with statistically significant difference observed only between the third trimester and the controls. This trend has been shown in many other studies from different countries ,, and has been associated with increase in blood estrogens and decreased biliary excretion which is common in pregnancy. ,
The relationship between copper and iron has been a subject for debate. It has been shown that iron supplementation in pregnant women (with hemoglobin greater that 13.2 g/dL) significantly reduced serum copper concentrations in both second and third trimesters.  Furthermore, Ghosh et al. reported higher serum copper concentration in anemic pregnant women than in non-anemic ones in both second and third trimesters. This supported the view that iron has the potency of inducing negative copper concentrations or limiting its bioavailability in pregnancy. This phenomenon should be taken into cognizance during the treatment of iron deficiency anemia.
The selenium levels seen in this study indicate the selenium status of women in southeast Nigeria to be adequate when compared to other studies. , However, the serum selenium concentration decreased linearly from non-pregnant controls and as pregnancy progressed. Studies have shown that selenium levels are significantly lower in healthy pregnant women (especially in the second and third trimesters) than in healthy non-pregnant women. , Some studies have however produced conflicting reports. , Several reasons may be responsible for the lower levels found in this study. Active transfer of selenium from maternal blood to the tissues of the developing fetus has been advocated.  Indeed, hemodilution due to increased plasma volume in pregnancy further depletes selenium concentration. Additionally, inadequate intake and storage in the maternal tissues and increased demand by the growing fetus invariably leads to low maternal levels during pregnancy.
While this study population consists mainly of urban dwellers who may have a varied diet including bread from imported wheat, the results may not be the same for rural dwellers where poor farm practices, heavy tropical rains, and erosion may cause trace elements to be leached out of the soil. In addition, the staple foods in the rural areas are mainly tubers (especially cassava) which are not known to contain high levels of selenium. However, a study in Anambra State, also in southeast Nigeria,  comparing Oba town to Nanka (a town prone to erosion), did not show statistically different mean values for selenium in both communities.
High copper levels, as observed in this study, had led to the recommendation by the Institute of Medicine of Washington DC, USA, that copper supplementation should not be undertaken during normal pregnancy.  Low levels of selenium suggest that dietary modification be advocated to meet the needs of pregnant and lactating mothers. Where dietary modifications are not possible, supplementation may be advocated. Despite this, majority of the prenatal drugs used in our environment still contain copper in appreciable amounts with little or no selenium.
In developing countries, it seems maternal malnutrition will continue to be a key contributor to unpleasant reproductive outcomes, in spite of efforts to fortify foods or distribute medicinal supplements to pregnant women. Consequently, all forms of micronutrient supplementation have been advocated. These formulations come in all forms of sizes and shapes, with various and varying micronutrient compositions, and with diverse claims of superiority among the competing importers and manufacturers. As a result, our pregnant women ingest all forms of chemicals in the name of routine drugs.
Currently, practitioners are advocating the use of a single daily dose micronutrient supplement in order to enhance compliance. Good as this maybe, allowing drug manufacturers and importers to indiscriminately compound drugs, without recourse to peculiar socioeconomic, geographical and biochemical variables, may spell doom for feto-maternal health. Our practitioners and caregivers should thus discourage our pregnant women from taking those supplements that contain copper as this may provoke overload. Conversely, selenium-rich foods or, when applicable, supplements, should be encouraged while formulating nutritional policies during pregnancy and lactation.
This study did not evaluate the effect of short birth to pregnancy interval on the levels of the micronutrients. In addition, it may be possible that routine iron and folic acid taken by these women will have affected selenium absorption. These issues, as well as determining the reference values for our environment, need to be addressed in future studies. Indeed, larger longitudinal studies in pregnant Nigerian women would also be needed to further validate our findings. Additionally, the effect of these biochemical changes on pregnancy outcome needs further investigation. A 1-month dietary recall gives a better dietary history than a 24-hour method; however, this is very cumbersome and difficult to comply by the subjects.
Maternal malnutrition has attracted little concern from the authorities and this attitude may not be unrelated to the continued adverse feto-maternal outcomes in our environment. Nutritional needs of our pregnant women should be streamlined to enable optimal replacements if we must attain the millennium developmental goals.
