The data collected by the National Institute of Population Studies, Islamabad in Pakistan Demographic and Health Survey, 1990-91 was analysed and investigated in this study. The data was in the computer base of the Institute consisting of 6,611 eligible women. The main emphasis of the data was on, background characteristics, reproductive history, knowledge and use of contraception, pregnancy and breast feeding, vaccinations and the health of children, marriages, family size preferences and husbands background. The main objective of this study was to, investigate statistical methods, which can be used, for the analysis of such data, so as to identify various variables that can affect the fertility pattern of the women using various types of contraceptive methods. This in turn will lead to identify variations among different methods of contraception that will have an effective control on the fertility of a "-Oman. For this purpose, different methods of analysis previously being used and recommended in the literature were studied and new methods were developed for analysis of this data so as to identify the variables of importance. Since the main purpose of the study was to investigate an association among the Fertility Behaviour in Women using different Methods of Contraception/fertility regulation methods. The initial part of the study contained an elementary data analysis of the data. This was done to find out the major sources of variation in the data, and to investigate the important variables affecting the fertility behaviour of the women. The current trend of rapid population growth in Pakistan calls for serious thinking and action. If it is allowed to continue with the prevailing growth rate, it will adversely effect the socio-economic development of tile country as with the current rate we are heading towards what is called population bomb. lf it explodes, it would devastate the economic and social fabric of our country. Hence, it is the time that these important variables effecting the fertility behaviour of a woman should be taken care off. In this study along with simple analysis of cross tabulation and summary statistics computed, regression analysis was also used. The method of regression analysis was used in two steps. First, simple regression models were analysed. Second, in order to see the effect of a variable on the dependent variable, new regression models were formulated and analysed. This method helped us in pinpointing the important variables and finally developing a model of choice. Further Analysis of Variance was used to see the overall significance of regression models. The important variables as identified in the present study were age of the respondent, education, living number of children, family planning practices and attitudes, spousal communication and husbands level of education etc. Finally one of the major conclusions derived from the present study was that there was a strong association among the fertility behavior of the women using various contraceptive methods and hence its effects on the number of children born. Besides this, the study indicated that modern contraceptive methods are more effective as compared to traditional methods.