Fertility is one of the three principal components of population dynamics, the others being mortality
and migration (United Nations, 1973). Collection of data on fertility levels, trends and differentials
has remained a prime objective of the Demographic and Health Surveys (DHS) programme since its inception
in the 1980s. In Kenya, continued collection of such data through birth histories and other means
has been important in recognsing the important role that fertility plays in balancing Kenya’s overall population
growth equation. The fact that fertility reduction became the thrust of the country’s population policy
as early as 1967 underlines the deliberate efforts made by the Government to contain it.
The 2003 KDHS was conducted against the backdrop of a dramatic fertility transition that was
first reported in the 1989 KDHS. On the basis of the 1999 Kenya Population and Housing Census, fertility
was projected to continue to decline to a total fertility rate of 3.2 by 2015-2020 (Central Bureau of Statistics,
2002d: 27). The government and other stakeholders are therefore keen to monitor developments
with respect to the fertility transition process, with a view to evaluating the course of the fertility transition
through population and development policies and programmes.
This chapter presents an analysis of the fertility data collected in the 2003 KDHS. It includes a
discussion on levels, trends, and differentials in fertility by selected background characteristics; data on
lifetime fertility (children ever born and living); and a scrutiny of age at first birth and birth intervals.
Thereafter, a brief discussion on adolescent fertility, which has become critical to the issue of fertility
transition, particularly in the wake of a new policy modelled on adolescent reproductive health, is presented.

The fertility data were collected by asking all women of reproductive age (15-49 years) to provide
complete birth histories of all children they had given birth to, those who were currently living with
them, those who were living away, and those who had died. In addition, the following information was
collected for each live birth: name, sex, date of birth, survival status, current age (if alive), and age at
death (if dead). It is important to mention at the outset that the birth history approach has some limitations
that might distort fertility levels and patterns. For instance, women may include relatives’ children as their
own or omit children who died young, while older women may forget grown children who have left home
(United Nations, 1983). Accordingly, the results should be viewed with these caveats in mind.