Fig. 6From: The suprachiasmatic nucleus: age-related decline in biological rhythmsInteractions between circadian rhythms and the estrous cycle. A scheme for age-related decline in biological rhythms. Stable circadian rhythms are essential for regular estrous cycles (a). Age-related declines in circadian output of the SCN and environmental perturbations of LD cycles may be potential risk factors for irregular estrous cycles and resultant infertilities (b)Back to article page