Woodman D D, Watson D, Hatch U
Ann Clin Biochem. 1978 May;15(3):157-60. doi: 10.1177/000456327801500134.
Amniotic fluid lecithin to sphingomyelin ratio (L/S) and adrenaline concentration, noradrenaline concentration, and noradrenaline to adrenaline ratio (NA/A) were measured in 50 normal women late in pregnancy. Between gestation weeks 37 and 43 the maturity-linked increase in L/S ratio was accompanied by similar increases in NA/A ratio and noradrenaline but by decreases in adrenaline concentration. Although the amniotic fluid NA/A ratio reflects fetal sympathetic nervous system development rather than pulmonary development as mirrored by the L/S ratio, a high correlation existed between log NA/A and L/S, indicating that the NA/A ratio could provide a further index of fetal maturity.
对50名妊娠晚期的正常女性测量了羊水卵磷脂与鞘磷脂比值（L/S）、肾上腺素浓度、去甲肾上腺素浓度以及去甲肾上腺素与肾上腺素比值（NA/A）。在妊娠第37至43周期间，与成熟度相关的L/S比值增加的同时，NA/A比值和去甲肾上腺素也有类似增加，但肾上腺素浓度降低。尽管羊水NA/A比值反映的是胎儿交感神经系统的发育，而非像L/S比值所反映的肺发育情况，但log NA/A与L/S之间存在高度相关性，这表明NA/A比值可为胎儿成熟度提供进一步的指标。
