Chisholm et al. [4], using samples of Navajo and Malaysian newborns, found a significant positive relation between maternal normotensive blood pressures during the second trimester of pregnancy and at delivery and infant irritability in response to the Brazelton Examination. Measuring spontaneous crying with an electronic activity monitor and using a white middle-class American population, this relation was replicated for mothers with normotensive blood pressures during the third trimester of pregnancy. The combined findings of the 3 studies seem to suggest that maternal blood pressure in the latter part of pregnancy, even when within normal limits, is a factor in how irritable normal newborn infants are.