Magann Everett F, Chauhan Suneet P, Doherty Dorota A, Lutgendorf Monica A, Magann Marcia I, Morrison John C
Department of Obstetrics and Gynecology, Naval Medical Center Portsmouth, Portsmouth, VA, USA.
Obstet Gynecol Surv. 2007 Dec;62(12):795-802. doi: 10.1097/01.ogx.0000290349.58707.e0.
Idiopathic hydramnios is defined as hydramnios that is not associated with congenital anomalies of the central nervous system or gastrointestinal tract, maternal diabetes, isoimmunizaton, fetal infection (CMV or toxoplasmosis), placental tumors, or multiple gestations. Hydramnios is diagnosed when the AFI is > or = 24 or > or = 25 (> or = 95 or > or = 97.5%), the single deepest pocket (SDP) as being > or = 8, or the examiner's subjective assessment of having an increased amount of amniotic fluid volume. The prevalence of hydramnios is 1%-2% with 50%-60% of those cases as being idiopathic. A PUBMED search from 1950 to 2007 and Science Citation search from 2001 to 2007 revealed only 3 studies that compared pregnancies with idiopathic hydramnios to pregnancies without hydramnios, and 4 studies that evaluated perinatal mortality with hydramnios after correcting for congenital anomalies. Idiopathic hydramnios was found in the larger studies to be linked to fetal macrosomia, an increase in the risk of adverse pregnancy outcomes, and a 2- to 5-fold increase in the risk of perinatal mortality. Tests that may be helpful in the antenatal evaluation of these at-risk pregnancies are: Doppler flow velocimetry of the middle cerebral artery, nonstress test, biophysical profile, and contraction stress test. Prospective studies are needed in this area that is understudied where risk of an adverse pregnancy outcome and perinatal mortality are increased.
Obstetricians & Gynecologists, Family Physicians.
After completion of this article, the reader should be able to state the prevalence of idiopathic hydramnios, recall the lack of data relating to outcome, explain that there is a 2- to 5-fold increase in the risk of perinatal mortality, and summarize the lack of consensus in monitoring pregnancies afflicted with idiopathic hydramnios.
特发性羊水过多定义为与中枢神经系统或胃肠道先天性异常、母体糖尿病、血型不合、胎儿感染（巨细胞病毒或弓形虫病）、胎盘肿瘤或多胎妊娠无关的羊水过多。当羊水指数（AFI）≥24或≥25（≥95或≥97.5%）、单个最深羊水池（SDP）≥8，或检查者主观评估羊水过多时，可诊断为羊水过多。羊水过多的患病率为1%-2%，其中50%-60%为特发性。对1950年至2007年的PubMed搜索以及2001年至2007年的科学引文搜索显示，仅有3项研究比较了特发性羊水过多妊娠与无羊水过多妊娠，4项研究在纠正先天性异常后评估了羊水过多时的围产期死亡率。在规模较大的研究中发现，特发性羊水过多与胎儿巨大儿、不良妊娠结局风险增加以及围产期死亡率增加2至5倍有关。对这些高危妊娠进行产前评估可能有用的检查包括：大脑中动脉多普勒血流速度测定、无应激试验、生物物理评分和宫缩应激试验。在这个研究不足、不良妊娠结局和围产期死亡率风险增加的领域，需要进行前瞻性研究。
妇产科医生、家庭医生。
阅读本文后，读者应能够说出特发性羊水过多的患病率，回忆与结局相关的数据缺乏情况，解释围产期死亡率风险增加2至5倍，总结在监测特发性羊水过多妊娠方面缺乏共识。
