Maternal smoking and neonatal prostacyclin excretion.

To study the effect of smoking during pregnancy on the production of vasodilatory, antiaggregatory prostacyclin (PGI2) of the neonates, we measured the urinary excretion of 6-keto-prostaglandin F1a (6-keto-PGF1a, a metabolite of PGI2) on the first and on the third or fourth day of life of a group of babies of smoking (BSM, n = 14) and nonsmoking (BNSM, n = 13) mothers. The urinary excretion of 6-keto-PGF1a was similar in both groups (249.8 +/- 18.5, mean +/- SEM, and 262.7 +/- 35.0 pg 6-keto-PGF1a/mmol of creatinine for BSM and BNSM, respectively, on the first day of life; 109.4 +/- 18.6 and 133.3 +/- 18.5 pg/mmol for BSM and BNSM, respectively, on the third or fourth day of life). Thus smoking during pregnancy is not followed by such changes of PGI2 production that they were reflected by changes of urinary 6-keto-PGF1a of newborns on the first or on the third or fourth day of life.