Savva George M, Morris Joan K, Mutton David E, Alberman Eva
Centre for Environmental and Preventive Medicine, Wolfson Institute of Preventive Medicine, Barts and The London School of Medicine and Dentistry, UK.
Prenat Diagn. 2006 Jun;26(6):499-504. doi: 10.1002/pd.1443.
Pregnancies affected by Down syndrome (DS) have a greater risk of spontaneous fetal loss than those that are unaffected. In this article, we investigate the relationship between maternal age and the risk of spontaneous fetal loss in DS pregnancies.
Fetal loss at different maternal ages were estimated by survival analysis using follow-up of 5177 prenatally diagnosed cases. The maternal age effect on loss rate was subsequently confirmed by a re-analysis of published comparisons of the maternal age-specific prevalence of DS at different gestational ages.
The average fetal loss rate between the time of chorionic villus sampling (CVS) and term was 32% (95% CI: 26-38), increasing from 23% (95% CI: 16-31) for women aged 25 to 44% (33-56) for women aged 45. The average fetal loss rate between the time of amniocentesis and term was 25% (21-31), increasing from 19% (14-27) to 33% (26-45) across the same age range.
The fetal loss rate in DS pregnancies increases with maternal age, and this has consequences when estimating the live birth prevalence of DS in the presence of prenatal diagnosis and termination, and when assessing the performance of prenatal screening techniques.
与未受影响的妊娠相比，受唐氏综合征（DS）影响的妊娠发生自然流产的风险更高。在本文中，我们研究了母亲年龄与DS妊娠中自然流产风险之间的关系。
通过对5177例产前诊断病例的随访，采用生存分析估计不同母亲年龄的胎儿丢失情况。随后，通过重新分析已发表的不同孕周母亲年龄特异性DS患病率的比较结果，证实了母亲年龄对丢失率的影响。
绒毛取样（CVS）至足月期间的平均胎儿丢失率为32%（95%CI：26 - 38），25岁女性为23%（95%CI：16 - 31），45岁女性则增至44%（33 - 56）。羊膜穿刺术至足月期间的平均胎儿丢失率为25%（21 - 31），在相同年龄范围内从19%（14 - 27）增至33%（26 - 45）。
DS妊娠中的胎儿丢失率随母亲年龄增加而升高，这在估计存在产前诊断和终止妊娠情况下DS的活产患病率以及评估产前筛查技术的性能时会产生影响。
