TRENDS AND FACTORS AFFECTING THE INTERVAL FROM MARRIAGE TO FIRST BIRTH AMONG WOMEN OF REPRODUCTIVE AGE IN NIGERIA

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D.M. Moradeyo, J.O. Akinyemi, O.B.Yusuf

Department of Epidemiology and Medical Statistics, Faculty of Public Health, University of Ibadan.

Abstract

Background: The shorter the time interval between marriage and first birth, the sooner subsequent pregnancies are likely to occur in the absence of contraceptives and family planning. This can have negative impacts on the mother, children and society. This study explores the trend in the time between marriage and the first birth among Nigerian women.

Materials and Method: Kaplan-Meier’s estimation and multilevel survival models were used to analyze data from the Nigeria Demographic and Health Survey (NDHS) records from 1990, 2003, 2008 and 2013. The study focused on women who entered marriage without children or pregnancy. The surveys employed a two-stage cluster sampling method. Variables extracted included birth cohort, age at sexual initiation, age at first marriage, age at first birth, educational level, religion, place of residence, knowledge of contraceptive
and ovulatory cycle.

Results: The results indicated that the median time to first birth after marriage decreased from 2 years to 1 year. Significant factors associated with a higher likelihood of having first birth shortly after marriage included having primary education (HR = 1.17; CI=1.14-1.21), knowledge of contraceptives (HR= 1.21; CI =1.20-1.26, ovulation cycle (HR=1.21, CI=1.18-1.25), marriage above 19 years (HR = 1.19, CI=1.15-1.25), women residing in South east (HR= 1.17, CI =1.10- 1.22), South West (HR = 1.30, C.I=1.24-1.37) and community influence (p=1.37, ICC = 0.06).

Conclusion: The reduced time to first birth after marriage underscores the need for policy-makers to promote higher level education and family planning among women of reproductive age in Nigeria.

Keywords: First Marriage, Fecundity, Time to first birth, Multilevel Survival models.

Introduction

The birth of the first child is the foremost visible outcome of being fertile and it serves as an event of great social and individual significance. First birth marks a woman’s transition into motherhood.^1,2,3 The birth of the first child plays an important role in the future of a woman and has a direct relationship with the nation’s fertility.⁴ The expectation of most women, and especially married couples, is to have children, the longer they stay without having children the more frustrated they become.⁵

The waiting time to first birth after marriage is defined as the interval between the time a couple is wedded, whether legally, socially or traditionally and the arrival of their first child. In sub-Saharan Africa, marriage without children is incomplete, and family members of the couple expect the first birth within a short period after marriage to prove the couple’s fecundity, especially the wife. In addition, the birth of the first child is also proof of the husband’s fertility.⁶ Previous studies have shown that the time to first birth after marriage can affect the survival and happiness of a marriage.^7,5 Society and parents’ pressure on the bride to have her first birth and subsequent childbirth is difficult to resist in developing countries.⁸ Therefore, to ensure sustainability of a marriage, signs of pregnancy and birth of the first child is expected from the bride within the first year of marriage.⁵

Though the occurrence of first birth within a short period after marriage is expected to bring joy and happiness, it also has negative impact on the women and population of a country. The earlier the arrival of the first baby in a marriage the earlier the subsequent pregnancy in the absence of contraceptive use and family planning.⁵ Sub-Saharan Africa is burdened by high rates of unintended pregnancies and only 22%of married women are currently using contraceptives.⁹ Sub-Saharan Africa has the lowest contraceptive prevalence and highest level of unmet need for contraception of all world regions. Nigeria, with a contraceptive prevalence rate of 13-15% is not exempted.¹⁰ If it happens that an undesirable pregnancy occurs after the first baby it can lead to unsafe or illegal abortion. Otherwise the risk of bearing many children after first birth cannot be ruled out in the absence of contraceptives.

The waiting time to first birth after marriage is either stable or decreasing in the previous studies reviewed. A study by Amin & Barjrachanya¹¹ stated that in the countries where median age at first marriage is under 17 years, the median time to first birth after marriage is consistently higher than 2 years (24 months). Other studies which estimated the median time to first birth after first marriage to be about 2 years were carried out in Uganda and Ghana.^12,5

A decrease in time from 36 months for older cohorts to 27 months for the younger cohorts was found in a study on age at first marriage and first birth interval in Ethiopia by Gurmu and Etana.¹³ The decline in time to first birth after marriage among the younger marriage cohorts was attributed to the signal of response to policy and programmatic interventions which prohibit marriage before age 18. Similar to this is a study to assess age at marriage and the first birth interval among young Chinese couples, the long waiting to first birth after marriage decreased from around 34 months in the 1950s to less than 18 months in the 1980s. ¹⁴ This was attributed to the Chinese government’s family planning programme which is believed to have caused a rise in age at marriage and restricting fertility. In order to compensate for late start, couples tend to bear their first child soon after marriage.

Age at first marriage was found to be one of the significant predictors of bearing a child after first marriage.^{15,16,17,13,18,12} It was discovered that women who marry below 20 years of age have a lower chance of having their first children early compared to women who marry at a slightly older ages (20 to 31 years). In contrast, age at first marriage, either younger age or older age was not a predicting factor of transition time to first birth after marriage in a study carried out by Anuwoje and Albert⁵ in Ghana.

There were chances of having the first child earlier after marriage in rural areas compared to urban areas.^13,19 However Anuwoje and Albert⁵ showed that the place of residence, whether rural or urban, has no significant effect on the time to first birth after marriage. Educational attainment of a woman has no significant effect on her time to first birth after marriage.^5,12 In some other studies, education was a significant predictor of time to first birth. Women with higher levels of education were found to have a shorter waiting time to first birth after marriage.^20,13,4

The chance of having a first child after marriage was found to be associated with the knowledge of ovulation cycle.¹² Women who are conscious of their ovulation cycles have a higher chance of having their first children early compared to those that are ignorant of their ovulation cycles. Also, women who have access to reproductive information on radio, television and newspapers have a higher chance of having their first children earlier than those without access to reproductive health information.¹⁹

Women who initiate sex at early ages have a slightly higher chance of experiencing their first births more quickly after marriage compared to women who started sex at later ages.^21,12 Anuwoje and Albert⁵ showed that age at first intercourse has no significant effect on transition time to first birth after marriage.

Previous studies in Nigeria have investigated time and factors affecting age at first marriage and first birth ^22,23,24,25 but the waiting time between marriage and first birth has scarcely been analyzed. Understanding of waiting time between marriage and first birth is of direct relevance to health planners and policymakers attempting to control population variables and enforce or promote safe motherhood.^{26, 23} This study will shed more light on the need to increase efforts on improvement of access to effective contraceptive methods, family planning in Nigeria. The purpose of this study is to determine transition time to first birth after marriage and the factors associated with it.