However, specifically in urban areas, the predominant factors that contributed to the fertility decline that occurred between 1997 and 2002 were, in order of magnitude, an increase in induced abortion, duration of postpartum infecundability and postponement of marriages. During the same period, the leading factors responsible for the fertility decline in rural areas, in order of magnitude, were postponement of marriages, increase in induced abortion and contraceptive use. Among women living in rural areas, the declining role of post-partum infecundability is of concern if it is not compensated by increased use of effective family planning methods.