Main Article Content
Background: Though most pregnant women tend to deliver around their expected date of confinement, quite a significant number deliver preterm and postterm. The variation of delivery timing can result from obstetrics complications, genetic or demographic factors.
Objective: The objective of this study is to determine the influence of demographic factors of pregnant Ijaw women on gestational age at delivery, like: maternal age, parity, occupation, educational level, gestational age at booking, maternal height, and body mass index, on gestational age at delivery. It also intends to determine the effects of birth weight and fetal sex.
Materials and Methods: It was an observational cross-sectional study of 1484 booked pregnant women of Ijaw ethnic group, who delivered in the labour ward of the Niger Delta University Teaching Hospital. Their case notes were retrieved and relevant information such as maternal age, parity, educational level, and occupation was obtained. Others include maternal height and weight at booking, gestational age at booking, gestational age at delivery and birth weight. Body mass index was calculated from height and weight and categorized. Data was analyzed with Chi square, Pearson’s correlation coefficient, simple linear regression, and multivariate analysis
Results: The prevalence of preterm birth (PTB) among Ijaw women was 9.7%, and the prevalence of PTB was significantly associated with underweight, Odd ratio = 7.79[3.12, 19.50], low educational level, Odd ratio =2.27[1.40, 3.68], and late booking for antenatal care P = 0.004. Delivery postterm was significantly associated with class 1 obesity, Odd ratio =16.0[4, 59, 55.8], and delivery of male babies Odds ratio = 6.76[2.41, 18.96].
Demographic factors from multivariate analysis could only account for 15.9% of the factors responsible for gestational age at delivery, of which the most important were birth weight, educational level and maternal height at booking.
Conclusion: Though maternal and fetal demographic factors significantly affects birth weight, the bulk of the determinants (84.1%) are outside these factors, and it could be from obstetrics, genetic, or other factors.
Mittendorf R, William MA, Berkey CS, Cotter PF. Length of uncomplicated human gestation. Obstetrics and Gynecology.1990;75(6):929-32.
Committee opinion No. 700. Definition of term pregnancy. ACOG. 2017; 129:150–4.
Brook Kaylyn. Impacts of birth plans on maternal satisfaction a literature review and focus group study. Senior Honors project. 2010; 309:37-8.
Azeez B, Chinyere E, Osayame E, Nancy W, Jenna L, Iretiola F et al. Characteristics and risk factors of preterm births in a tertiary center in Lagos, Nigeria. PAMJ. 2016; 24:1-8.
Blessing C Umeigbo, Ifeoma A Modebe, Ifeoma C Iloghalu, George U Eleje, Chukwuemeka C Okoro, Osita S Umeononihu, Ekene A Emeka. Outcomes of preterm labor and preterm births: A retrospective cross- sectional analytical study in a Nigerian single center population. Obstetrics and Gynecology Research. 2020; 3(1):17-28.
Aregawi G, Assefa N, Mesfin F et al. Preterm births and associated factors among mothers who gave birth in Axum and Adwa Town public hospitals, Northern Ethiopia. BMC Res Notes 12. 2019; 640.
Tanyous EEN, Abdalla SM, Hakem EHR. Prevalence and risk factors of preterm births in the National Ribat University Teaching Hospital, North Sudan. Obstet Gynecol Int J. 2015; 2(1):39-41.
Robert L Goldenberg, Jennifer F Culhane, Jay D Iams, Roberto Romero. Epidemiology and causes of preterm birth. Lancet. 2008; 371:75–84.
Mokuolu OA, Suleiman B, Adesiyun O, Adeniyi A. Prevalence and determinants of pre-term deliveries in the University of Ilorin Teaching Hospital, Ilorin, Nigeria. Pediatr Rep. 2010; 2(1).
Fuchs F, Monet B, Ducruet T, Chaillet N, Audibert F. Effect of maternal age on the risk of preterm birth: A large cohort study. PLoS ONE. 2018;13(1):1–10. e0191002.
