Objective: To determine if higher fertility and lower contraceptive use among the poorer segments of society should be considered an inequality, reflecting a higher desire for large families among the poor, or an inequity, a product of the poor being prevented from achieving their desired fertility to the same degree as wealthier segments of society. 

Methods: Using the most recent Demographic and Health Surveys from 41 countries, we analysed the differences in fertility in light of modern contraceptive use, unwanted fertility (defined as actual fertility in excess of desired fertility) and the availability of family planning services found among poorer and wealthier segments of society. The asset index in each survey was used to construct wealth quintiles and the concentration index (CI) of income inequality was found in health variables.

Findings: The relationship between the CI found in the total fertility rate and the use of contraceptives was linear, R-square of 0.289. Unwanted births in the poorest quintile were more than twice that found in the wealthiest quintile, respectively 1.2 and 0.5, although there was wide variation among the 41 countries. The CI in our measure of family planning availability (radio messages, knowledge of services and contact with field workers) was largely positively associated with the CI in modern contraceptive prevalence, respectively R-squares of 0.392, 0.692 and 0.526.

Conclusion: In many countries the higher fertility and lower contraceptive use found among poorer relative to wealthier populations should be considered an inequity.