| References|| |
|1.||Jaiser SR, Winston GP. Copper deficiency myelopathy: Review. J Neurol 2010;257:869-81. |
|2.||Copper Information: Benefits, Deficiencies, Food sources. Available from: http://www.healthvitaminsguide.com/minerals/copper.htm [Last assessed on 2011 Feb23]. |
|3.||Klevay LM. "Myelodysplasia," myeloneuropathy, and copper deficiency. Mayo Clin Proc 2006;81:132. |
|4.||Kumar N. Copper deficiency myelopathy (human swayback). Mayo Clin Proc 2006;81:1371-84. |
|5.||Ford ES. Serum copper concentration and coronary heart disease among US Adults. Am J Epidemiol 2000;151:1182-8. |
|6.||Giles E, Doyle LW. Copper in extremely low-birth weight or very preterm infants. Am Acad Pediatr 2007;8:159-64. |
|7.||Gambling L, Danzeisen R, Fosset C, Andersen H, Dunford S, Srai K, et al. Iron and copper interactions in development and the effect on pregnancy outcome. J Nutr 2003;133:1554S-6S. |
|8.||McArdle HJ. The metabolism of copper during pregnancy - a review. Food Chem 1995;54:77-84. |
|9.||Onwuamaze IC, Okereke SN, Ugonabo MC. Serum copper and ceruloplasmin levels in pregnant, lactating and non-pregnant Nigeria women. Orient J Med 2003;15:9-12. |
|10.||Martin-Lagos F, Navarro-Alarcon M, Terres Martos C, Lopez-GarciadelaSerrana C, Perez-Valero V, Lopez-Martinez MC. Zinc and copper concentrations in serum Spanish women during pregnancy. Biol Trace Elem Res1998;61:61-70. |
|11.||Burk RF. Selenium, an antioxidant. Nutri Clin Care 2000;5:75-9. |
|12.||Patrick L. Selenium biochemistry and cancer: A review of the literature. Altern Med Rev 2004;9:239-58. |
|13.||Wasowicz W, Gromadzinska J, Rydzynski K, Tomczak J. Selenium status of low-selenium area residents: Polish experience. Toxicol Lett 2003;137:95-101. |
|14.||Schulpis KH, Karakonstantakis T, Gavrili S, Chronopoulou G, Karikas GA, Vlachos G, et al. Maternal - neonatal serum selenium and copper levels in Greeks and Albanians. Eur J Clin Nutr 2004;58:1314-8. |
|15.||Mihailoviæ M, Cvetkoviæ M, Ljubiæ A, Kosanoviæ M, Nedeljkoviæ S, Jovanoviæ I, et al , Selenium and malondialdehyde content and glutathione peroxidase activity in maternal and umbilical cord blood and amniotic fluid. Biol Trace Elem Res 2000;73:47-54. |
|16.||Navarro M, López H, Pérez V, López MC. Serum selenium levels during normal pregnancy in healthy Spanish women. Sci Total Environ 1996;186:237-42. |
|17.||Karita K, Takano T, Satoh K, Suzuki T. Variations in plasma selenium levels as a result of the menstrual cycle and pregnancy in healthy Japanese women. Biol Trace Elem Res 2004;99:83-91. |
|18.||Rayman MP, Bode P, Redman CW. Low selenium status is associated with the occurrence of the pregnancy disease pre-eclampsia in women from the United Kingdom. Am J Obstet Gynecol 2003;189:1343-9. |
|19.||Mistry HD, Wilson V, Ramsy MM, Symonds ME, Pipkin FB. Reduced selenium concentrations and glutathione peroxidase activity in preeclamptic pregnancies. Hypertension 2008;52:881-8. |
|20.||Reyes H, Báez ME, González MC, Hernández I, Palma J, Ribalta J, et al. Selenium, zinc and copper plasma levels in intrahepatic cholestasis of pregnancy in normal pregnancies and in healthy individuals in Chile. J Hepatol 2000;32:542-9. |
|21.||Hawkes C, Alkan Z, Lang K, King J. Plasma selenium decrease during pregnancy is associated with glucose intolerance. Biol Trace Elem Res 2004;100:19-29. |
|22.||Kumar KS, Kumar A, Prakash S, Swamy K, Jagadeesan V, Jyothy A. Role of red cell selenium in recurrent pregnancy loss. J Obstet Gynaecol 2002;22:181-3 |
|23.||Desai P, Patel P, Rathod SP, Mahajan S. Selenium levels and glutathione peroxidase activity in spontaneous inevitable abortion. J Obstet Gynecol India 2006;56:311-4. |
|24.||Fawzi WW. Selenium status is associated with accelerated HIV disease progression among HIV-1 infected pregnant women in Tanzania. J Nutr 2004;134:2556-60. |
|25.||Kupka R, Garland M, Msamanga G, Spiegelman D, Hunter D, Fawzi W. Selenium status, pregnancy outcomes, and mother-to-child transmission of HIV-1. J AcquirImmune Defic Syndr 2005;39:203-10. |
|26.||State Ministry of Health, Enugu Health Sector Reform: Implementing the District Health System. Posted 2004. Available from: http://www.enugustate.gov.ng/. [Last assessed on 2010 Aug 30]. |
|27.||Onah HE, Okaro JM, Umeh U, Chigbu CO. Maternal mortality in health institutions with emergency obstetric care facilities in Enugu State, Nigeria. J Obstet Gynaecol 2005;25:569-74. |
