Determinants of High Fertility Rate among Married Women in Ethiopia

Background: Fertility is one the major components of changing the population size and structure over time. Hence, this study aims to identify the socioeconomic and demographic factors associated with the high fertility rate among married women in Ethiopia Method: Ethiopian demography and health survey of 2016 data were accessed and used for the analysis. A total of 9602 married women were included in the study. Poisson regression models were employed by considering the number of children ever born (count) as a response variable. Results: A total of 9602 married women were included and 907 (9.4%) of the mothers have not born a child in their life time and only 307 (3.2%) of them have born more than 9 children. Rich women (IRR =0.794; 95%CI: 0.685, 0.920, secondary and above education of women (IRR =0.602; 95%CI: 0.570, 0.635), secondary and above education level of husbands’ (IRR =0.917; 95%CI: 0.880, 0.955) and late marriage (IRR =0.853; 95%CI: 0.832, 0.873) were found significantly associated with low level of fertility rate. Small family size (IRR =2.23.; 95%CI: 2.168, 2.294) and being child death experience (IRR =1.636; 95%CI: 1.601, 1.672) were also showed statistically significant association with high level of fertility rate. Conclusion: The government should focus on providing better access to education, increasing the coverage of family planning service and improving sources of income. Furthermore, the society should be made aware on consequences of high fertility on the child and maternal health, household economy, human capital investment and environmental degradation.


Introduction
Fertility is one the major components of changing the population size and structure over time. The world has experienced significant fertility declines over the past six decades. Total fertility at the global level fell from an average of 5 births per woman aged  year in 1950-1955 to 2.5 births per woman in 2010-2015. Among the world's regions, Africa remained the region with the highest fertility, averaging 4.7 births per woman in 2010-2015, with particularly high levels of fertility, on average 5.1 births per women, observed in sub-Saharan Africa [1,2].
From 2017 to 2050, it is expected that half of the world's population growth will be concentrated in just nine countries including Ethiopia. Ethiopia is currently the 12th most populous countries worldwide and the 2nd in Africa. The current population of Ethiopia is over 112 million. This is equivalent to 1.45% of the world population. The country is projected to be among the top eight countries in the world with the greatest population increase between 2017 and 2050, with the total population estimated to rise to over 190 million [3][4][5]. The fertility has been slightly declined in Ethiopia over time, from 4.8 children per woman in 2011 to 4.6 children per woman in 2016 [6][7][8].
Fertility is consistently higher among rural women, who give birth to nearly three more children during their reproductive years than urban women (5.2 versus 2.3 children per woman). Women in more remote and less developed regions give birth to more children than do women in the more developed regional states. The fertility rate is highest in Somali (7.2 children per woman) and lowest in Addis Ababa (1.8 children per woman)[3, 6].
The impact of high fertility rate has on health is reflected mainly in a rise in the rates of maternal and child mortality. In addition, Poverty, war and famine, weak infrastructure, and low agricultural and industrial production have exacerbated the problem of overpopulation [9,10]. So, understanding the factors responsible for the fertility level would help in designing strategies to effectively implement any program to tackle uncontrolled fertility. The common factors associated with fertility were (residence, wealth index, education of mother and father, working status mother, region, religion and age at first birth, use of contraception, family size and child death) [11][12][13][14][15]. However, previous studies in Ethiopia have done small geographical areas like regional level as well as district area and limited number of variables [12,13,[16][17][18][19][20][21][22][23]. Therefore, this study was aiming to identify the factors associated with high fertility among married women in Ethiopia.

Data sources
The data used for this study was taken from the 2016 EDHS which is a nationally representative survey of women's age (15-49 years age) groups taken from the Central Statistics Agency (CSA), Ethiopia. The survey is the fourth compressive survey designed to provide estimates for the health and demographic variables of interest for the whole urban and rural areas of Ethiopia as a domain. In all of the selected households, measurements were collected from children age 0-59 months, women age 15-49 years, and men age 15-59 years old.

Dependent Variable
The dependent variable in this study was the total number of children ever born per mother

Independent Variables
The independent variable were residence, wealth index, education level of mother, education level of father, occupation of mothers, region, religion age at first marriage, contraceptive use, family size and child death.

