The data on cryptorchidism in the Danish National Patient Registry are quite accurate. In etiological research the limited misclassification will in most cases only slightly attenuate estimates of the true relative association. Thus, the registry has the potential to serve as a valuable research tool, although caution should be exercised when studying time trends or geographical differences.

Lubricant use during intercourse was not associated with time to pregnancy in a study of pregnancy planners.

Background: Fluid balance monitoring is commonly used to assess patient fluid volume status. However, studies on its reliability and usefulness are lacking, particularly in newborns.