Adolescent birth rate
The adolescent birth rate (ABR) is defined as the annual number of births in women aged 15–19 years old per 1000 women in the same respective age group (1). The adolescent birth rate is also referred to as the age-specific fertility rate (ASFR) for women aged 15–19 years old.
The four main data sources for this indicator are:
- Civil registration and vital statistics (CRVS) systems
- Routinely collected administrative data
- Population-based household surveys
- Nationally representative census data
Civil registration and vital statistics systems
A well-functioning and integrated national or subnational CRVS system will universally register and certify vital events, including live births, stillbirths and deaths that occur in the country or administrative area. Birth and death certificates should be issued as part of the CRVS system, allowing the compilation, analysis and dissemination of information through vital statistics agencies, including population characteristics (e.g. sex, date of birth/death, place of birth/death, place of usual residence) and cause-of-death information. Some CRVS systems will also register and certify other important vital events within the population, such as adoptions, marriages and divorces (2).
Data from CRVS are the preferred data source for this indicator when the system freely and universally records vital events and data are recorded in a systematic manner that ensures high data quality for both the public and private health sectors, regardless of birth location (e.g. health facility or community-based birth).
Key source of data: The main source of data from this indicator involves several steps and will vary based on the policies and procedures of the national or subnational CRVS or other routine system within health facilities and/or communities. Declaration of the live birth and age of mother can be obtained through: (a) forms completed by health personnel at health facilities; or (b) community-based sources, including registration forms submitted directly by the parents of the live birth and/or death. Either paper or electronic forms containing this information are then submitted to the relevant civil authorities and/or vital statistics agencies, which have the responsibility to officially record the birth event and issue information on birth and/or death characteristics such as name, date and place of birth, nationality, and names and ages of the mother and/or father. At the national or subnational level, the civil authority or vital statistics agency formalizes the birth and registration. National or subnational civil authorities or vital statistics agencies are responsible for reporting live birth information specific to this indicator.
Indicator calculation: The indicator is calculated as the number of live births to women aged 15−19 years per 1000 women aged 15–19 during a specified time period. The calculation is as follows:
(The number of women aged 15–19 years with a live birth in a specified period / Total number of women aged 15–19 years old [per 1000] in a specified time period)
To compute the rate per 1000 births, the numerator is divided by the denominator and multiplied by 1000. In order to calculate the denominator, estimates of exposure to childbearing by women aged 15–19 years old (per 1000 women) in the population is necessary, either through census data or other representative sources.
Frequency of measurement: Within CRVS, this indicator is generally monitored at a national or subnational level on an annual basis. The data can be compiled and aggregated subnationally to provide national-level data.
Disaggregation: By maternal age, sex, place of birth, place of residence (e.g., urban, rural), subnational administrative units (e.g., districts, provinces, regions) and type of reporting source (e.g., health facility, community).
Missing values: Missing values are usually not known. To ascertain missing data, estimates of the total number of live births to women aged 15–19 years old in a country or administrative area can be compared with the absolute number of live births in the same period.
Routinely collected administrative data
Data from routinely collected and compiled administrative data sources will provide information as recorded in medical charts/records or registers and are entered into national and/or subnational health management information systems (HMIS).
Data from health information systems may collect information on the ABR among live births in a health facility. Routinely collected administrative data and health facility statistics are the preferred data source in settings without an established CRVS system and when there is high utilization of health facility services and data are recorded in a manner that ensures good data quality for both the public and private health sectors. The compiled data in the national HMIS or District Health Information System (DHIS2) should include data from both the public and private health sectors, especially when the private sector is a substantial source of service provision to the population. In settings where utilization of health facilities is not high (e.g., settings with a high prevalence of births occurring at home), data may suffer from incompleteness if information about women delivering outside facilities is not captured. In addition, there are often challenges in accurately measuring the numerator and the denominator when routine health information system data are used to measure this indicator.
Key source of data: Administrative data sources include health facility and health services data abstracted from obstetric and neonatal medical records, including health service registers. Relevant information is recorded about live births, date of birth and maternal age for deliveries occurring at health facilities on paper forms completed by health personnel and/or through an electronic medical record. Data from paper or electronic sources are ideally entered or abstracted into a database or registry and are compiled and analyzed within the national and/or subnational HMIS. The ministry of health (MoH) and/or national statistical offices (NSO) are usually responsible for the reporting of this indicator.
Indicator calculation: The indicator is calculated as the number of live births to women aged 15−19 years in health facilities per 1000 women in the same age group during a specified time period. The indicator calculation is as follows:
(Number of live births to women [aged 15−19 years] in health facilities during a specified time period / Total number of women [aged 15–19 years] during a specified time period)
To compute the rate per 1000 births, the numerator is divided by the denominator and multiplied by 1000. In order to calculate the denominator, estimates of number of women aged 15–19 years old in the population is necessary either through census data or other representative sources.
