Serum Vitamin D and Calcium Status in Pregnant Women in Calabar, Southern Nigeria
Main Article Content
Abstract
Background: Vitamin D3 is a micronutrient that is essential for calcium homeostasis, especially during pregnancy, where there is high formational physiologic demand. In most antenatal care settings in developing countries, vitamin D and calcium assays are not part of routine practice during clinic visits. This study aimed to assess the current status of maternal serum vitamin D and calcium among antenatal care attendees.
Methods: The study design was cross-sectional, with the use of a systematic random sampling method to recruit antenatal care clinic attendees. The enzyme-linked Immunosorbent Assay (ELISA) method was used to assay for vitamin D3, while the automated spectrophotometer enzymatic method was used to estimate serum calcium. Data was entered and analyzed using SPSS version 26.0. Fisher’s Exact, independent t-test, and Pearson correlation analysis were used as inferential statistics. P-value was set at 0.05.
Results: Two hundred and twenty-four (224) subjects were studied, with a mean age of 29.0 ± 4.8 years. The median (IQR) serum level of vitamin D was 36.6 (37.1) nmol/l. and 37.5% had insufficient (17.9%) or deficient (19.6%) levels. Mean serum calcium was 1.78 ± 0.49 mmol/l, and approximately three-quarters (76.4%) of subjects had (subclinical) hypoglycemia. There was a significant positive correlation between gestational age and serum vitamin D, as well as an inverse correlation between systolic blood pressure (SBP) and serum levels of vitamin D (p<0.05).
Conclusions: Antenatal clinic consultations should consider vitamin D assay for high-risk pregnant women, as well as emphasize dietary counseling for vitamin D supplementation and/or intake of vitamin D-rich foods.
Downloads
Article Details
Section
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
The Journal is owned, published and copyrighted by the Nigerian Medical Association, River state Branch. The copyright of papers published are vested in the journal and the publisher. In line with our open access policy and the Creative Commons Attribution License policy authors are allowed to share their work with an acknowledgement of the work's authorship and initial publication in this journal.
This is an open access journal which means that all content is freely available without charge to the user or his/her institution. Users are allowed to read, download, copy, distribute, print, search, or link to the full texts of the articles in this journal without asking prior permission from the publisher or the author.
The use of general descriptive names, trade names, trademarks, and so forth in this publication, even if not specifically identified, does not imply that these names are not protected by the relevant laws and regulations. While the advice and information in this journal are believed to be true and accurate on the date of its going to press, neither the authors, the editors, nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein.
TNHJ also supports open access archiving of articles published in the journal after three months of publication. Authors are permitted and encouraged to post their work online (e.g, in institutional repositories or on their website) within the stated period, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access). All requests for permission for open access archiving outside this period should be sent to the editor via email to editor@tnhjph.com.
How to Cite
References
1.Sun M, Wu X, Yu Y, Wang L, Xie D, Zhang Z et al. Disorders of Calcium and Phosphorus metabolism and the proteomes/metabolomics – based research. Front Cell Dev Biol 2020;8: 576110. doi:10.3389/fcell.2020.576110
2.Purswani JM, Gala P, Dwarkanath P, Larkin HM, Kurpad A, Mehta S. The Role of Vitamin D in Pre-eclampsia: a systematic review. BMG Pregnancy Childbirth 2017; 17(1):231 doi: 10.1186/s12884-017-1408-3.
