Arduini D, Rizzo G, Rinaldo D, Capponi A, Fittipaldi G, Giannini F, Romanini C
Department of Obstetrics and Gynecology, Università di Ancona, Italy.
Gynecol Obstet Invest. 1994;38(3):177-82. doi: 10.1159/000292474.
The objective of this study was to evaluate whether Braxton-Hicks contractions induce changes in fetal heart rate variation in normal and growth-retarded fetuses. 110 uncomplicated singleton pregnancies were cross-sectionally studied as well as 16 pregnancies complicated by fetal growth retardation secondary to uteroplacental insufficiency. Fetal heart rate variability was analyzed by a commercially available computerized system (2CTG Hewlett Packard, Italy) 10 min before and 10 min after the Braxton-Hicks contraction. All the included fetal heart rate tracings fulfilled the following criteria: (1) presence of a single Braxton-Hicks contraction in the 20 min considered; (2) absence of fetal heart rate decelerations after the contraction, and (3) stable fetal heart rate behavioral pattern in the period analyzed. 82 tracings of normal fetuses were analyzed during an active fetal heart rate pattern (type B) and the remaining 28 during a quiet pattern (type A). In both patterns no significant differences in delta value, long-term irregularity, short-term variability and interval index were found before and after the contraction. All the tracings of growth-retarded fetuses were analyzed during the fetal heart rate pattern A. Short-term variation and interval index significantly decreased during the first 5 min after the contraction while no significant differences were found in the other indices investigated. The decrease in these indices was significantly more marked in those fetuses developing fetal distress within 7 days. In conclusion, Braxton-Hicks contractions induce a significant decrease of short-term variation and interval index only in growth-retarded fetuses. This can be useful in the early identification of fetal compromise in such fetuses.
本研究的目的是评估在正常胎儿和生长受限胎儿中，布拉克斯顿-希克斯宫缩是否会引起胎儿心率变异性的变化。对110例无并发症的单胎妊娠进行了横断面研究，以及16例因子宫胎盘功能不全继发胎儿生长受限的妊娠。在布拉克斯顿-希克斯宫缩前10分钟和后10分钟，使用商用计算机系统（意大利惠普2CTG）分析胎儿心率变异性。所有纳入的胎儿心率描记图均符合以下标准：（1）在考虑的20分钟内出现一次布拉克斯顿-希克斯宫缩；（2）宫缩后无胎儿心率减速；（3）在分析期间胎儿心率行为模式稳定。在胎儿心率活跃模式（B型）下分析了82例正常胎儿的描记图，其余28例在安静模式（A型）下分析。在两种模式下，宫缩前后的δ值、长期不规则性、短期变异性和间期指数均无显著差异。所有生长受限胎儿的描记图均在胎儿心率模式A下进行分析。宫缩后前5分钟内，短期变异性和间期指数显著降低，而在其他研究指标中未发现显著差异。在7天内发生胎儿窘迫的胎儿中，这些指标的下降更为明显。总之，布拉克斯顿-希克斯宫缩仅在生长受限胎儿中引起短期变异性和间期指数的显著降低。这有助于早期识别此类胎儿的胎儿窘迫。
