背景: 孕期下肢水腫是懷孕末期常見的生理變化，發生率為50%~80%，使懷孕婦女經驗到不舒適的症狀困擾，包含足部腫脹、疼痛、下肢沉重、爆裂感、及出現止痛的步態，嚴重的足部腫脹和疼痛而限制身體活動與社交能力，甚至感到疲憊。懷孕期間缺少身體活動，會增加孕期下肢水腫與疲憊程度並降低活力。然而，孕期下肢水腫為正常的生理變化而不被重視，隨著懷孕週數增加，下肢水腫程度對於孕期日常生活活動有著不同程度的影響。無論如何，孕期疲憊程度可能受下肢水腫與身體活動的影響，孕期疲憊程度更會影響整個懷孕過程或生產結果。已有許多研究探討孕期症狀與疲憊的關係，然而鮮少研究探討下肢水腫、身體活動與孕期疲憊的關係，彼此之間關係為何，目前仍未有研究做進一步探討。
目的: 長期追蹤孕期下肢水腫、身體活動與疲憊變化及影響孕期疲憊之因素。Specific aims 1、探討隨著懷孕週數增加其下肢水腫、身體總活動熱量消耗、疲憊與時間的關係。2、分別探討隨著懷孕週數增加其下肢水腫程度與疲憊關係、下肢水腫困擾與疲憊關係，以及身體總活動熱量消耗與疲憊關係。3、探討隨著懷孕週數增 加，影響孕期疲憊之因素。
方法: 本研究為前瞻性世代研究設計(prospective cohort study)，以方便取樣 (convenience sampling)，固定樣本進行三次資料收集，Time Ⅰ 懷孕28~30 週、Time Ⅱ 32~35週，Time Ⅲ 35週以上，收案地點在南台灣某醫學中心及婦幼 診所之產檢櫃台進行收案，招募期間為2019年10月~2020年8月，收案條件為20 歲以上、懷孕28~30週，初次資料收集無產科合併(如PIH、GDM 或前置胎盤)之孕婦；排除條件為腿部受傷、感染與手術、慢性腎臟、心臟疾病、高血壓、下肢淋巴水腫病史，以及被診斷有精神疾患者。測量工具包含凹陷性水腫量表、下肢 水腫困症狀困擾問卷、孕期身體活動問卷，以及疲憊量表。使用混合線性模式 (linear mixed model) 分析隨著懷孕週數增加其下肢水腫程度、下肢水腫症狀困 擾、身體總活動熱量消耗、疲憊程度與時間的變化關係；採多層次模式 (multilevel models, MLM) 分析下肢水腫程度、下肢水腫症狀困擾程度、身體總活動熱量消耗與孕期疲憊之關係，以及影響孕期疲憊的影響因素。
結果: 本研究在第一次資料收集(Time Ⅰ)有效樣本數為205人、Time Ⅱ 為199人，Time Ⅲ為183人，樣本折損率為10.7%，受試者平均年齡為34.19歲，初產婦約 (n=127, 61%)。隨著孕期週數，孕期下肢水腫程度(Time Ⅰ 到Time Ⅱ:β=0.854 , p < .001; Time Ⅰ到Time Ⅲ:β=1.443, p < .001)、下肢水腫症狀困擾程度有逐漸 上升的趨勢 (Time Ⅰ到Time Ⅱ:β=0.190, p < .001; Time Ⅰ 到 Time Ⅲ:β=0.405, p < .001)；孕期身體活動總熱量消耗 (Time Ⅰ 到Time Ⅱ:β= - 0.661, p < .05; Time Ⅰ 到Time Ⅲ:β= -0.674, p < .01)隨著孕期週數的增加有逐漸減少的趨勢；孕期疲憊程度(Time Ⅰ ~到Time Ⅱ:β=0.238, p < .01；Time Ⅰ 到Time Ⅲ:β=0.371, p < .01) 隨著孕期週數的增加有逐漸上升的趨勢。多層模式次分析結果顯示，以ModelⅠ- levelⅡ為最佳的模式配適度，對孕期疲憊程度解釋力約24 %，可預測孕期疲憊程度解釋變項包含個人疲憊初始平均分數 (intercept) (β=5.560, p < .000)、下肢水腫程度第一次測量資料 (β= -0.282, p < .01)、下肢水腫症狀困擾程度第一次測量資料(β= 0.745, p < .001)、下肢水腫症狀困擾程度改變量 (β= 0.638, p < .001)，身體活動總熱量消耗程度第一次測量資料(β= 0.052, p < .05) ，以及每各月經濟收入(β= 0.871, p < .05)。隨著孕期週數的增加，下肢水腫症狀困擾及身體活動總熱量消耗程度與疲憊程度呈正向預測效果，表示下肢水腫困擾程度愈高，以及身體總活動熱量消耗愈多則孕期的疲憊程度愈高；孕期下肢水腫程度與孕期疲憊程度呈負向的預測效果，表示下肢水腫程度愈嚴重則孕期的 疲憊程度低。
結論: 本研究顯示孕期下肢水腫、下肢水腫症狀困擾、身體總活動及孕期疲憊會受到懷孕週數的影響；孕期疲憊受到經濟收入、下肢水腫程度、下肢水腫症狀 困擾、及身體總活動影響，此結果有助於建立孕期下肢水腫、身體活動與孕期疲憊長期趨勢變化的實證性資料，強化醫療專業人員重視孕期下肢水腫症狀與困擾，對於孕婦足部健康和疲憊的影響，建議未來研究進一步探討身體活動在下肢水腫程度與孕期疲憊之間的關係。

Background: Lower limb edema commonly occurs in the third trimester, with an incidence rate of about 50%~80%. Pregnant women with lower limb edema experienced uncomfortable symptoms, including severe swelling and foot pain, which can limit physical and social activity and even cause fatigue. Additionally, pregnant women who lacked physical activity experienced increased lower limb edema, fatigue, and reduced vigor. Nevertheless, these health issues of pregnant women with lower limb edema have been neglected because it is a normal physiological change. As gestational age increases, lower limb edema causes uncomfortable symptoms and has different levels of influence on pregnant women’s daily life activity. However, fatigue could affect the consequences of the pregnancy or birth process. Several studies have explored the relationship among symptoms with the levels of fatigue during pregnancy. Nevertheless, only a few studies explored the relationships between the lower limb edema, physical activity and fatigue. At present, studies of current clinical practice leave the relationship between the lower limb edema, physical activity, and fatigue during pregnancy unexplored.
