Neveux L M, Palomaki G E, Larrivee D A, Knight G J, Haddow J E
Foundation for Blood Research, Scarborough, ME 04074, USA.
Prenat Diagn. 1996 Dec;16(12):1115-9. doi: 10.1002/(SICI)1097-0223(199612)16:12<1115::AID-PD3>3.0.CO;2-6.
This study examines the relationship between maternal weight and serum levels of alpha-fetoprotein, unconjugated oestriol, and human chorionic gonadotropin in a population of 47,585 women being provided with prenatal screening for Down's syndrome and open neural tube defects. The study population contains sufficient numbers of women at the extremes of weight to allow the determination that a reciprocal-linear equation more accurately describes the weight relationship for two of the three analytes than the currently used log-linear equations. The reciprocal-linear equations, while more appropriate, provide only a minimal advantage over the log-linear equations. A more important finding is that published weight equations may not be optimal for some screening programmes, due to differences in the mean weight of the populations being tested. Screening programmes are encouraged to calculate their own weight correction formulae, based on data from their own population, and to monitor the mean maternal weight to detect when modifications in the weight correction formulae might be indicated.
本研究调查了47585名接受唐氏综合征和开放性神经管缺陷产前筛查的女性群体中，孕妇体重与甲胎蛋白、非结合雌三醇和人绒毛膜促性腺激素血清水平之间的关系。研究群体包含足够数量体重处于极端水平的女性，从而能够确定，对于三种分析物中的两种而言，倒数线性方程比目前使用的对数线性方程能更准确地描述体重关系。虽然倒数线性方程更为合适，但相比对数线性方程仅具有极小的优势。一个更重要的发现是，由于受测群体平均体重存在差异，已发表的体重方程可能并非对所有筛查项目都是最优的。鼓励筛查项目根据自身群体的数据计算各自的体重校正公式，并监测孕妇平均体重，以发现何时可能需要对体重校正公式进行调整。