Frequency of measurement: The indicator can be calculated on an annual basis or may be tracked on a more frequent and ongoing basis (e.g., monthly, quarterly), depending on facility, subnational and national processes for data entry, compilation and analysis. As a guide, the recommended frequency of measurement based on reporting level is outlined below:
- Facility level: Monthly, quarterly, or as needed based on the country and/or facility need
- Subnational level (first and second administrative level): Monthly or quarterly
- National level: Annually (data can be aggregated to provide national-level data).
Disaggregation: By maternal age, sex, place of birth, place of residence (e.g., urban, rural), subnational administrative units (e.g., districts, provinces, regions) and level of facility.
Missing values: Missing values are usually not known or not reported.
Population-based household surveys
The main source of data for this indicator has been through population-based household surveys collected through nationally or subnationally representative and structured questionnaires, such as:
- Demographic Health Surveys (DHS) (3)
- Multiple Indicator Cluster Surveys (MICS) (4)
- Reproductive Health Surveys (RHS)
- Other household surveys.
Population-based household survey data are the preferred data source in settings without an established CRVS system and utilization of health facility services is not very high (e.g., settings with a high prevalence of births occurring at home) or where private health sector data are excluded from routinely collected administrative data sources.
Key source of data: Eligible women of reproductive age (15–49 years) are identified in the household survey for inclusion and interviewing using an individual women’s questionnaire. Women are considered eligible for survey interview if they are either usual residents or visitors of the household who stayed there the night before the interview.
Calculations for this indicator are based on having the interviewer complete a full birth history, whereby eligible women are asked to report the names and relevant information for all live births they have had in their lifetime. In some instances, a shortened birth history may be implemented in the survey in order to calculate the list of all live births during a specified time period, usually five years prior to the date of the survey interview. The birth history does not include stillbirths, miscarriages, or abortions. For each of the children the woman has given birth to, they are asked to record in chronological order from first to last birth: the sex (male or female), multiple births (singleton or multiple), the date of birth (day, month, and year) and whether the child is currently alive (yes or no) and if no longer alive, the age at death in days, months, or years.
The MoH and NSO typically conduct household surveys and compile, analyze and report the results for this indicator in collaboration with the survey program (e.g. DHS, or other survey) and funding agency.
Indicator calculation: Individual women of reproductive age (15–49 years old) are asked about the total number of live births they have had in their lifetime or during a specified time period prior to survey interview.
The ABR is the number of live births to women aged 15−19 years (per 1000 women) in that age group. The indicator is calculated as follows:
(Number of interviewed women aged 15–49 years with a live birth in the two [or five] years prior to survey completion / Total number of interviewed women aged 15–19 years old in the two [or five] years prior to survey completion)
To compute the rate per 1000 births, the numerator is divided by the denominator and multiplied by 1000.
Frequency of measurement: Household surveys are typically conducted every 3–5 years.
Disaggregation at population level: Socioeconomic status (e.g., education level, household wealth quintile), age of woman at the time of interview, place of residence (e.g. urban, rural), subnational administrative units (e.g., districts, provinces, regions), total number of living children at the time of interview, total number of antenatal care (ANC) visits, and timing of first ANC.
Missing values: Missing values are not allowed for any of the variables that make up the rate. In particular, the date of interview and the age of the woman would be key for calculation of this indicator.
Information from nationally representative censuses will provide information on ABR for the entire population in the 12 months preceding the enumeration. In some cases, the rates based on censuses are adjusted for under-registration based on indirect methods of estimation. The ABR is generally computed on the basis of the date of last birth or the number of births in the 12 months preceding the enumeration period.
Indicator calculation: The indicator is calculated as follows:
(Number of registered live births born to females aged 15–19 during a given year / Estimated or enumerated population of females aged 15–19 years in a given year)
Frequency of measurement: The indicator can be calculated on an annual basis. National censuses are completed every 5–10 years.
Disaggregation at population level: Age, education level, marital status, number of living children, place of residence, socioeconomic status.
Missing values: Missing values are either not known or not reported.
An estimated 295 000 women died from pregnancy or childbirth-related complications in 2017. Adolescent girls are at a higher risk of morbidity and mortality due to complications in pregnancy, when compared to women of older ages (5). Reducing adolescent fertility and addressing the multiple factors underlying it are essential for improving sexual and reproductive health as well as the social and economic well-being of adolescents. Preventing births very early in a woman’s life is an important measure to improving maternal health and reducing infant mortality.
The ABR represents the risk of childbearing among females in the particular age groups. It is commonly reported as the age-specific fertility rate for ages 15–19 years in the context of calculation of total fertility estimates. It has also been called the adolescent fertility rate. This indicator can be used to inform health system planning and policy and the allocation of funds and resources for programs and interventions aimed at improved maternal, newborn and child health and survival.
Discrepancies between the sources of data at the country level are common and the level of ABR depends in part on the source of the data selected. Thus, the quality of reporting this indicator varies greatly between and within countries, particularly in countries without effective civil registration systems in place. Many countries lack a single source of high-quality data covering the last several decades. Data from different sources require different calculation methods and may suffer from different errors – for example, random errors in sample surveys or systematic errors due to misreporting. As a result, different sources often yield different estimates of the ABR at a given time period and available data collected by countries are often inconsistent across sources.