|28.||Ezugwu EC, Onah HE, Ezugwu FO, Okafor 2 nd . Maternal Mortality in a Transitional Hospital in Enugu, South East Nigeria. Afr J Reprod Health 2009;13:67-72. |
|29.||Szreter SR. The Official representation of social classes in Britain, the United States and France: The Professional Model and "Les Cadres"', Comp Stud Soc Hist 1993;35:285-317. |
|30.||Oguntano EB, Akinyele IO. Nutrient composition of commonly eaten foods in Nigeria; raw, processed and prepared. Ibadan, Nigeria: Food Basket foundation Publication series; 1995. |
|31.||Paul AA, Southgate DA. The composition of foods. 4 th ed. London: Her Majesty Stationery Office (HMSO); 1979. |
|32.||Al-Bader A, Hussain T, Al-Mosawi M, Otaibi M, Abul H, Khalifa D, et al. Serum zinc and copper concentrations in pregnant women from Kuwait. J Trace Elem Exp Med 1997;10:209-15. |
|33.||Awadallah SM, Abu-Elteen KH, Elkarmi AZ, Qaraein SH, Salem NM, Mubarak MS. Maternal and cord blood serum levels of zinc, copper and iron in healthy pregnant Jordanian women. J Trace Elem Exp Med 2004;17:1-8. |
|34.||Oscalatunbosun DA, Adadedoh DK, Adeniyi FA. Serum copper in normal pregnancy in Nigerians. Br J Obstet Gynaecol 2005;81:475-6. |
|35.||Veena R, Narang AP, Baday AW, Bhan VK. Copper and zinc levels in maternal and fetal cord blood. Int J Gynaecol Obstet 1991;35:47- 9. |
|36.||Ziaei S, Janghorban R, Shariatdoust S, Faghihzadeh S. The effect of iron supplementation on serum copper and zinc levels in pregnant women with high-normal haemoglobin. Int J Gynaecol Obstet 2008;100:133-5. |
|37.||Ghosh UK, Jabin M, Merma M, Dayal M, Mehrotra R, harma DJ. Role of trace elements in anemia in pregnancy. Obstet Gynecol India 2007;57:410-2. |
|38.||Molnar J, Garamvolgyi Z, Herold M, Adanyi N, Somogyi A, Rigo J. Serum selenium concentrations correlate significantly with inflammatory biomarker high-sensitive CRP levels in Hungarian gestational diabetic and healthy pregnant women at mid-pregnancy. Biol Trace Elem Res 2008;121:16-22. |
|39.||Olife IC, Okaka AN, Dioka CE, Meludu SC, Orisakwe OE. Iodine status and the effect of soil erosion on trace elements in Nanka and Oba towns of Anambra State, Nigeria. Ann Chim 2007;97:895-903. |
|40.||Institute of Medicine. Nutrition during pregnancy. Washington DC: National Academy Press; 1990. |
|41.||Makola D, Ash DM, Tatala SR, Latham MC, Ndossi G, Mehansho H. A micronutrient-fortified beverage prevents iron deficiency, reduces anemia and improves the hemoglobin concentration of pregnant tanzanian Women. J Nutr 2003;133:1339-46. |
[Table 1], [Table 2], [Table 3]
|This article has been cited by|
||Serum Selenium Level in Early Healthy Pregnancy as a Risk Marker of Pregnancy Induced Hypertension
| ||Malgorzata Lewandowska,Stefan Sajdak,Jan Lubinski |
| ||Nutrients. 2019; 11(5): 1028 |
|[Pubmed] | [DOI]|
||Associations of Internal-Migration Status with Maternal Exposure to Stress, Lead, and Selenium Deficiency Among Pregnant Women in Shanghai, China
| ||Shiwei Jiang,Bo Yang,Jian Xu,Zhiwei Liu,Chonghuai Yan,Jinsong Zhang,Shufang Li,Xiaoming Shen |
| ||Biological Trace Element Research. 2018; |
|[Pubmed] | [DOI]|
||Toxics (Pb, Cd) and trace elements (Zn, Cu, Mn) in women during pregnancy and at delivery, South Benin, 2014–2015
| ||Marine Guy,Manfred Accrombessi,Nadine Fievet,Emmanuel Yovo,Achille Massougbodji,Barbara Le Bot,Philippe Glorennec,Florence Bodeau-Livinec,Valérie Briand |
| ||Environmental Research. 2018; 167: 198 |
|[Pubmed] | [DOI]|
||Study of the influencing factors of the blood levels of toxic elements in Africans from 16 countries
| ||Luis Alberto Henríquez-Hernández,Octavio P. Luzardo,Luis D. Boada,Cristina Carranza,José Luis Pérez Arellano,Ana González-Antuña,Maira Almeida-González,Carlos Barry-Rodríguez,Manuel Zumbado,María Camacho |
| ||Environmental Pollution. 2017; 230: 817 |
|[Pubmed] | [DOI]|
||Zinc and copper status in childbearing age Tunisian women: Relation to age, residential area, socioeconomic situation and physiologic characteristics
| ||Myriam El Ati-Hellal,Radhouene Doggui,Abderrazek Hedhili,Pierre Traissac,Jalila El Ati |
| ||Chemosphere. 2016; 149: 231 |
|[Pubmed] | [DOI]|
||Low serum selenium concentration is associated with preeclampsia in pregnant women from Bangladesh
| ||Md. Mahmodul Haque,Md. Mizanur Rahman Moghal,Md. Shahid Sarwar,Shamima Nasrin Anonna,Mariyam Akter,Palash Karmakar,Salma Ahmed,MA Sattar,Mohammad Safiqul Islam |
| ||Journal of Trace Elements in Medicine and Biology. 2016; 33: 21 |
|[Pubmed] | [DOI]|