Objective: The study purposes were to investigate that the temporal changes and related factors were explored in regards to lower limb edema (including degree of lower limb edema and disturbance of the lower limb edema), physical activity, and fatigue. Specific aims; First, to explore trend changes related to lower limb edema, physical activity, and fatigue as gestational weeks increase. Second, the study investigated each of the correlations between lower limb edema and fatigue; disturbance of lower limb edema and fatigue; and physical activity and fatigue, independently. Third, factors associated with the levels of fatigue as gestational age increases were explored.
Methods: This study was a closed cohort study that was conducted prospectively and investigated with three waves of data collection. Convenience sampling was used to recruit pregnant women from a medical center and private obstetrics clinics in Tainan from October 2019 to August 2020. Inclusion criteria of the subjects were above 20 years, in the 28th to 30th gestational week, and uncomplicated pregnancies (such as PIH or GDM) during the first wave of data collection. Exclusion criteria included pregnant women with leg injury, surgery, or infection; and mental disorders. The linear mixed model was used to analyze the trend change for lower limb edema, physical activity, and fatigue as the gestational weeks increased, and multilevel modes were used to analyze the trend change among lower limb edema, physical activity, and fatigue, implemented to predict the influencing factors of fatigue.
Results: The data has been collected from 205 participants in the first wave. In the first follow-up, 199 of those participants’ data was collected. Finally, a total of 183 participants completed the 3rd and final stage of the data collection process. The overall attrition rate was 10.7 %. The mean age of the subjects was 34.19 (± 4.14) years old. Most participants were primipara (n=127; 62 %). Effect of time on the results showed that the degree of lower limb edema (Time Ⅰ to Time Ⅱ:β=0.852 , p < .001; Time Ⅰ to Time Ⅲ:β=1.445, p < .001), the levels of disturbance of edema (Time Ⅰ to Time Ⅱ:β=0.190, p < .001; Time Ⅰ to Time Ⅲ:β=0.405, p < .001), and the levels of fatigue (Time Ⅰ to Time Ⅱ:β=0.238, p < .01；Time Ⅰ to Time Ⅲ:β=0.371, p < .01) increased as gestation weeks progressed; the levels of physical activity (Time Ⅰ to Time Ⅱ:β= - 0.661, p < .05; Time Ⅰ to Time Ⅲ:β= -0.674, p < .01) decreased as gestation weeks progressed in the mixed effect model. In the analysis of the multilevel mode, the results showed that the Model 1-levelⅡwas the best goodness-of-fit, which contributed to about 24% explained of the variance in the levels of fatigue. The levels of fatigue were predicted including the intercept (β= 5.560, p < .000), the degree of lower limb edema (ini) (β= -0.282, p < .01), disturbance of the lower limb edema (ini) (β= 0.745, p < .001), and total activity (ini) (β= 0.052, p < .05) from the first-time data collection. Additionally, this included the amount of change on the disturbance of the lower limb edema (β= 0.638, p < .001), and monthly income (β= 0.871, p < .05). Furthermore, the relationship between the degree of lower limb edema and the levels of fatigue had a negative prediction effect, indicating that a higher degree of lower limb edema resulted in lower levels of fatigue. The relationships with a positive prediction effect included the relationship between disturbance from the lower limb edema, physical activity and the levels of fatigue, indicating that higher levels of disturbance from the lower limb edema and physical activity resulted in higher levels of fatigue.
Conclusions: The overall results showed that the degree of lower limb edema, the disturbance of the lower limb edema, physical activity, and fatigue were affected by gestation weeks. The degree of lower limb edema, disturbance of the lower limb edema, and physical activity predicted the levels of fatigue. The results of the study can provide evidence data on the longer-term trend change among the lower limb edema, disturbance of the lower limb edema, physical activity, and fatigue relationship. This may enhance the attention paid by health care professionals to the lower limb edema and resulting symptoms of disturbance caused by foot health and fatigue, and the influence on pregnant women. Future research should explore role played by physical activity on the relationship between lower limb edema and fatigue.

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