Contraceptive dynamics in Northeast Brazil

In a study of contraceptive discontinuation and switching women may contribute more than one spell of use interval to the sample and, therefore, spells of use from the same woman may be correlated. Moreover, it has been largely recognized that two stage sampling such as those used in the DHS are very likely to have hierarchical structures because individuals selected from the same cluster are more likely to have similar behaviour and attitudes in relation to contraceptive use than those selected from different clusters. Therefore, a series of multilevel models was used throughout this thesis, as they have been pointed out to be the most appropriate for data where observations are correlated.Four empirical studies are carried out in this thesis. First, we investigate factors associated with the choice of reversible methods and sterilization in the Northeast region. Second, the determinants of contraceptive discontinuation, including method failures are estimated. Next, a detailed analysis of contraceptive switching is focused. Finally, we undertake an analysis of the demand for contraceptives in the Northeast, in which the proportion of women with an unmet need for limiting or for spacing was estimated.In general, despite the increase in the level of contraceptive methods, the results show considerably high rates of discontinuation in the Northeast Brazil. Method related reasons, particularly side-effects play an important role in the decision to discontinue the use of a method. Method failure is also an important reason. Of particular concern are the higher rates of switching to no method. The findings suggest that the restrictive mix of contraception in the region constitutes a barrier for the efficient use of methods for spacing purposes, which might explain the fact that the need for contraception for limiting purposes has not declined during the period of study. The results also showed that education was the most important socioeconomic factor affecting choice, discontinuation, switching and consequently unmet need.