Pivarnik J M, Mauer M B, Ayres N A, Kirshon B, Dildy G A, Cotton D B
Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston.
Obstet Gynecol. 1994 Feb;83(2):265-9.
To compare blood volumes and hematologic indices between nine aerobically trained, physically active pregnant women who continued to exercise throughout gestation and five healthy yet sedentary gravidas.
Subjects were tested on three occasions: 25 and 36 weeks of pregnancy and 12 weeks postpartum. Plasma volumes were estimated by dye dilution with Evans blue. Blood samples were taken from the antecubital vein with the subjects resting in a seated, semirecumbent position. In addition to plasma volume estimations, blood samples were analyzed for hematocrit ratio, hemoglobin concentration, red cell count, and plasma protein concentration. Blood volumes and red cell volumes were calculated from plasma volume estimates and hematocrit ratios.
Average birth weight and length of gestation did not differ between the subject groups. Analysis of variance indicated that absolute blood volume measures were significantly greater (P < .01) in the physically active compared to sedentary subjects at all three test times. Similar results were found for plasma and red cell volumes (P < .01). Blood volumes relative to body weight were significantly higher in physically active subjects (P < .01) than in their sedentary counterparts at 25 weeks (88.5 versus 75.5 mL/kg) and at 36 weeks (88.4 versus 70.9 mL/kg), as well as at 12 weeks postpartum (72.2 versus 57.6 mL/kg). All vascular volumes were significantly (P < .001) lower at 12 weeks postpartum compared to those seen during pregnancy in both subject groups. Hematologic indices of hematocrit ratio, hemoglobin concentration, red cell count, and plasma protein concentration were all greater (P < .001) at 12 weeks postpartum than during pregnancy.
Physically active women possessed significantly greater vascular volumes than their sedentary counterparts. Although this difference was maintained throughout gestation as the active gravidas continued to exercise, there was no apparent effect on pregnancy outcome.
比较九名在整个孕期持续进行有氧运动、身体活跃的孕妇与五名健康但久坐的孕妇之间的血容量和血液学指标。
对受试者进行三次测试:妊娠25周、36周以及产后12周。采用伊文思蓝染料稀释法估算血浆容量。受试者坐在半卧位休息时,从前臂肘静脉采集血样。除了估算血浆容量外,还对血样进行血细胞比容、血红蛋白浓度、红细胞计数和血浆蛋白浓度分析。根据血浆容量估算值和血细胞比容计算血容量和红细胞容量。
两组受试者的平均出生体重和妊娠期长度没有差异。方差分析表明,在所有三个测试时间点,身体活跃的受试者的绝对血容量测量值均显著高于久坐的受试者(P <.01)。血浆和红细胞容量也得到了类似结果(P <.01)。在妊娠25周(88.5对75.5 mL/kg)、36周(88.4对70.9 mL/kg)以及产后12周(72.2对57.6 mL/kg)时,身体活跃的受试者相对于体重的血容量显著高于久坐的受试者(P <.01)。与孕期相比,两组受试者在产后12周时所有血管容量均显著降低(P <.001)。产后12周时血细胞比容、血红蛋白浓度、红细胞计数和血浆蛋白浓度等血液学指标均高于孕期(P <.001)。
身体活跃的女性比久坐的女性拥有显著更大的血管容量。尽管随着活跃孕妇持续运动,这种差异在整个孕期都得以维持,但对妊娠结局没有明显影响。