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ORIGINAL ARTICLE |
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Year : 2019 | Volume
: 16
| Issue : 2 | Page : 103-108 |
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Maternal predictors of blood transfusion among neonates in the Neonatal Intensive Care Unit of Ahmadu Bello University Teaching Hospital Zaria, Nigeria
Ibrahim Usman Kusfa1, Aisha Indo Mamman1, Mohammed Sani Shehu2, Isa Abdulkadir3, Ismaila Nda Ibrahim1, Aliyu Dahiru Waziri1, Sani Awwalu1, Aisha Maude Suleiman1, Haruna Mohammed Muktar1, Tukur Dahiru4
1 Department of Haematology and Blood Transfusion, Ahmadu Bello University Teaching Hospital, Zaria, Nigeria 2 Department of Histopathology, Ahmadu Bello University Teaching Hospital, Zaria, Nigeria 3 Department of Paediatrics, Ahmadu Bello University Teaching Hospital, Zaria, Nigeria 4 Department of Community Medicine, Ahmadu Bello University Teaching Hospital, Zaria, Nigeria
Date of Submission | 10-Jul-2019 |
Date of Decision | 11-Sep-2019 |
Date of Acceptance | 07-Oct-2019 |
Date of Web Publication | 19-Nov-2019 |
Correspondence Address: Dr. Ibrahim Usman Kusfa Department of Haematology and Blood Transfusion, Ahmadu Bello University Teaching Hospital, Zaria Nigeria
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/njbcs.njbcs_18_19
Background: Maternal health and healthcare accessibility are important determinants of neonatal survival. Pregnancy-related complications may lead to maternal anemia and, maternal micronutrient deficiency, conditions which could result in neonatal anemia necessitating transfusion. Objectives: To determine maternal predictors of neonatal blood transfusion. Methods: We conducted a case–control study on mother–infant pairs of cases and controls. A semi-structured questionnaire was used to collect information. Logistic regression was used on maternal predictors, and the level of significance was set at ≤0.05. Results: The overall mean (±standard deviation) age of mothers in both case and control groups was 21.79 ± 10.71 years, respectively. The likelihood of neonatal transfusion was increased by parity of ≥5 [odds ratio (OR): 3.1, 95% confidence interval (CI) = 1.26–7.39], while age of ≥18 years at first marriage, attainment of at least secondary school, four antenatal care (ANC) visits before delivery, birth interval of ≥2 years, and hematinics use during pregnancy were associated with reduced neonatal blood transfusion (OR: 0.36, 95% CI = 0.14–0.96), (OR: 0.66, 95% CI = 0.32–1.37), (OR: 0.70, 95% CI = 0.25–1.99), (OR: 0.55, 95% CI = 0.19–1.62), and (OR: 0.63, 95% CI = 0.17–2.36), respectively. Conclusion: We found that high parity, teenage mothers, inadequate ANC visits, short birth interval, and hematinics noncompliance during pregnancy were all associated with increased need of blood transfusion among neonates.
Keywords: Anemia, blood transfusion, maternal predictors, neonatal intensive care unit
How to cite this article: Kusfa IU, Mamman AI, Shehu MS, Abdulkadir I, Ibrahim IN, Waziri AD, Awwalu S, Suleiman AM, Muktar HM, Dahiru T. Maternal predictors of blood transfusion among neonates in the Neonatal Intensive Care Unit of Ahmadu Bello University Teaching Hospital Zaria, Nigeria. Niger J Basic Clin Sci 2019;16:103-8 |
How to cite this URL: Kusfa IU, Mamman AI, Shehu MS, Abdulkadir I, Ibrahim IN, Waziri AD, Awwalu S, Suleiman AM, Muktar HM, Dahiru T. Maternal predictors of blood transfusion among neonates in the Neonatal Intensive Care Unit of Ahmadu Bello University Teaching Hospital Zaria, Nigeria. Niger J Basic Clin Sci [serial online] 2019 [cited 2019 Dec 8];16:103-8. Available from: http://www.njbcs.net/text.asp?2019/16/2/103/271120 |
Introduction | |  |
Maternal health and healthcare accessibility are important determinants of neonatal survival.[1],[2] Some pregnancy-related complications may lead to maternal anemia, and maternal micronutrient deficiency resulting commonly from maternal depletion syndrome remains a major cause of maternal anemia leading to high transfusion demand in both the mother and the newborn.[3] Complications during labor are important determinants of fetal and neonatal survival and health. Some of these complications are common causes of neonatal anemia leading to transfusion in the neonate.[4] Maternal interventions such as iron supplement, folic acid, and vitamin B12 during pregnancy undoubtedly positively influence pregnancy outcome particularly in relation to newborn survival.[5]
Anemia is a common problem in children in parts of Asia, Central South America, and sub-Saharan Africa which in severe cases is treated with blood transfusion.[6] Studies have shown that more than 50% of all hospitalized pediatric patients in sub-Saharan Africa received blood transfusions for severe anemia during their admission.[6]
Neonatal transfusion burden varies among centres and units. Multiple transfusions are common among preterm and even sick-term neonates admitted into neonatal intensive care units (NICUs) and such transfusions usually entail small volume or component transfusion. There is generally a low rate of voluntary blood donation in Nigeria and couple with absence of blood components' separation facilities. These make neonatal blood transfusion challenging and straining to the health systems. Defining maternal correlates which could determine and predict neonatal anemia could be a starting point toward planning to prevent neonatal anemia and by extension neonatal blood transfusion. This study, therefore, aimed at studying maternal predictors of blood transfusion among neonates in Zaria, North-Western Nigeria.
