Seasonal Variation in Spontaneous Abortions.

Abstract: Using a national sample of hospital discharges, we found identical seasonal patterns for spontaneous abortions and conceptions but no significant seasonal variation in the rate of spontaneous abortions per 1,000 conceptions. The difference between our findings and those of previous investigators of spontaneous abortion, our more complete estimate of the monthly number of conceptions, and our more rigorous statistical analysis. The periodic regression analysis. (PRA) reported in our study may be useful in other studies that monitor short-term trends. [ABSTRACT FROM AUTHOR]