3.Donati S, Marini F, Giusti F, Palmini G, Aurilia C, Falsetti I et al. Calcifediol: why, when, how much? Pharmaceutical (Basel) 2023; 16(5): 637. doi: 10.3390/ph16050637
4.Dovnik A, Mujezinovic F. The Association of Vitamin D Levels with Common Pregnancy Complications. Nutrients 2018; 10(7):867 doi:103390/nu10070867
5.Pilz S, Zittermann A, Obeid R, Hahn A, Pludowski P, Trummer C et al. The Role of Vitamin D in Fertility and during Pregnancy and Lactation: A Review of Clinical Data. Int J Environ Res Public Health 2018:15(10): 2241.doi:10.3390/ijerph15102241
6.Fiscaletti M, Stewart P, Munns C. The Importance of Vitamin D in Maternal and Child health: a global perspective. Public Health Rev 2017: 38(19) doi:/10.11.86/s40985-017-0066-3
7. Palacios C, Kostiuk LL, Cuthbert A, Weeks J. Vitamin D Supplementation for Women during Pregnancy. Cochrane Database Syst Rev 2024; 7(7): CD008873. https//doi.org/10.1002/14651858. Published online 2024 Jul 30. Last assessed on March 14, 2026
8.Triunfo S, Lanzone A. Potential Impact of Maternal Vitamin D Status on Obstetric Well-being. J Endocrinol Invest 2016;39(1):37-44 doi:10.1007/s40618-015-0330-7
9.Khalessi N, Kalani M, Araghi M, Farahani Z. The Relationship between Maternal Vitamin D Deficiency and Low Birth Weight Neonates. J Family Reprod Health 2015;9(3):113-117. PMID: 26622309. PMCID: PMC4662754
10.Tabesh Marjan, Salehi-Abargouei A, Tabesh Maryam, Esmaillzadeh A, Maternal Vitamin D Status and Risk of Pre-eclampsia: a systematic review and meta-analysis. The J of Clin Endocrinol & Metab August 2013;98(8):3165-3173 https://doi.org/101210/jc.2013-1257
11.Van der Pligt P, Willcox J, Szymlek-Gay EA, Murray E, Worsley A, Daly RM. Associations of Maternal Vitamin D Deficiency with Pregnancy and Neonatal Complications in Developing Countries: a systematic review. Nutrients May 2018;10(5):640 doi:10.3390/nu10050640
12.Sahu MT, Sahu M. Vitamin D Replacement in Pregnant Women in Developing Countries. In: Watson RR (ed) Handbook of Vitamin D in Human Health. Human Health Handbooks, vol. 5, Wageningen Academic Publishers, Wageningen. https://doi.org/10.3920/978-90-8686-765-3-3p
13.Aji AS, Erwinda E, Yusrawati Y, Malik SG, Lipoeto NI. Vitamin D Deficiency Status and its Related Risk Factors during Early Pregnancy: a cross-sectional study of pregnant Minankubau women, Indonesia. BMC Pregnancy Childbirth May 2019 22;19(1): 183.doi:10.1186/s12884-019-2341-4
14.Diaz-Lopez A, Jardi C, Villalobos M, Serrat N, Basora J, Arija V. Prevalence and Risk Factors of Hypovitaminosis D in Pregnant Spanish Women. Sci Rep 2020; 10(1): 15757 doi:10.1038/s41598-020-71980-1
15. Holick MF, Binkley NC, Bischoff-Ferrari HA, Gordon CM, Hanley DA, Heaney RP, et al. Evaluation, Treatment, and Prevention of Vitamin D Deficiency: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab 2011; 96:1911-1930 https://doi.org/10.1210/JC-2011-0385
16.WMA statement on vitamin D insufficiency. Adopted by the 66th WMA General Assembly, Moscow, Russia, World Medical Association, 2015.https: www.wma.net>wmj20150
17.Fan H, Hui L, Yan X, Hou W, Bai E, Wan L et al. Serum 25-hydroxyvitamin D levels and affecting factors among preconception fertile women. BMC Women's Health 2020; 20: 146. doi: 10.1186/s12905 -020 – 01018 – 1
18.Voulgaridou G, Papadopoulou SK, Detopoulou P, Psoumana D, Giaginis C, Kondyli FS et al. Vitamin D and calcium in osteoporosis and the role of bone turnover markers: A narrative review of recent data from RCTs. Diseases 2023; 11(1): 29. doi: 10.3390/ diseases 11010029
19.Gerede A, Papasozomenou P, Stavros S, Potiris A, Domali E, Nikolettos N et al. Calcium supplementation in pregnancy: A systematic review of clinical studies. Medicina 2025; 61 (7): 1195. https://doi.org/10.3390/medicina61071195
20.Charan J, Biswas T. How to calculate sample size for different study designs in medical research? Indian journal of psychological medicine. 2013;35(2):121-126. doi:10.4103/0253-7176.116232
21.Brian-D Adinma JI, Ahaneku JE, Adinma ED, Ugboaja JO, Egeonu RO, Edet MM. Vitamin D status and its influence on pregnancy outcomes amongst pregnant women in southeastern Nigeria. World Journal of Advanced Research and Reviews. 2020;7(2): 089-098.doi:10.30574/wjarr.2020.7.2.0264
22.Owie E, Afolabi BB. Vitamin D Deficiency in Pregnant Women and Newborns in Lagos, Nigeria. J Obstet Gynaecol 2018 Jul; 38(5): 616-621.doi:10.1080/0144361.2017.1396299
23.Oluwole AA, Okunade KS, Okojie OE. Maternal serum vitamin D levels and preterm delivery among low-risk parturients in Lagos, Nigeria. Int J. Gynaecol obstet 2019; 144(2):216-220 doi:10.1002/ijgo.12719.
