背景:怀孕期间肥胖很常见,超过50%的孕妇超重或肥胖。肥胖已被确定为功能失调的独立预测因素,并且与导致剖宫产的引产失败风险增加有关。瘦素,脂肪因子,在肥胖基因的控制下从脂肪组织分泌。瘦素的浓度随着身体脂肪百分比的增加而增加,这是由于肥胖个体的脂肪组织产生的瘦素增加。有趣的是,胎盘也是怀孕期间产生瘦素的主要来源。瘦素对神经元组织有调节作用,血管平滑肌,和非血管平滑肌系统。还已经证明,瘦素对子宫肌层收缩具有抑制作用,收缩的强度和频率均降低。这些发现表明,瘦素可能在功能失调的分娩中起重要作用,并与足月引产的结果有关。我们的目的是确定母体血浆瘦素浓度是否指示足月引产的结果。我们假设母体血浆瘦素水平升高与导致剖宫产的足月引产失败有关。
方法:在本病例对照研究中,在妊娠晚期血浆样品中测量瘦素。为了分析劳动结果,174名妇女是根据接受过引产(IOL)选择的,(115名成功IOL的女性和59名失败IOL的女性)。从UI母体胎儿组织库(IRB#200910784)获得血浆样品和临床信息。使用可商购的测定法测量母体血浆瘦素和总蛋白质浓度。双变量分析和逻辑回归模型是使用回归识别的临床显著混杂变量构建的。所有变量均以0.05的显著性水平进行测试。
结果:IOL失败的女性具有更高的母体血浆瘦素值(0.5比0.3pg,P=0.01)。这些女性更有可能患有肥胖症(平均BMI32vs27kg/m2,P=0.0002),并且需要多种诱导方法(93%vs73%,p=0.008)。Logistic回归显示Bishop评分(OR1.5,p<0.001),BMI(OR0.92,P<0.001),先兆子痫(OR0.12,P=0.010),使用多种诱导方法(OR0.22,P=0.008)和瘦素(OR0.42,P=0.017)与IOL结局显著相关.具体来说,在控制了BMI之后,BishopScore,先兆子痫,瘦素仍可预测IOL失败,比值比为0.47(P=0.046)。最后,使用瘦素作为胎儿结局的预测因子,瘦素也与胎儿分娩不耐受有关,比值比为2.3(P=0.027)。当控制成功(IOL)时,这种关联仍然存在,但未能达到统计学意义(OR1.5,P=0.50)。
结论:产妇血浆瘦素可能是一个有用的工具,用于确定哪些妇女可能引产失败,并为妇女提供关于引产与剖宫产的咨询。
BACKGROUND: Obesity in pregnancy is common, with more than 50% of pregnant women being overweight or obese. Obesity has been identified as an independent predictor of dysfunctional labor and is associated with increased risk of failed induction of labor resulting in cesarean section. Leptin, an adipokine, is secreted from adipose tissue under the control of the obesity gene. Concentrations of leptin increase with increasing percent body fat due to elevated leptin production from the adipose tissue of obese individuals. Interestingly, the placenta is also a major source of leptin production during pregnancy. Leptin has regulatory effects on neuronal tissue, vascular smooth muscle, and nonvascular smooth muscle systems. It has also been demonstrated that leptin has an inhibitory effect on myometrial contractility with both intensity and frequency of contractions decreased. These findings suggest that leptin may play an important role in dysfunctional labor and be associated with the outcome of induction of labor at term. Our aim is to determine whether maternal plasma leptin concentration is indicative of the outcome of induction of labor at term. We hypothesize that elevated maternal plasma leptin levels are associated with a failed term induction of labor resulting in a cesarean delivery.
METHODS: In this
case-control study, leptin was measured in 3rd trimester plasma samples. To analyze labor outcomes, 174 women were selected based on having undergone an induction of labor (IOL), (115 women with successful IOL and 59 women with a failed IOL). Plasma samples and clinical information were obtained from the UI Maternal Fetal Tissue Bank (IRB# 200910784). Maternal plasma leptin and total protein concentrations were measured using commercially available assays. Bivariate analyses and logistic regression models were constructed using regression identified clinically significant confounding variables. All variables were tested at significance level of 0.05.
RESULTS: Women with failed IOL had higher maternal plasma leptin values (0.5 vs 0.3 pg, P = 0.01). These women were more likely to have obesity (mean BMI 32 vs 27 kg/m2, P = 0.0002) as well as require multiple induction methods (93% vs 73%, p = 0.008). Logistic regression showed Bishop score (OR 1.5, p < 0.001), BMI (OR 0.92, P < 0.001), preeclampsia (OR 0.12, P = 0.010), use of multiple methods of induction (OR 0.22, P = 0.008) and leptin (OR 0.42, P = 0.017) were significantly associated with IOL outcome. Specifically, after controlling for BMI, Bishop Score, and preeclampsia, leptin was still predictive of a failed IOL with an odds ratio of 0.47 (P = 0.046). Finally, using leptin as a predictor for fetal outcomes, leptin was also associated with of fetal intolerance of labor, with an odds ratio of 2.3 (P = 0.027). This association remained but failed to meet statistical significance when controlling for successful (IOL) (OR 1.5, P = 0.50).
CONCLUSIONS: Maternal plasma leptin may be a useful tool for determining which women are likely to have a failed induction of labor and for counseling women about undertaking an induction of labor versus proceeding with cesarean delivery.