Avagliano Laura, Locatelli Anna, Danti Luana, Felis Salvatore, Mecacci Federico, Bulfamante Gaetano Pietro
Unit of Obstetrics and Gynecology, Department of Health Sciences, San Paolo Hospital Medical School, University of Milano, Milano, Italy.
Department of Obstetrics and Gynecology, FMBBM, San Gerardo Hospital, University of Milano-Bicocca, Monza, Italy.
Early Hum Dev. 2015 May;91(5):339-43. doi: 10.1016/j.earlhumdev.2015.03.004. Epub 2015 Apr 11.
Fetal acidemia at birth is defined as a newborn condition wherein the cord blood pH value is less than 7.0. It could represent an association with newborn brain damage; therefore, it is important to investigate which conditions precipitate its occurrence. No extensive placental analysis has been performed in cases of acidotic newborns delivered from low-risk pregnancies.
To study placental characteristics in cases with severe fetal acidemia.
Retrospective case-control study.
34 cases, 102 controls.
Umbilical artery pH was measured at delivery from a doubly clamped portion of the cord. Placental characteristics were compared between cases with severe fetal acidemia (cord pH at birth <7.0) and controls (normal pH at birth) in term low-risk pregnancies.
Macroscopic placental and umbilical cord characteristics were comparable in cases and controls whereas histological characteristics exhibited differences: diffuse villous edema, increased number of syncytial knots and villous branching abnormalities significantly affected cases more frequently than controls. Diffuse villous edema is related to fetal vascularization and associated with an increase of venous pressure; in our low-risk population, it is conceivable that these changes of fetal flow and pressure occurred in labor during the alteration of fetal heart rate. An increased number of syncytial knots and villous branching abnormalities have been previously associated with chronic placental hypoxic condition; in our low-risk population they could reflect a clinically undetectable hypoxic situation that acted during pregnancy reducing fetal resources to bear labor and delivery.
Placental histology provides useful information related to fetal acidemia in low-risk term pregnancy.
出生时胎儿酸血症被定义为一种新生儿状况，即脐血pH值小于7.0。它可能与新生儿脑损伤有关；因此，调查哪些情况会促使其发生很重要。对于低风险妊娠分娩的酸中毒新生儿，尚未进行广泛的胎盘分析。
研究严重胎儿酸血症病例的胎盘特征。
回顾性病例对照研究。
34例病例，102例对照。
在分娩时从脐带的双夹部位测量脐动脉pH值。比较足月低风险妊娠中严重胎儿酸血症病例（出生时脐带pH值<7.0）和对照（出生时pH值正常）的胎盘特征。
病例组和对照组的胎盘和脐带宏观特征具有可比性，而组织学特征存在差异：弥漫性绒毛水肿、合体结节数量增加和绒毛分支异常在病例组中比对照组更频繁地受到显著影响。弥漫性绒毛水肿与胎儿血管形成有关，并与静脉压升高有关；在我们的低风险人群中，可以想象这些胎儿血流和压力的变化发生在分娩期间胎儿心率改变时。合体结节数量增加和绒毛分支异常先前已与慢性胎盘缺氧状况相关；在我们的低风险人群中，它们可能反映了一种临床上无法检测到的缺氧情况，这种情况在怀孕期间起作用，减少了胎儿承受分娩的资源。
胎盘组织学为低风险足月妊娠中与胎儿酸血症相关的情况提供了有用信息。
