The primary objective of this research is to examine the effects of pregnancy loss on birthspacing patterns in women of Matlab Thana, Bangladesh. Special attention will be paid to how the risk of pregnancy loss varies among women, the effects of maternal age on the risk of loss, and the stage of gestation at which loss occurs. A sample of 375 women will be monitored over an eleven-month period, and urine samples will be collected from them twice a week. The study will use new, highly sensitive assays of urinary chorionic gonadotropin, which allow detection of pregnancy within a few days of conception. These assays will permit the first community-wide study of early pregnancy loss ever to be conducted. It is necessary to carry out this research in a developing country because, in western women, the relevant patterns are obscured by family planning. This research is of theoretical importance in elucidating the factors that determine reproductive rates under conditions of natural fertility. It is also of clinical importance in developing methods for the identification of women at high risk of pregnancy loss, and in counseling older women who wish to become pregnant.
