The 1972 Population Census indicates that the population of Pakistan is growing at a rate of about 3% per year. The 1975 Pakistan Fertility Survey (PFS) is probably the most reliable collection of data and was conducted by the Population Planning Division as part of the World Fertility Survey. Examination of the data shows that the birth histories of the recent past do not have serious omissions or misplacement of births. In earlier censuses older women tended to omit or misplace births, particularly female births. Infant mortality rates are consistent with the expected trend of gradual improvement over time. Within age cohorts some tendency was noted for older women to omit children dying before age 1. No specific over or under reporting is shown for marriage age. The urban age at marriage is about 1-1 1/2 years older than the rural age. 1975 figures show the average age at first birth for 5-year marriage cohorts as follows: for age 20-4, average 20.2 years; for age 25-9, average 19.9 years; for age 30-4, average 19.3 years; for age 35-9, average 19.3 years; for age 40-4, average 18.3 years; and, for age 45-9, average 18.8 years. The infant mortality rates for both sexes from 1945-73 averaged 154/1000.

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