PRENATAL DIAGNOSIS OF CONGENITAL ANOMALIES

该项目的目标是提高诊断和治疗 胎儿疾病过去，分支率先使用 薄规格胚胎胎儿镜检查和内窥镜胎儿手术， 多胎妊娠疾病的治疗。今年的努力是 重点是检查怀孕日期的准确性， 怀孕中期 孕龄评估是产前护理的一个组成部分。 不准确的年龄分配会导致错误率的增加。 阳性和假阴性病例，诊断错误，以及不必要的 侵入性手术分配持续时间的标准方法 怀孕是月经年龄，准确性取决于可靠性 月经史 然而，多达45%的孕妇 次优月经史 到目前为止，最受欢迎的替代方案 确定日期的方法是用超声波进行胎儿生物测量。 围产期 研究分支与康奈尔大学合作进行了一项研究 大学医学中心确定胎儿生物测量的准确性 在14至22周之间预测胎龄， 基于患者人群的单胎、双胎和三胎妊娠 通过体外受精受孕的人 的结果 研究表明，胎儿头围的大小是最重要的 准确预测所有研究参数的胎龄。 的 增加一个参数（腹围或股骨长度）或 两个（腹围和股骨长度）显着改善了 仅基于头围的预测的准确性。 的 在大多数产科单位的临床实践中， LMP的胎龄与推导的胎龄不一致超过14天 根据妊娠中期的胎儿生物统计学，LMP评估是 被胎儿生物特征所取代 我们的研究表明， 两者之间存在超过7天的生物特征预测， 如果没有先天性异常， 严重的生长迟缓。 这项研究的一个主要发现是， 单胎妊娠可用于多胎妊娠。 一 两对双胞胎胎龄预测的简单平均值为 这是一个准确的年龄预测。 在三胞胎的情况下， 天可以添加到最长和最短妊娠期的平均值 三胞胎的年龄预测 我们的观察表明胎儿 期间，双胎妊娠的增长速度与单胎妊娠相似 怀孕中期 然而，20至22周之间的三胞胎数据是 这意味着增长减速，这一问题需要进一步 调查 我们观察到胎龄的差异 多胎妊娠成员的预测平均为2.2天， 双胞胎（最大= 7.2天）和三胞胎4.2天（最大= 10.8 天）。 因此，当多个成员之间的差异 怀孕两周或更长时间，寻找胎儿生长障碍， 先天性异常或测量误差是合理的。

The goal of this project is to improve the diagnosis and treatment of fetal disease. In the past, the Branch has pioneered the used of thin-gauge embryo-fetoscopy and endoscopic fetal surgery for the treatment of disorders of multiple gestation. This year the effort was focused on examining the accuracy of dating of pregnancy in the midtrimester. Gestational age assessment is an integral part of prenatal care. Inaccurate age assignment results in an increase in the rate of false positive and false negative cases, diagnostic errors, and unnecessary invasive procedures. The standard method of assigning duration of pregnancy is menstrual age and accuracy is dependent upon the reliability of menstrual history. However, as many as 45% of pregnant women had sub-optimal menstrual history. By far, the most popular alternative method of dating is fetal biometry with ultrasound. The Perinatology Research Branch conducted a study in collaboration with the Cornell University Medical Center to determine the accuracy of fetal biometry between 14 and 22 weeks in the prediction of gestational age in singleton, twin and triple gestations based upon population of patients who conceived as a result of in vitro fertilization. The results of this study demonstrated the size of the fetal head circumference was the most accurate predictor of gestational age of all parameters studied. The addition of one parameter (abdominal circumference or femur length) or two (abdominal circumference and femur length) significantly improved the accuracy of the prediction based on head circumference alone. The clinical practice in most obstetrical units is that discrepancy between gestational age by LMP disagrees by more than 14 days with that derived from fetal biometry in the second trimester, the LMP assessment is superseded by fetal biometry. Our study suggests that when a discrepancy of more than 7 days exists between the two, the biometric prediction should be given preference, provided there is no congenital anomaly or severe growth delay. A major finding of the study was that the dating formulae derived from singleton gestations can be used for dating multiple pregnancies. A simple average of the gestational age prediction of the two twins was found to be an accurate predictor of age. In the case of triplets, one day can be added to the average of the longest and shortest gestational age prediction among the triplets. Our observations imply that fetuses of twin gestations grow at a similar rate to singleton gestations during the midtrimester. However, data on triplets between 20 and 22 weeks is suggestive of a deceleration of growth, an issue which requires further investigation. We observed that the difference in the gestational age prediction among members of a multiple gestation averaged 2.2 days for twins (maximum = 7.2 days) and 4.2 days for triplets (maximum = 10.8 days). Therefore, when the difference among members of multiple gestation is two weeks or more, a search for fetal growth disorders, congenital anomalies, or a measurement error is justified.