The World Health Organization (WHO) describes an adolescent as any individual between ages 10 and 19. In this sense, adolescent pregnancy can be defined as the occurrence of pregnancy in female children aged 10 to 19. In this post, we would focus more on the birth rates among adolescents aged 15–19 years, as that is the range for which data is widely available.


Each year, over 20 million girls (15 to 19 years) in developing countries become pregnant and an estimated 12 million of them give birth (Darroch et al., 2016). No less than 770,000 births occur to adolescent girls below the age of 15 years in developing countries (UNFPA, 2013). Adolescent pregnancy has become a major public health problem, particularly in sub-Saharan Africa where almost 10% of girls become mothers by age 16 years, leaving them with the highest rates in Africa. Consequently, the region is also known for the high rate of maternal and child morbidity, and mortality.

Figure 1: Distribution of Adolescent birth rate across Nigeria, NDHS  2018. (Source: The MSDAT)

According to the Nigerian Demographic Health Survey (NDHS), the adolescent birth rate in 2018 was 106 births per 1,000 women. Bauchi state had the highest number of adolescent births (198), while Imo state had the least (Fig. 1). Generally, adolescent births seem to be higher in the North, specifically in the North-Western Zone (Fig. 2) where the median age of first marriage and first intercourse is approximately 16 years (NDHS, 2018).

Figure 2: Adolescent birth rate across geopolitical zones NDHS, 2018 (Source: The MSDAT)

Figure 3: Adolescent birth rate in the country over the years NDHS, 2018 (Source: The MSDAT)

The rate of adolescent births in Nigeria has steadily declined since the year 2003, from 126 to 106 births per 1,000 adolescent girls (Fig. 3), the 2018 value is the lowest since 1990.

Data shows that the average age of first sexual intercourse is roughly within the 15 years of age bracket among adolescent mothers in Nigeria (DHS 2003; 2008; 2013). Teenage pregnancy is known as a major contributor to the number of school dropouts. In a research carried out by AntwiDanso and Edet in 2011, results showed that the majority of girls dropped out of school as a result of pregnancy and some became pregnant as early as primary six of the Nigerian school system.

Figure 4: Percentage of 15-19 year olds who have either given birth or are pregnant with their first child (WHO, 2018) 

The figure above shows the percentage of 15-19 year old girls who have either given birth or are pregnant with their first child from the year 1990 to 2015. In 2015, there was a 9% increase in the percentage of girls who had given birth, and there was a 0.7% increase for the percentage of girls who were pregnant with their first child. This chart shows a steady increase in the number of both girls who had given birth before and who was pregnant with their first child. The percentage of women aged 15-19 years who had given birth previously significantly outweighed the percentage of those pregnant with their first child and has remained on an increase.

Figure 5: Leading causes of girls’ death (WHO, 2018)

Fig 5. depicts the number of deaths and the death rate per 100,000 girls. Maternal conditions were listed as the third highest cause of death among girls in Nigeria, with a total of 6,202 deaths (i.e. about 31% deaths per 100,000 girls). This was much higher than deaths resulting from meningitis and sickle cell disease.


Adolescent pregnancies mostly occur in low and middle-income countries, commonly influenced by poverty and lack of education among others (UNICEF, 2013). In a number of communities, young girls are pressured to marry and give birth early (WHO, 2020; Kozuki et al., 2013). According to the World Bank, over 36% of girls in underdeveloped countries marry before the age of 18, and 12% before the age of 15.

Misconceptions about the use of contraceptives, and the inability to access them due to age, marital status or financial constraints, are also determinants of the age at which first pregnancy can occur (WHO, 2011). Another major contributing factor is sexual violence as 1 out of 3 girls in some communities reported their first sexual encounter as coerced (Raj & Boehmer, 2013).


Early pregnancies among adolescents have major health consequences for adolescent mothers and their babies. Pregnancy and childbirth complications are the leading cause of death among girls aged 15–19 years. 

1. Without adequate support from their parents, adolescents are at risk of not getting antenatal care. Antenatal care is critical in the first months of pregnancy, as it looks for medical problems in both mother and baby, monitors the baby’s growth, and helps to quickly identify any complications that arise. While there is no risk-free pregnancy, a  good antenatal care and support can help minimize those risks. 

2. Factors like age and overall health status can increase the chances of experiencing complications during pregnancy (Joham, et al., 2014). Adolescents are at a higher risk for pregnancy-related high blood pressure (preeclampsia) and its complications than average age mothers. Preeclampsia can also harm the kidneys or even be fatal for mother or baby. Mothers aged 10–19 years face higher risks of eclampsia, puerperal endometritis and systemic infections than women aged 20–24 years. Pregnant teens have a higher risk of getting a pregnancy-induced hypertension — than pregnant women in their 20s or 30s. 

3. Pregnant adolescents also have a higher chance of becoming anemic. Anemia is a reduction in the number of red blood cells. This can make mothers feel weak and tired and can affect the baby’s development.

4. Adolescents are at a higher risk of having premature babies that weigh less than babies normally should (low-birth-weight). In addition, the earlier a baby is born, the more risk there is of respiratory, digestive, vision, cognitive, and other problems. Low birth-weight babies are also 5–30 times more likely to die than babies of normal weight. 

5. If a mother is under 18, her baby’s chance of dying in the first year of life is 60 percent higher than that of a baby born to a mother older than 19 (UNICEF, 1994).

6. For Adolescents who have sex during pregnancy, Sexually Transmitted Diseases (STDs) such as chlamydia and HIV are a major concern. Part of this heavy toll has more to do with poor socio-economic status and lack of ante-natal and obstetric care than physical maturity alone. 

7. Additionally, millions of unsafe abortions among girls aged 15–19 years occur each year, contributing to maternal mortality, morbidity and lasting health problems.


Social consequences for unmarried pregnant adolescents may include stigma, rejection or violence by partners, parents and peers. Girls who become pregnant before the age of 18 years are more likely to experience violence within a marriage or partnership. Adolescent pregnancy and childbearing often leads girls to drop out of school, thereby jeopardizing their future education and employment opportunities (WHO, 2020). 


At the decision-making point of their lives, youths are susceptible to sexual abuse and coercion which are just a few factors affecting adolescent pregnancy. 

Adolescent pregnancy and motherhood have implications for several different aspects of primary health care. First, the provision of health education and contraceptive services is very relevant to the prevention of unplanned pregnancy. Secondly, appropriate obstetric care should be provided for teenagers, who are at high risk of developing complications in pregnancy and childbirth. 

According to the CDC, girls who feel down and sad, either while pregnant or after birth, who can’t tell their parents they’re pregnant, or are feeling scared, isolated, and alone can eventually fall into depression. In the absence of proper support from the family or other adults, pregnant adolescents are less likely to eat well, exercise, or get plenty of rest. Having at least one trusted, supportive adult or someone nearby in the community, if not a family member — is invaluable in helping them get the antenatal care and emotional support they need to stay healthy during this time.


The implementation of interventions to inform and empower young girls; and the increase in educational opportunities for girls can help delay the age of marriage among girls under 18 years of age. Through education, interventions that combine curriculum-based sexuality education and the use of contraceptive education to adolescents is recommended. It would help reduce pregnancy rates in adolescents and improve the health service delivery to them as a means of facilitating their access to, and use of contraceptive information/services that will in turn reduce the rates of adolescent pregnancy.


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