Reproductive patterns among Swedish women born 1936-1960.

An analysis was made of a cross-sectional survey of 4,299 women born in Sweden in the period 1936-1960, regarding their reproductive performance. Fecundability was only 12% lower for women in the 30-39 year age interval than for women up to 29 years of age. Cumulative pregnancy rates for individual years fell in the range 93-96%. No difference in fecundability could be discerned between women born in 1936-45 vis-à-vis 1946-60. Primary and secondary infertility were noted for 6.6% and 11.0% respectively of the entire population surveyed. Primary infertility, more prevalent among those born in 1946-60, was found to be related to a higher level of education, an urban life style and low age at first coitus. The risk of suffering a spontaneous abortion increased with advancing maternal age.