Population sciences

The Bangladesh population in 2008 is estimated at 145 million.

ICDDR,B has contributed to the success of the national family planning programme in Bangladesh by reducing fertility and the consequent growth rate. Our scientists have observed that the dramatic decline in fertility in Bangladesh (down from 6.5 children per woman in 1975 to 3.3 in 1994) has now levelled off. If fertility could be reduced to below replacement levels soon, the final population could be as much as 60 million fewer than otherwise. Further research is required to understand the apparent obstacles to further decline in fertility levels.

Given the large population in Bangladesh between the ages of 15 and 30, it is important that policies address the possible impact that this may have on population growth. For example, increased opportunities for young women to be educated and employed in the formal sector results in delayed marriage, and therefore delayed pregnancy - reducing overall fertility. This decline in fertility, while beneficial for slowing population growth, has other less desirable consequences. The elderly population will multiply almost ten-fold, from 6.8 million to 65 million, meaning that more than one in four people will be over the age of 60 years. The needs of the elderly will become increasingly important during the 21st century.

Arguably the major demographic phenomena of this century will be the massive increase in the numbers of urban poor. This global migration is driven by a search for employment. In rural areas urban migration will change the nature of nuclear families. There will be less family support available for the elderly left behind, an increase in sexually transmitted infections, and safety and security problems. In the cities it will accentuate infectious diseases, complicate provision of affordable health services and compound family instability, alienation, lawlessness and drug use.

At a glance

• Bangladesh’s population density is much higher than any other mega-country.
• In 2008, Bangladesh is only half way up the population growth curve and will reach more than 250 million later this century.
• Most of the increased population will be urban, and much of Bangladesh will essentially become a city state.
• The year that Bangladesh reaches replacement fertility is not as critical lowering fertility to less than replacement.
• The number of children born each year has now stabilized at slightly less 4 million.
• Age of marriage has not increased in Bangladesh as it has in other Asian countries.
• The elderly (>60 yrs) will grow in population from 7 to 65 million this century, and this will make many and different demands on the health system.
• There has been a major reduction in overall numbers of child deaths over the last three decades. Some of this reduction is due to reduced fertility and some is due to child survival interventions.

ICDDR,B has several large rural and urban demographically defined field sites. The population surveillance systems at these sites collect vital event data and provide a sampling frame for more intensive studies. Health interventions allow ICDDR,B scientists to determine burden of disease, test health interventions (e.g. micronutrients, vaccines, systems), and conduct social science research in order to understand the dynamics of population shifts. The longitudinal data collection systems at ICDDR,B are unique and are the basis on which other demographic systems are formed elsewhere in the world.