Methods | |  |
Study settings
This study was conducted in the NICU of Paediatrics Department of Ahmadu Bello University Teaching Hospital (ABUTH), Zaria. The unit has a total number of 32 beds with an average of 22 neonatal admissions requiring blood transfusion per month.
Study design
We conducted a case–control study on 60 each of mother–infant pairs of cases and controls, respectively. A semi-structured, interviewer-administered questionnaire was used to collect information from all mothers who consented to the study. The following maternal predictor variables were collated: age at first marriage, occupational status, educational level, average number of antenatal care (ANC) visits before delivery, place of initial care during pregnancy, duration of labor, parity, birth interval (BI), use of insecticide-treated mosquito nets (ITNs), and use of hematinics during pregnancy.
Study population
Cases were defined as mother–infant pairs in which the neonates (newborns age 0–28 days) were admitted into the NICU for various indications and required at least one type of blood transfusion. Conversely, controls were mother–infant pairs whose neonates did not require blood transfusion despite being admitted in the NICU. We excluded mothers with multiple gestations.
Sampling technique
The respondents were selected consecutively using convenient sampling technique.
Study instruments
A semi-structured interviewer-administered questionnaire was used. The first section contains questions on sociodemographic data: age, age at first marriage, occupation, level of education, marital status, religion, tribe, and so on. The second section contains questions on reproductive profiles: parity, average number of ANC visits before delivery, BI, use of hematinics during pregnancy, place of initial care during pregnancy, duration of labor, use of ITNs, and during pregnancy.
Data collection
Each questionnaire was administered by an interviewer who was trained for the purpose. Ethical conduct guiding a research such as respecting the autonomy of the participants and confidentiality were upheld. Data collection took place from February to May 2017.
Data management
The questionnaires were examined for completeness and accuracy. The data were subsequently entered into an electronic database using Microsoft excel version 2010 for Windows. Tables were used to show frequencies and proportions on maternal sociodemographic variables and predictors.
Sample size determination
The minimum sample size was determined using the formula for two groups. The prevalence of blood transfusion among neonates from a previous study was 27.9% in South-Western Nigeria.[7] The level of error of 5% and confidence interval (CI) of 95% were assumed, giving a sample size of 60 each of mother–infant pairs of cases and controls after correcting for nonresponse rate of 10%.
Statistical analysis
The data were analyzed using Epi Info version 7 (CDC, Atlanta, GA, USA). Univariate analysis was carried out by computing frequencies and proportions. Multivariate (logistic regression) analysis was used to determine the associations between these maternal predictors between the two groups. Maternal predictors were the independent variables, while neonatal blood transfusion was the dependent variable. The level of statistical significant relationship was set at or less than 5% (P ≤ 0.05).
Ethical approval
Ethical approval was obtained to conduct the research from the Ahmadu Bello University Teaching Hospital Health Research Ethic Committee (HREC) after submission of the study protocol. Participation of the mothers in this research was voluntary, and they were also told of their freedom to withdraw from the study at any point. A written informed consent was obtained from the literate participants, while nonliterate participants thumb-printed the consent form.
