Does the first trimester of pregnancy induce alterations in the walking pattern?

IntroductionFrom among many studies observing the walking pattern throughout pregnancy, only two items monitor the influence of pregnancy on the movement system during gait considering the period before gestation.Research questionDoes the women’s gait pattern at the end of the first trimester undergo changes in comparison to body movement pattern before pregnancy?MethodsAll subjects who met the inclusion criteria gave signed and informed consent before the study. Two experimental sessions were arranged according to the same protocol: (P0) before pregnancy and (P1) at the end of the first trimester of pregnancy (12th week of gestation). At first the anthropometric measures were taken. Then, walking trials at a self-selected speed along a walkway were registered with Vicon 250 (Oxford Metrics Ltd.; Oxford, UK) and FreeMED force platform (Sensor Medica, Italy).ResultsAn analysis of anthropometric parameters in 12th pregnancy week demonstrated significant changes in mean values of waist circumference and waist to hip ratio as well as waist to height ratio indexes compared to the results before pregnancy. No significant differences were found in the basic kinematic gait parameters between experimental conditions. Significant increase of mean inter—ankle distance during double support phase occurred during the first trimester of pregnancy. Also, the ratio of the ankle separation width to the pelvic width was noticeably higher in gestation. Then, angular changes of the pelvis in coronal and transverse planes throughout gait cycle during pregnancy demonstrated significant differences compared to those measured before pregnancy. At the same time in the first trimester of pregnancy no adaptive changes in the pattern of feet loading take place.SignificanceSince our study is of longitudinal character, in the course of pregnancy we expect compensatory mechanisms more clearly demonstrated. Therefore, we hope to identify a strategy of the gravid body progression in space.引言：在诸多针对孕期行走模式的研究中，仅有两项研究在考量妊娠前阶段的前提下，探究了孕期步态中妊娠对运动系统的影响。 研究问题：相较于妊娠前的身体运动模式，妊娠早期结束时（即妊娠第12周）女性的步态模式是否发生了变化？ 研究方法：所有符合纳入标准的受试者均在研究开始前签署了知情同意书。本研究按照统一方案开展两次实验采集：一次为妊娠前（P0），另一次为妊娠早期结束时（即妊娠第12周，P1）。首先采集人体测量学指标，随后让受试者以自选速度在步道上行走，使用Vicon 250（Oxford Metrics Ltd.; 英国牛津）与FreeMED测力台（Sensor Medica, 意大利）记录行走试验数据。 研究结果：对妊娠第12周的人体测量学参数进行分析后发现，相较于妊娠前，受试者的腰围、腰臀比以及腰高比的均值均发生了显著变化。两种实验条件下的基础运动学步态参数未发现显著差异。妊娠早期时，双支撑阶段的平均踝间距显著增大，且踝间距与骨盆宽度的比值在孕期明显升高。此外，相较于妊娠前的测量结果，孕期整个步态周期中骨盆在冠状面与横断面的角度变化均存在显著差异。与此同时，妊娠早期受试者的足部负重模式未出现适应性变化。 研究意义：由于本研究属于纵向研究，我们预期在孕期过程中代偿机制将得到更清晰的展现。因此，本研究希望阐明妊娠机体在空间中的运动适应策略。