Monthly cosmic activity and pregnancy induced hypertension.

Monthly distribution of PIH (Pregnancy Induced Hypertension) was investigated in relation to the number of deliveries and nine specific cosmic and geomagnetic activity parameters during the years 1979-1983. PIH was observed in 3.165% of 19,843 deliveries. Significant (p less than 0.01) inverse correlation between the PIH index and monthly geomagnetic activity level was shown. Moderately significant (p less than 0.05) correlation with monthly maximal (noon hours) gamma-radiowave propagation was evident as was inverse correlation with this parameter in hours of minimal (early morning) propagation.