Warren C W, Gold J, Tyler C W, Smith J C, Paris A L
Am J Public Health. 1980 Dec;70(12):1297-9. doi: 10.2105/ajph.70.12.1297.
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 differences between our findings and those of previous investigators of spontaneous abortion may reflect our more comprehensive definition 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.
通过对全国医院出院病例的抽样调查,我们发现自然流产和受孕存在相同的季节性模式,但每1000次受孕的自然流产率没有显著的季节性变化。我们的研究结果与先前自然流产研究者的结果之间的差异,可能反映了我们对自然流产的定义更为全面、对每月受孕数量的估计更为完整,以及我们的统计分析更为严格。我们研究中报告的周期性回归分析(PRA)可能对其他监测短期趋势的研究有用。