RESUMEN
We surveyed 1, 312 pregnant women who were puerperal in-patients of this clinic by retrospective investigation for the effect of hot-spring bathing on the birth weights of babies they delivered.<br>The women were classified into eight groups.<br>Group 1 consisted of 14 pregnant women who took hot-spring baths every day and delivered male babies. Group 2 consisted of 115 pregnant women who took plain-water baths with additives every day and delivered male babies. Group 3 consisted of 139 pregnant women who took plain-water baths without additives every day and delivered male babies. Group 4 consisted of 16 pregnant women who took showers every day and delivered male babies. Group 5 consisted of 17 pregnant women who took hot-spring baths every day and delivered female babies. Group 6 consisted of 133 pregnant women who took plain-water baths with additives every day and delivered female babies. Group 7 consisted of 136 pregnant women who took plain-water baths without additives every day and delivered female babies. Group 8 consisted of 17 pregnant women who took showers every day and delivered female babies.<br>The weights of male babies were 3069.8±357.1g in group 1, 3139.3±396.0g in group 2, 3147.8±382.8g in group 3, and 3037.4±363.7g in group 4. The weights of female babies were 2966.2±337.9g g in group 5, 3050.7±390.6g in group 6, 3087.2±353.1g in group 7, and 3047.9±295.6g in group 8.<br>The weights of male babies were proportional to the duration of bathing. The weights of female babies were also proportional to the duration of bathing.<br>The weights of the placentas of male babies were not proportional to the duration of bathing. The weights of the placentas of female babies were proportional to the duration of bathing.<br>The ratio of the weights of male babies to the weights of the placentas was proportional to the duration of bathing. The ratio of the weights of female babies to the weights of the placentas was not proportional to the duration of bathing.<br>The conclusion: The above results demonstrate that pregnant women may take hot-springs baths without any adverse effect on the baby.