Results | |  |
The mean (±standard deviation) age, age at first marriage, and packed cell volume of mothers in both case and control groups were 26.51 ± 6.79 versus 27.58 ± 6.13 years, 20.48 ± 4.93 versus 20.34 ± 4.04 years, and 27.70 ± 11.90 versus 32.90 ± 4.03%, respectively [Table 1]. The median ages with interquartile range of all the neonates in both the case and control groups were 2.5 (27) and 3.0 (20) days, respectively, with 71 (59.2%) of the neonates being males. The likelihood of neonatal transfusion was increased by parity of ≥5 [odds ratio (OR): 3.1, 95% CI = 1.26–7.39)], while age of ≥18 years at first marriage, attainment of at least secondary school, four ANC visits before delivery, BI of ≥2 years, and hematinics use during pregnancy were associated with reduced neonatal blood transfusion (OR: 0.36, 95% CI = 0.14–0.96), (OR: 0.66, 95% CI = 0.32–1.37), (OR: 0.70, 95% CI = 0.25–1.99), (OR: 0.55, 95% CI = 0.19–1.62), and (OR: 0.63, 95% CI = 0.17–2.36), respectively [Table 2]. | Table 2: Multivariate analysis of maternal factors associated with blood transfusion in neonates
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Discussion | |  |
This study has shown that neonates born to mothers age 18 years and above at first marriage were less likely to be transfused. The United States Agency for International Development (USAID) facilitated study by Finlay et al.[8] showed that age at first marriage of ≥18 years improves delivery and neonatal outcomes by attainment of maximal maternal physical and cognitive development. Therefore, delaying pregnancy until at least a healthy age of 18 years may improve their own growth and development and also reduces the risks of poor nutritional outcomes for their infants. In the same study, Finlay et al. stated that a 32% increase in the risk of moderate to severe anemia has been linked to neonates born to mothers below 18 years. However, in the Nigeria Demographic Health Survey (NDHS 2013), the median age at first marriage was found to be 18.1 years.[9] The majority of mothers in this study married at the age of 18 years and above, which is similar to the NDHS report. Women who marry early will, on average, may have longer exposure to pregnancy and a greater number of lifetime births.[9]
The low rate of employment in this study contrasts with the NDHS report where 79% of women were self-employed and engaged in sales and services.[9] The absence of a significant relationship between occupational status of mothers and neonatal transfusion in this study suggests that mothers' occupation does not have an influence on neonatal blood transfusion. The difference between the two studies may be due to the large sample size used by the NDHS. Also, the differences in spousal awareness and family support systems may be important factors.
The majority of the respondents in this study had at least secondary education. This study showed that mothers who at least attained secondary education were less likely to have neonates requiring blood transfusion. A 2013 Demographic Health Survey (DHS) from three different sub-Saharan African countries indicates that increased maternal education is a strong determinant of child health and nutrition which is similar to the findings in this study.[10] Another in Nairobi by Abuya et al.[11] reported similar associations between maternal education and child health. Better educated mothers are more likely to maintain their own nutritional status, which can potentially reduce the risk of poor birth outcomes in the future.
The majority of mothers in this study had at least four ANC visits before delivery. This is in line with the World Health Organization (WHO) recommendations. Hence, the Maternal and Neonatal Health (MNH) initiative advocates a minimum of four antenatal visits before delivery.[12] Similar study by the NDHS showed that the majority (61%) of women had received ANC from a skilled healthcare provider nationally.[9] However, in the same study, North-West zone has only 41% of women who had ANC from a skilled healthcare provider. Our study revealed that neonates whose mothers had at least four ANC visits are less likely to be transfused than those whose mothers had less. The major objective of the focused ANC visits is to ensure optimal health outcomes for the mother and her baby.
Although not statistically significant between neonatal blood transfusion and the place of initial ANC, mothers who went to hospital as the place of first care during pregnancy were less likely to have their neonates transfused. This may be because the mothers were attended to by skilled healthcare providers in these hospitals. In addition, higher educational levels of these mothers might have impact in choosing the right place for their care.
Prolonged labor is an important cause of maternal and perinatal mortality and morbidity and is a risk for uterine rupture, operative deliveries, sepsis, hemolysis, anemia, and resultant need for blood transfusion.[13] Duration of labor in this study shows a nonsignificant association with neonatal transfusion status. The average duration of labor beyond which intervention is considered for both primiparous and multiparous women is 12 h. However, those mothers who experienced at least 12 h and above during labor are 1.5 times more likely to have their neonates transfused compared with those mothers who experienced less.