Civil registration and vital statistics systems
Birth registration should be part of a national and/or subnational CRVS system. However, CRVS systems are either non-existent and/or the complete coverage, accuracy and timeliness of civil registration systems is a major issue in many countries worldwide. In order to assess the completeness of the CRVS system, evaluations should be conducted to ascertain the quality of the system, as recommended by the United Nation’s revised Principles and Recommendations for a Vital Statistics System (2).
As a result, it is common for live births to be unregistered, particularly for stillbirths and neonatal deaths occurring shortly after birth. This may be due to lack of a legal framework within civil authorities or vital statistics agencies requiring registration for all births, regardless of the outcome. Even in countries with functional CRVS systems and legal frameworks in place, missing or unregistered births still occur due to health professionals and/or parents not knowing the requirement of the need to register stillbirths or in the instance of neonatal death, both the live birth in addition to the death. It is also common for maternal age not to be recorded as part of the birth registration, rendering indicator calculations impossible.
Data collected from administrative and other routine data systems
Administrative data may suffer from poor quality, such as irregularities in report generation, data duplication and inconsistencies (6). Reporting challenges exist at the facility level given data quality issues, including incomplete, inaccurate and lack of timely data due to insufficient capacity in the health system or inadequate system design.
Many HMIS databases or registries are event-based and only births that occur in health facilities are included. Administrative data should be interpreted with caution in settings where data quality is poor and the percentage of births at public and private sector health facilities is low, or where data from the private health sector is not compiled within the HMIS reporting.
In settings where routine HMIS data lack information on pregnancies and/or births or deliveries that occur outside the public sector – for example, in homes, in the community, or in private sector facilities – the total number of births in the HMIS should not serve to estimate the denominator for this indicator. Where data on the total number of live births for the entire population for the denominator are unavailable, evaluators can calculate total estimated live births using census data for the total population and crude birth rates in a specified area (total expected live births = estimated population x the total crude birth rate).
Data collected through household surveys
The systematic recording of live births, stillbirths and deaths in many countries remains a serious challenge. In the absence of reliable CRVS systems/administrative data, household surveys have recently become the source of data to monitor levels and trends of stillbirths. In many low- and middle-income countries, such surveys represent the sole source of this information. For survey and census data, both the numerator and denominator come from the same population. The main limitations are related to age misreporting, birth omissions and misreporting the date of birth of the child, as well as sampling variability (7).
For more information on this indicator, please see the MoNITOR indicator reference sheet developed by the World Health Organization: Who-indicators (srhr.org).
family planning, adolescent, safe motherhood (SM)
About 14 million women and girls between ages 15 and 19 (both married and unmarried) give birth each year and the leading cause of death for women aged 15–19 years old is related to pregnancy or childbirth complications, with unsafe abortion being a major factor (5,8). Adolescent mothers are more likely to have children with low birth weight, inadequate nutrition and anemia, and these young women are more likely to develop cervical cancer later in life. Moreover, early childbearing is linked to obstetric fistula, a devastating and socially isolating condition that can leave women incontinent, disabled, and in chronic pain. Globally, early childbearing often results for women in higher total fertility, lost development opportunities, limited life options, and poorer health.
- Global reference list of 100 core health indicators (plus health-related SDGs). Geneva: World Health Organization; 2018 (https://apps.who.int/iris/bitstream/handle/10665/259951/WHO-HIS-IER-GPM-2018.1-eng.pdf), accessed 21 October 2020.
- Principles and recommendations for a vital statistics system. Revision 3. New York: United Nations; 2014 (https://unstats.un.org/unsd/demographic/standmeth/principles/M19Rev3en.pdf), accessed 21 October 2020.
- The DHS Program [website]. Rockville: ICF International; 2020 (http://www.dhsprogram.com/ ), accessed 21 October 2020.
- Multiple Indicator Cluster Surveys (MICS) [website]. New York: UNICEF; 2020 (http://mics.unicef.org), accessed 21 October 2020.
- Abouzahr C, Boerma T. Health information systems: the foundations of public health. Bull World Health Organ. 2005;83(8): 578–83.
- World population prospects: 2017 Revision: methodology of the United Nations Population Estimates and Projections. New York: United Nations; 2017 (https://esa.un.org/unpd/wpp/Publications/Files/WPP2017_Methodology.pdf) accessed 21 October 2020.
- Trends in maternal mortality 2000 to 2017: estimates by WHO, UNICEF, UNFPA, World Bank Group and the United Nations Population Division. Geneva: World Health Organization; 2019.
- UNFPA, 2005, ‘The Promise of Gender Equality: Gender Equity, Reproductive Health and the MDGs’, State of the World Population 2005, New York; UNFPA. (http://www.unfpa.org/swp/2005/english/indicators/index.htm).