Gebrekiros A, Nega A, Firehiwot M, Fissaha T, Tesfay A, Mussie M, Guesh G. Preterm births and associated factors among mothers who gave birth in Axum and Adwa Town public hospitals, Northern Ethiopia. BMC Res Notes. 2019; 12: |640.
Ahern J, Pickett KE, Selvin S, Abrams B. Preterm birth among African American and white women: A multilevel analysis of socioeconomic characteristics and cigarette smoking. J Epidemiol Community Health. 2003;57:6–11.
Caughey A. What is the optimal gestational age for delivery? J Perinatol. 2006;26:387–8.
Geneva Foundation of Medical Education and Research. Normal labour. Edited by Aldo Campana; 2019.
Julie M Harrison. The initiation of labour: Physiological mechanisms. BJM. 2013; 8(5).
Galal M, Symonds I, Murray H, Petraglia F, Smith R. Postterm pregnancy. Facts Views Vis Obgyn. 2012;4(3):175-87.
International statistical classification of diseases and related health problems, 10th revision. Geneva (CH): World Health Organization, 5th Edition; 2016.
Kui D, Yan H, Yanping W, Jun Z, Yi M, Xiaohong L, Aiyun X et al. Prevalence of postterm births and associated maternal risk factors in China: Data from over 6 million births at health facilities between 2012 and 2016. Scientific Reports. 2019; 9:273.
Nathalie R, Lena S, Gunvor E, Helle K, Olof S. Maternal risk factors for postterm pregnancy and cesarean delivery following labor induction. Acta Obstetricia et Gynecologica. 2010;89:1003–10.
Emuveyan EE. Prolonged pregnancy. In: Comprehensive obstetrics in the tropics. Edited by Kwawukume E. Y, Emuveyan E. E. 1st edition. 2002;135-9.
Kirsti Myklestad, Lars Johan Vatten, Elisabeth Balstad Magnussen, KjellÅsmund Salvesen, Pål Richard Romundstad. Do parental heights influence pregnancy length? A population-based prospective study, HUNT 2. BMC Pregnancy Childbirth. 2013;13:33.
Louis J. Aronne. Classification of obesity and assessment of obesity-related health risks. Obesity Research. 2002;10(2):105-14.
Shahi A, Dabiri F, Kamjoo A, Yabandeh AP, Khademi Z, Davaridolatabadi N. Association between body mass index (BMI) and duration of pregnancy in women referred to Shariati Hospital in Bandar Abbas. Electron Physician. 2017;9(1): 3611-15.
Derraik J. G, Lundgren M, Cutfield WS, Ahlsson F. Maternal Height and Preterm Birth: A study on 192,432 Swedish Women. PLoS One. 2016;11(4):e0154304.
Kurz, Christoph F et al. The causal influence of maternal obesity on preterm birth. The Lancet. Diabetes & Endocrinology. 2020; 8(2):101–3.
Slack E, Best KE, Rankin J, Heslehurst N. Maternal obesity classes, preterm and post-term birth: A retrospective analysis of 479,864 births in England. BMC Pregnancy Childbirth. 2019;19(1):434.
Ntenda PAM. Association of low birth weight with undernutrition in preschool-aged children in Malawi. Nutr J. 2019; 18(51).
Iyoke CA, Lawani LO, Ezugwu EC, Ilo KK, Ilechukwu GC, Asinobi IN. Survival of singleton preterm babies may not depend on maternal risk factors for preterm births. Nigerian Journal of Clinical Practice. 2015; 18( 6):74 -9.
Divan MY, Ferber A, Nisell H, et al. Male gender predisposes to prolongation of pregnancy. Am J Obstet Gynecol. 2002; 187:1081-3.
Mead PB, Marcus SL. Prolonged pregnancy. Am J Obstet Gynecol. 1954; 89:495–502.
Xiao L, Ding G, Vinturache A, et al. Associations of maternal pre-pregnancy body mass index and gestational weight gain with birth outcomes in Shanghai, China. Scientific Report. 2017;7:41073.