Smoking during pregnancy and lactation and its effects on breast-milk volume.

The influence of cigarette smoking on daily breast-milk volume was measured by the dose-to-mother deuterium-dilution method in 10 smoking and 10 nonsmoking mothers. After administration of deuterium to the mother, breast milk and infant saliva were sampled over 14 d and analyzed by mass spectrometry. Nonsmoking mothers had a significantly greater breast-milk volume than did smokers [961 +/- 120 vs 693 +/- 110 g/d, mean +/- SD; t = 5.21, P less than 0.0001). Growth rates of the infants were also measured. Weight increase of infants of non-smoking mothers was 550 +/- 130 g whereas of infants of smoking mothers it was only 340 +/- 170 g (t = 3.11, P less than 0.01). These results indicate that cigarette smoking has a negative influence on breast-milk volume whereas the lower infant-growth rates of the smoking mothers suggest also that their breast-milk output was insufficient to support the energy requirements of their infants.