Iams J D, Goldsmith L T, Weiss G
The National Institute of Child Health and Human Development Maternal Fetal Medicine Network, Bethesda, Maryland, USA.
J Soc Gynecol Investig. 2001 Jan-Feb;8(1):39-42.
The risk of spontaneous preterm birth has been related to decreased cervical length and to increased serum relaxin. To explore a relationship between these findings, we used data collected from two prior studies to correlate relaxin levels with cervical length and risk of spontaneous preterm birth in women with twin pregnancies.
In a secondary analysis of data collected in two previous observational studies of risk factors for preterm birth, relaxin levels in maternal serum and cervical length were measured at 24 (n= 188) and 28 (n= 145) weeks in women with spontaneous twin pregnancies. Relaxin, as a continuous variable, was related by logistic regression analysis to risk of spontaneous preterm birth before 37, 35, and 32 weeks' gestation, and by Spearman correlation coefficients to cervical length at 24 and 28 weeks. Cervical length at 24 weeks was known to be correlated with spontaneous preterm birth before 37, 35, and 32 weeks (P =.03,.01, and.002, respectively) in this study population.
Cervical length did not correlate with relaxin levels at 24 (P=.601) or 28 (P=.304) weeks. Relationships between relaxin and spontaneous preterm birth were observed at 24 weeks for births before 37 weeks (odds ratio [OR] 1.56, 95% confidence interval [CI] 1.00, 2.44; P=.05), and at 28 weeks for births before 35 weeks (OR 1.97, 95% CI 1.05, 3.70; P=.034) and 32 weeks (OR 2.43, 95% CI 1.01, 5.83; P=.048).
The absence of an association between relaxin and cervical length suggests that increased relaxin does not explain the inverse correlation between cervical length and spontaneous preterm birth in women with spontaneous twin pregnancies.
自发性早产风险与宫颈长度缩短及血清松弛素水平升高有关。为探究这些发现之间的关系，我们使用了从两项先前研究中收集的数据，以关联双胎妊娠女性的松弛素水平与宫颈长度及自发性早产风险。
在对两项先前关于早产风险因素的观察性研究中收集的数据进行二次分析时，对自发性双胎妊娠女性在孕24周（n = 188）和28周（n = 145）时的母血松弛素水平和宫颈长度进行了测量。作为连续变量的松弛素，通过逻辑回归分析与妊娠37、35和32周前的自发性早产风险相关，并通过Spearman相关系数与24周和28周时的宫颈长度相关。在该研究人群中，已知孕24周时的宫颈长度与妊娠37、35和32周前的自发性早产相关（P分别为0.03、0.01和0.002）。
宫颈长度在24周（P = 0.601）或28周（P = 0.304）时与松弛素水平无相关性。在24周时，观察到松弛素与妊娠37周前的早产之间存在关联（比值比[OR] 1.56，95%置信区间[CI] 1.00，2.44；P = 0.05）；在28周时，观察到松弛素与妊娠35周前（OR 1.97，95% CI 1.05，3.70；P = 0.034）和32周前（OR 2.43，95% CI 1.01，5.83；P = 0.048）的早产之间存在关联。
松弛素与宫颈长度之间缺乏关联表明，松弛素水平升高并不能解释自发性双胎妊娠女性宫颈长度与自发性早产之间的负相关关系。