24.Gbadagesin A, Sobande A, Adedeji O et al. Maternal serum vitamin D levels and pregnancy outcomes from Lagos, Nigeria. J Obstet Gynaecol 2017 Jan; 37(1):25-28. Doi:10.1080/0143615.2016.1196483
25.Ahmed F. Khasravi-Boroweni H., Khan MR, Roy AK, Raqib R. Prevalence and predictors of vitamin D deficiency and insufficiency among pregnant rural women in Bangladesh. Nutrients 2021 Jan 29;13(2): 449.doi:10.3390/nu13020449
26.Fondjo LA, Tashie W, Owiredu WKBA, Adu-Gyamfi EA, Seidu L. High prevalence of vitamin D deficiency among normotensive and hypertensive pregnant women in Ghana. BMC Pregnancy Childbirth 2021 April 26;21(1):331. Doi:10.1186/s12884-021-03802-9
27.Al –Faris NA. High prevalence of vitamin D deficiency among pregnant Saudi women. Nutrient 2016 Feb 4; 8(2):77. Doi:10.3390/nu8020077
28.Institute of Medicine. Dietary Reference Intakes for calcium and vitamin D. Washington DC: The National Academies Press (US); 2011. doi:10.17226/13050 PMID: 21796828
29.McCartney CR, McDonnell ME, Corrigan MD, Lash RW. Vitamin D insufficiency and epistemic humility: An Endocrine Society guideline communication. The J Clin End & Metab 2024; 109: 1948 – 1954. https://doi.org/10.1210/clinem/dgae322
30.Eyong EM, Omoronyia EE, Eyong M, Ekpe L, Ikobah J, Odusolu P. Knowledge, attitude and practice of vitamin D intake among pregnant women in Calabar: Implications for maternity care in the tropics. Ibom Med J 2025; 18(3): 424 – 431. doi: 10.61386/imj.v.18i3.700
31.Larqué E, Morales E, Leis R, Blanco-Carnero JE. Maternal and fetal health implications of Vitamin D status during pregnancy. Ann Nutr Metab 2018;72(3): 179-192 .https://doi.org/10.1159/000487370
32.Burkhary NBI, Isa ZM, Shamsuddin K, Lin KU, Mahdy ZA, Hassan H, et al. Risk Factors for antenatal hypovitaminosis D Deficiency in an urban district in Malaysia. BMC Pregnancy Childbirth 2016:16. https://doi.org/10.1186/s12884-016-0939-3
33. Karadeniz V. Ozpamuk-Karadeniz F. Ahbab S, Ataoglu E, Can G. Vitamin D deficiency is a potential risk factor for blood pressure elevation and the development of hypertension. Medicine (Kaunas) 2021; 57(12):1297. Published online 2021 Nov. 25. Doi:10.3390/medicina57121297
34.Kokkinari A, Antoniou E, Orovou E, Andronikidi PE, Tzitiridou – Chatzopoulou M, Sarantaki A et al. The role of vitamin D supplementation in preventing pre-eclampsia: A review of randomized controlled trials with meta – analysis. Healthcare 2025; 13(11): 1221. https: //doi.org/10.3390/healthcare13111221
35.Karras S, Paschou SA, Kandaraki E, Anagnostis P, Annweiler C, Tarlatzis BC et al Hypovitaminosis D in pregnancy in the Mediterranean region: a systematic review. Eur J Clin Nutr 2016;70(9): 979-986. Doi:10.1038/ejcn.2016.12