Voiding pattern in healthy newborns

A 4-hour observation period has been used in infants to investigate suspect ed bladder dysfunction. The aim of the present study was to extend the usef ulness of this protocol by establishing reference values for voiding freque ncy, intervals, volumes, and residual urine in healthy newborns. The study included 51 healthy newborns, 26 girls and 25 boys, aged 3 to 14 days. Duri ng a 3-hour period. all micturitions and residuals were recorded as well as feeding, sleeping, crying, and defecations. The observation was completed with the child undressed to observe the urinary stream during one void. Dif ferent provocation tests were tried to induce urinary leakage. All newborns voided with a stream, about once per hour, with a median volume of 23 mL. For each voiding parameter, there was a large inter- and intra-individual v ariability. Double voidings were common as well as sizable residual volumes . The diuresis was about six rimes higher than in healthy school children. The healthy newborns did not leak during provocation tests such as manual c ompression of the bladder. (C) 2000 Wiley-Liss, Inc.