Our finding on parity in this study indicates that mothers who delivered five times and above are three times more likely to have their neonates transfused compared with those mothers who delivered four times or less. In a study by Winkvist et al.,[3] high parity may be attributed to nutritional stresses on successive pregnancies and lactation resulting in anemia, inadequate pregnancy weight gain, and low infant weight. Kozuki et al.[14] revealed that women with high parity of three and above had increased odds of preterm birth compared with women with parity of one or two. Interestingly, a transcontinental study revealed that compared with parity 3 women, parity 6 women had significantly lower coverage of key maternal and child health services.[15] The authors suggest that this may provide a partial explanation for adverse pregnancy outcomes associated with high parity births. Another independent study by Kozuki et al.[16] suggests that the apparent relationship between parity and poor birth outcomes may in fact be entirely due to confounding. This means that the link between parity and adverse birth outcomes is not clearly understood which may be due to mother's level of completed fertility. Different studies by Reinhardt,[17] Omran and Standley,[18] and Prentice et al.[19] in Abidjan, Geneva, and Gambia, respectively, have instead either found an association between high parity and improved nutritional status or no association at all. They suggested that parity may not be an accurate indicator of reproductive stress and parity does not provide information about miscarriages, abortions, or still births, and the spacing of pregnancies as well as the length of breastfeeding. Again if women of poor health are unable to bear more children, high parity women may include only the healthiest individuals.[20]
Our finding suggests that a BI length of at least 2 years has a protective effect on the neonatal blood transfusion. Twenty-four months is the minimum period recommended by the WHO between the birth of one child and conception of another.[21] The impact of adequate birth spacing on the survival and nutritional status of infants has been well-established by Rutstein,[22] Conde-Agudelo et al.,[23] and Wendt et al.[24] Additionally, the NDHS[9] demonstrated that children born too soon after a previous birth, especially if the interval between the births is less than 2 years, have an increased risk of sickness and death at an early age. The exact causal mechanisms have not been fully validated, but one common theory is maternal depletion, whereby women experience a negative change in nutritional status due to mobilization of nutritional reserves during pregnancy and lactation.[3] Short BI also places mother at risk of nutritional anemias and other micronutrient deficiencies and this may lead to poor birth outcome.[25] Therefore, optimally spaced pregnancies allow the mother's body to adequately recuperate and replete these reserves.[26]
The use of ITNs by the mothers in this study did not show any significant association with neonatal blood transfusion. The use of ITNs as one of the core vector-control interventions has made a major contribution to the reduction in malaria burden since the year 2000.[27] It has been shown that repeated or severe malaria infection in pregnancy may lead to maternal anemia, low birth weight, and perinatal mortality.[28],[29],[30] Therefore, the difference between the finding in this study and that of the WHO may be due to the sample size.
The majority of mothers in this study took iron and folic acid tablets mostly as routine drugs throughout pregnancy. The use of iron and folic acid during pregnancy has been shown to be protective against neonatal blood transfusion. The marginal advantage conferred by the use of hematinics is probably due to poor compliance. This is in keeping with the NDHS[9] report where the majority of respondents took iron tablets or syrup during pregnancy. Our finding of higher use of iron and folic acid during pregnancy is similar to reports from Ethiopia and Sudan by Shewasinad and Negash,[31] and Abdullahi et al.,[32] respectively. However, a lower rates have been previously reported in Nigeria,[33] Tanzania,[34] and Kenya.[35] The reason for the high uptake of iron and folic acid in this study may be because the study was carried out in a tertiary hospital, and the results may not necessarily be representative of practice in some communities or rural areas due to regional differences. Thus, successful uptake of iron-folic acid supplementation is linked to the use of ANC during pregnancy.[36] The use of hematinics is part of a comprehensive package to ensure maternal and under-5 survival.
Conclusion | |  |
High parity, teenage mothers, inadequate ANC visits, short BIs, and noncompliance with hematinics during pregnancy were all associated with increased risks of neonatal blood transfusion.
Recommendations
In patrilineal societies like Zaria, male involvement (as fathers, spouses, religious, and community leaders) results in improved girl-child education, attendance at ANC clinic, and adherence to hematinic usage. Male support in girl-child education facilitates adoption of key actions for health promotion (KAHP).
Acknowledgements
The authors thank the entire staff of Neonatal Intensive Care Unit of ABUTH, Zaria, for their support and cooperation during the course of data collection. They also thank all their supervisors and colleagues for going through the work and making it possible. They would also like to thank the management of ABUTH, Zaria, for giving the ethical approval for the research.
Financial support and sponsorship
Nigeria Field Epidemiology and Laboratory Training Programme (NFELTP).
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2]
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