脑动静脉畸形（AVM）破裂出血已知的危险因素有既往出血，深静脉引流和部位深等。而妊娠一直以来是神经外科医生假定的一个重要危险因素，近期发表在《神经外科学》支持这一推测。该研究表明，对于颅内动静脉畸形的患者，怀孕的妇女在妊娠期间发生血管破裂和出血的危险，比未怀孕的妇女明显高出8%。

　　该研究主要研究者哈佛医学院的专家 Bradley A. Gross博士和 Rose Du博士回顾了通过血管造影诊断动静脉畸形的54名妇女的病例资料。年出血率为随访中每年出血的病人数与病人总数之比。随访的患者年的计算是假定从出生病灶即存在直到AVM闭塞。将妊娠期出血Cox比例风险模型作为事件依赖性变量用来计算风险比。

　　研究结果发现在62怀孕中出现5次出血，每次怀孕出血的发生率为8.1％，而每年出血发生率为10.8%。在随访的2461.3患者年中，有28例出血发生，平均每年有1.1％出血率。妊娠期间出血的风险与未妊娠妇女相比，高出7.91倍（P =2.23×10），而40岁以上的AVM患者，这一比例则提高到18.12（P =7.31×10）。

　　尽管该研究研究的病例数较少，但其结果强烈提示AVM患者在妊娠期有明显更高的出血风险。在发生的四例AVM出血事件，在妊娠第22周到第39周发生突然头痛和其他的症状。尽管经过及时的治疗患者及胎儿均存活下来，但其中一位母亲还是落下了终身残疾。

　　基于以上研究的结论，研究有如下推荐：

　　对于那些希望生育的AVM患者，应及早进行干预治疗，特别是既往已有AVM出血的患者。

　　对于在妊娠期间新发现AVM的患者。若AVM已破裂，需早期干预；如果未破裂的AVM，建议进行综合评估，权衡干预和不干预对于继续妊娠的风险。

　　专家组推荐以剖宫产的方式分娩，并指出医务人员或医疗机构亦可建议不同的分娩方式。

　　总之，专家表示希望他们的发现和建议将引起人们的思考，并希望那些已知患有AVM但并未治疗的妇女在计划妊娠的事情上更加谨慎。

　　Hemorrhage from arteriovenous malformations during pregnancy.

　　Gross BA, Du R.

　　Department of Neurological Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA.

　　Abstract

　　BACKGROUND:

　　Previous hemorrhage, deep venous drainage, and deep location are established risk factors for arteriovenous malformation (AVM) hemorrhage. Although pregnancy is an assumed risk factor, there is a relative paucity of data to support this neurosurgical tenet.

　　OBJECTIVE:

　　To elucidate the hemorrhage rate of AVMs during pregnancy.

　　METHODS:

　　We reviewed the records of 54 women with an angiographic diagnosis of an AVM at our institution. Annual hemorrhage rates were calculated as the ratio of the number of bleeds to total number of patient-years of follow-up. Patient-years of follow-up were tallied assuming lesion presence from birth until AVM obliteration. The Cox proportional hazards model for hemorrhage with pregnancy as the time-dependent variable was used to calculate the hazard ratio.

　　RESULTS:

　　Five hemorrhages in 4 patients occurred over 62 pregnancies, yielding a hemorrhage rate of 8.1% per pregnancy or 10.8% per year. Over the remaining 2461.3 patient-years of follow-up, only 28 hemorrhages occurred, yielding an annual hemorrhage rate of 1.1%. The hazard ratio for hemorrhage during pregnancy was 7.91 (P = 2.23 × 10(-4)), increasing to 18.12 (P = 7.31 × 10(-5)) when limiting the analysis to patient follow-up up to age 40.

　　CONCLUSION:

　　Because of the increased risk of hemorrhage from AVMs during pregnancy, we recommend intervention in women who desire to bear children, particularly if the AVM has bled. If the AVM is discovered during pregnancy, we recommend early intervention if it has ruptured; if it is unruptured, we recommend comprehensive counseling, weighing risks of intervention against continuation of pregnancy without intervention.