Data analysis
The data analyses were performed using R version 3.5.3 software. Descriptive statistics were used to explore the entire variables of the study. Poisson regression model have been used to determine the significant variables associated with high fertility rate. P-values of less than or equal to 0.05 were considered as statistically significant.

Trend of fertility from 2000 to 2016 in Ethiopia
The fertility rate has been slightly declined in Ethiopia over time.   (Table 1). Farther more, the average children ever born from mothers whose age at first marriage greater than 17 (2.96) is lower as compared to mothers whose age at first birth is less than or equal to 17(4.25).
The average children ever born were higher for mothers with no education (4.80) and not contraceptive use (4.04) among their respective groups (Table 2).

Factors associated with Fertility in Ethiopia
Here under factor associated with fertility were presented using Poisson regression model. Women who use contraceptives have significantly lower fertility rates than women who do not use (Table 3).

Discussion
The objective of this study was to identify socioeconomic and demographic determinants of high fertility in Ethiopia. According to the result, parental education level is an important socio-economic predictor of fertility, that is, fertility rate decreases with increase in parental education level. This result in lined with the previous study, the higher level of maternal and husbands education, the lower fertility [11,12,14,16,22,24,25].
The result reveled that there are clear regional variations of fertility levels in Ethiopia. Addis Ababa has very low fertility which is below replacement level of fertility. But, other regions like Somali, Oromiya and SNNP regions have high total fertility rates. This finding is coincide with other studies [25,26]. This may be due to different distribution and access of family planning services.
This study showed that the number of children from poor households was higher than children from rich households, and this is in agreement with other studies [11,15,25]. This may indicate that parents in poor households use children as a source of income. The findings also showed that women in rural areas have higher fertility rates than urban women. This is consistent with the study done in Ethiopia [12,16]. This result also consistent with the study done in Nigeria [11] and Bangladesh [14], which found that fertility rate is higher in rural areas. This may show that rural woman have a negative feelings towards smaller number of children and having little access to family planning as well as knowledge of using contraceptive method is low.
Age at first marriage has significant bearing on the number of children ever born alive. Those women who get married at early age leads to high fertility rate. This finding is coincide with other studies [12,22,24,27], which found that the incidence of fertility was low as increasing the age of marriage.
Participants who had never used contraceptive had more children as compared to their counterparts.
This is evidently clear that the aim of contraceptive method is to limit the number of children. Study conducted in Hwassa Town, Ethiopia [16] reported that use of contraception was statistically significant with low fertility. Other studies also reported women who were using contraception tended to have fewer children than those women not using a contraceptive [11,14,22,28].
The results of this study also show that the child death was found to have positive association with fertility. The fertility for women who had at least one child loss experience is higher than women who had no child loss experience. This finding is coincide with other studies [13,22]. Working status of a woman was believed to affect the number of children ever born. The results show that women who were working or employed had fewer children than that house wife. This is in line with [12,14,24], in which working mother is associated with lower fertility rates.
The study also revealed that household size is an important variable that affects the number of children ever born. Larger family size had higher fertility compared to those who belonged to smaller family size which is consistent with study in Butajira, Southern Ethiopia [13]. This might be due to when household member are large; they have enough time for their children to give care and expand.

Conclusion
The number of children ever born alive in Ethiopia is high. This study was revealed rural women, poor women, uneducated mother, uneducated husband, housewife mother, early married women, none contraceptive users, small family size and presence of child death were significantly associated with high fertility rate. Therefore, the government should focus on providing better access to education, increasing the coverage of family planning service and improving sources of income. Furthermore, the society should be made aware on consequences of high fertility on the child and maternal health, household economy, human capital investment and environmental degradation.

Limitations
Some variables are not included because of large number of missing values like age at first birth and sex preference. In addition to this, the interaction term is not considered under this study due to convergence issue.

Declarations
Authors' contribution SM analyzed the data and drafted the paper. SG revised subsequent draft of the paper. Both authors read and approved the final manuscript.