中国出生缺陷高发地区出生缺陷的发生水平和流行病学特征

目的研究中国出生缺陷高发地区出生缺陷的发生水平,分析主要出生缺陷的分布和流行病学特征。方法在出生缺陷高发的山西省选择2个高发县作为调查现场,对调查地区2002年1月1日至2004年12月31日期间孕满20周及以上的所有出生人口开展了以人群为基础的出生缺陷回顾性调查。结果调查地区2002—2004年出生缺陷发生率为844.2/万,发生率位于前五位的出生缺陷包括腹股沟疝(182.2/万)、无脑儿(104.4/万)、先天性智力低下(79.4/万)、先天性心脏病(73.2/万)和脊柱裂(63.9/万),前五位出生缺陷占全部出生缺陷的60%。国内外出生缺陷统计分析一般不包括腹股沟疝、鞘膜积液、隐睾和先天性智力低下,如果不包括这四类出生缺陷,调查地区出生缺陷发生率为537.2/万,位于前五位的出生缺陷分别为无脑儿、先天性心脏病、脊柱裂、脑积水(40.5/万)和脑膨出(31.2/万)。男性出生缺陷发生率为966.2/万,明显高于女性(640.4/万)。孕产妇年龄<20岁组和>30岁组出生缺陷发生率明显高于20～24岁和25～29岁年龄组。低龄孕妇发生神经管畸形和先天性心脏病的风险甚至显著高于高龄孕妇,孕产妇年龄<20岁组神经管畸形和先天性心脏病的发生率分别是408.8/万和188.7/万,而>30岁组两类出生缺陷的发生率分别为204.8/万和91.0/万。出生缺陷发生率随着孕产次的增加而明显提高。结论中国高发地区出生缺陷的发生呈现出与其他地区不同的流行病学特征,尤其是神经管畸形异常高发。不仅是高龄孕妇,20岁以下的低龄孕妇同样是一些出生缺陷发生的高危险因素。

Epidemiology of birth defects in high-prevalence areas of China

Objective To study the levels of prevalence and to describe the epidemiological features of birth defects in high-prevalence areas in China.Methods A population-based retrospective study was conducted in two counties of Shanxi province that including birth defects among fetuses and live births born after 20 weeks' gestational age in the study areas from 2002 through 2004.Results During 2002-2004, the prevalence of birth defects was 844.2 per 10 000 births in study areas and the first five main birth defects were inguinal hernia(182.2 per 10 000 births),anencephaly(104.4 per 10 000 births), congenital mental retardation(79.4 per 10 000 births),congenital heart diseases(73.2 per 10 000 births) and spina bifida(63.9 per 10 000 births).These five main birth defects accounted for about 60% of total birth defect cases.Inguinal hernia,undescended testicle,congenital mental retardation were usually not included for statistical analysis on birth defect.Excluding these birth defects,the prevalence of birth defects in study areas was 537.2 per 10 000 births and the first five main birth defects were anencephaly, congenital heart diseases,spina bifida,hydrocephaly(40.5 per 10 000 births)and encephalocele(31.2 per 10 000 births).The male prevalence of birth defects was 966.2 per 10 000 births,which was significantly higher than prevalence in females.The prevalence rates of birth defects for maternal age groups under 20 years old and over 30 years old were remarkably higher than those for 20-24 year and 25-29 year old mothers.The teenage mothers were at higher risk of having a child with neural tube defects(NTDs)or congenital heart diseases.Prevalence rates under 20 year maternal age group were 408.8 and 188.7 per 10 000 births for NTDs and congenital heart diseases respectively,whereas corresponding rates were 204.8 and 91.0 per 10 000 births for groups over 30 years of age.The prevalence rates increased with increasing gravidity or parity.Conclusion This study showed that the patterns of birth defects in study areas were very different from those of other areas,with an unusually high prevalence of NTDs.The study also suggested that both young and advanced mothers were at increased risk of having a child with a birth defect.