|especially to the fear of their supposed side effects and to the lack of true knowledge. The persistence of cultural barriers to the use of these methods stems from the socio-cultural patterns of female sexuality in the lower classes. These patterns include misinformation about and devaluation of woman's sexuality, woman's submission to her father and spouse, the impossibility of woman's control of her own reproductive life, and the inability to foresee the consequences of having a large family.|
During this century Peru has held four population censuses, in 1940, 1961, 1972, and 1981. For the female population aged 12 years and over, the first two censuses gathered only past information about fertility: children ever born. To estimate the TFR, this information had to be combined with the births recorded in the vital register (an average of those births occurring in 1939, 1940, and 1941 for 1940, and in 1960, 1961, and 1962 for 1961). The two latter censuses compiled, in addition to the total number of children born, those born in the preceding year, making it possible to estimate the TFR indirectly (utilizing Brass's P/F method) on the basis of the census data only. In spite of their obvious limitations, the censuses are the fundamental basis for knowledge of fertility's evolution in Peru during the period 1940-60, for which no other sources are available. The combination of data from diverse sources completes the picture for more recent dates, and also allows the projection of the evolution's future behaviour.
The Peruvian register of births is affected by, among others, two limitations: (1) a considerable, but variable, percentage of omission, and (2) a delay in the publication of the reports. These defects and others, like the quality of data, determine that registered births, classified by the age of the mother, cannot be used to calculate direct estimates of fertility.
Sample surveys are an indispensable complement to the demographic information gathered in Peruvian censuses and registers. These have been carried out quite frequently since the end of the 1960s and have made it possible to clear up doubts, fill gaps and explain certain aspects of the demographic patterns at the national and regional level. Between 1966 and 1968, the Rural Urban Fertility Survey (PEAL-PECFAL) took place, with a sample of 4,676 women of fertile age, for which (as far as fertility data are concerned) a full pregnancy history was recorded. Between 1974 and 1976, the National Demographic Survey (NDS) was held; using a prospective format or repeated visits, in which a representative sample of 48,000 persons of whom 10,672 were women of fertile age were surveyed. During the last round of visits ( 1976), a Retrospective Survey (RETRO) was applied, gathering information on live-born children and children born in the preceding year from all the women of fertile age registered in the NDS. Between 1977 and 1978, the National Fertility Survey (NFS) was held, with a sample of 5,640 ever-in-union women aged 15 to 49 years whose pregnancy history was recorded. The National Survey of Contraceptive