Soyka L F, Neese A L, Main D, Main E
Semin Perinatol. 1981 Oct;5(4):332-6.
About 50% of 327 umbilical cord sera from infants born at the Medical Center Hospital of Vermont contained 1.0 microgram/ml or more of caffeine; about 25% contained equivalent concentrations of theophylline. Cord concentrations of caffeine greater than 3.0 micrograms/ml were associated with a significantly increased incidence of birthweights greater than 4 kg and a decrease in the incidence of 1-minute Apgar scores of less than seven. Cord blood caffeine concentrations of 69 infants born in Marburg, West Germany had a mean of 1.6 micrograms/ml, with 64% greater than 1 microgram/ml. Caffeine accumulated in the serum of infants treated with aminophylline for apnea of prematurity, apparently from methylation of theophylline.
佛蒙特医学中心医院出生的327名婴儿的脐带血清中，约50%含有1.0微克/毫升或更高浓度的咖啡因；约25%含有同等浓度的茶碱。脐带中咖啡因浓度高于3.0微克/毫升与出生体重超过4千克的发生率显著增加以及1分钟阿氏评分低于7分的发生率降低有关。在西德马尔堡出生的69名婴儿的脐带血咖啡因浓度平均为1.6微克/毫升，其中64%高于1微克/毫升。接受氨茶碱治疗早产儿呼吸暂停的婴儿血清中会积累咖啡因，显然是由茶碱甲基化产生的。
