O'Donoghue Keelin, Giorgi Laura, Pontello Valentina, Pasquini Lucia, Kumar Sailesh
Centre for Fetal Care, Queen Charlotte's and Chelsea Hospital, London.
Prenat Diagn. 2007 Nov;27(11):1000-4. doi: 10.1002/pd.1820.
Amniocentesis in the third trimester, which reduces risks of procedure-related miscarriage but still allows termination of affected fetuses, may be applicable in some pregnancies. The implications of deferring amniocentesis include complications, delivery before the test and increased amniotic fluid culture failure rates. We investigated the indications, complications, karyotype results and laboratory failure rates of third-trimester amniocentesis.
We studied all women who underwent third-trimester amniocentesis from 2000 to 2006. Data were collected from ultrasound databases, computerised records and individual chart review.
We reviewed 165 pregnancies that underwent amniocenteses after 28 weeks. Median maternal age at amniocentesis was 32 years and median gestation, 32(+2) weeks. Indications included malformation (60/165), soft markers (37/165), maternal request (12/165), and positive screening test (11/165). Of the 49 women(29.7%) who declined second-trimester amniocentesis, 24.5% had twins and 38.8%, malformations. Amniocentesis was not offered to 116 women: 57/116 (49.1%) third-trimester referrals, 25/116 (21.5%) diagnosed late and the remainder, low-risk indications. Fetal karyotype was abnormal in 17 cases (10.3%). Seven women who initially declined amniocentesis had abnormal results compared with one advised to have late amniocentesis. Culture failure rate was 9.7%, however results were obtained by Quantitative fluorescent polymerase chain reaction (QF-PCR) from 164/165 samples. Complication rate was 1.2%.
For late diagnoses and for low-risk indications, third-trimester amniocentesis is an acceptable option, especially when utilising QF-PCR with cytogenetic culture.
孕晚期羊膜腔穿刺术可降低与操作相关的流产风险，但仍能让受影响胎儿终止妊娠，在某些妊娠中可能适用。推迟羊膜腔穿刺术的影响包括并发症、检查前分娩以及羊水培养失败率增加。我们研究了孕晚期羊膜腔穿刺术的指征、并发症、核型结果及实验室失败率。
我们研究了2000年至2006年期间接受孕晚期羊膜腔穿刺术的所有女性。数据从超声数据库、计算机记录及个人病历审查中收集。
我们回顾了165例孕28周后接受羊膜腔穿刺术的妊娠。羊膜腔穿刺时孕妇的中位年龄为32岁，中位孕周为32（+2）周。指征包括畸形（60/165）、软指标（37/165）、孕妇要求（12/165）及筛查试验阳性（11/165）。在49例（29.7%）拒绝孕中期羊膜腔穿刺术的女性中，24.5%怀有双胞胎，38.8%存在畸形。116例女性未接受羊膜腔穿刺术：57/116（49.1%）为孕晚期转诊，25/116（21.5%）诊断较晚，其余为低风险指征。17例（10.3%）胎儿核型异常。7例最初拒绝羊膜腔穿刺术的女性结果异常，而建议进行晚期羊膜腔穿刺术的女性中有1例结果异常。培养失败率为9.7%，不过通过定量荧光聚合酶链反应（QF-PCR）从164/165个样本中获得了结果。并发症发生率为1.2%。
对于晚期诊断及低风险指征，孕晚期羊膜腔穿刺术是一个可接受的选择，尤其是在将QF-PCR与细胞遗传学培养结合使用时。
