懷孕到產後飲食營養與體重變化之前瞻性研究

Abstract

懷孕期體重增加過多與產後體重保留為造成產後婦女肥胖的一個危險因子，因此本研究希望藉由前瞻性實驗設計，以面對面及電話訪談方式來收集懷孕初期到產後六個月的長期飲食及體重相關資料，以探討影響產後體重變化之因素。研究方法以前驅性問卷調查法追蹤受試者從懷孕初期到生產後六個月每個月的飲食攝取情況、生活型態以及體重變化情形。研究時間從91年10月到93年1月；研究對象以台北市市立婦幼醫院懷孕週數在20周以內的孕婦為樣本，共招募了151位孕婦，在產六個月為止退出率為14%，最後共有130名產婦完成產後六個月訪談問卷。研究工具主要為自行發展的結構性問卷，包括個人基本資料問卷、健康狀況家庭生活及個人飲食頻率問卷、一週飲食及活動頻率問卷、24小時飲食回憶問卷、三天飲食記錄等。研究分析方法採用spss10.0版來進行，包括了描述性統計分析、變異數分析、斯皮爾曼等級相關、群集分析、多變項分析和GEE分析等。

在本研究中，受試者平均年齡為30歲、有50%的產婦為初產婦，且有7成的產婦在產後第一個月時有餵哺母乳，平均哺乳時間為三個月，且產婦在孕期體重平均增加14.23公斤。在體重變化方面，產婦在產後六個月時體重平均比未生產前增加2.4公斤，由未懷孕前的53.35公斤增加到55.75公斤；BMI值由20.95kg/m 增加為21.89kg/m ，平均增加0.94kg/m 。在飲食攝取方面，由24小時飲食回憶法得知產婦在坐月子時期與產後2-6個月之平均熱量攝取分別為1836kcal和1737kcal。

研究分析主要發現：1.懷孕期體重增加量與產後體重保留呈強正相關(r=0.54，p＜0.01)。2.坐月子期和產後平均熱量攝取與產後體重保留呈正相關。3.產後體重保留和產後每個月的活動量呈負相關。4. 年齡、哺乳與與產後體重保留無關，但可能與哺乳期間長短有關。5.當產婦是經產婦時，其產後六個月的BMI值會比初產婦來的高。6.由多元迴歸分析中發現，當控制住產婦年齡、社經地位、身體活動量時，其未生本胎次之前BMI值、孕期體重增加量、產後平均熱量攝取、產後熱量變化量、產後每公斤體重熱量攝取變化值(kcal/kg)等變項可解釋產後體重保留64.8%的變異量。因此，研究建議產婦要控制好孕期體重增加量，降低坐月子期間及產後平均熱量攝取，在產後保持規律的運動，有助於預防產後肥胖的情形發生Excessive gestational weight gain and resulting postpartum weight retention are risk factors to develop obesity for women. This study was to examine the diet and weight history with a prospective follow-up design by face-to-face and telephone interviews from early pregnancy to six month postpartum. We recruited 151 pregnant women within 20 weeks pregnancy at Taipei Municipal Women and Children Hospital and follow them from Oct. 2002 to Jan. 2004 and conducted monthly interviews by structures questionnaires including basic information, food frequency, weekly food frequency, 24-hour recalls and food records. At six month postpartum, total 130 subjects completed these interviews with a loss of follow-up rate of 14%. The statistical analyses including descriptive statistics, correlations, cluster analysis and multiple regression analyses were performed by Spss version 10.0.

The pregnant participants had an average age of 30 years old with 50% were first pregnant and the average gestational weight gain was 14.2kg.There were 70% of them breastfed the infant at the first month and the average breastfeeding time was 3 months. Concerning the change in weight, the average weight retention was 2.4 kg (from 53.4kg to 55.8kg) and 0.94 kg/m2 at six month postpartum. The relevant issue of dietary intake is show in the fact that average energy intake of first month postpartum was 1837 Kcal and between postpartum 2-6 months was 1737 kcal by 24-hour dietary recalls.

The main results are: 1. There was a significant positive correlation between gestational weight gain and postpartum weight retention (r=0.54, p<0.05). 2. Energy intakes during the first month postpartum and from 2 to 6 month postpartum were positively correlated with weight retention. 3. Physical activity level was negatively associated with postpartum weight retention. 4. Age and breastfeeding are not related to postpartum weight retention, but breastfeeding duration may associate with postpartum weight retention. 5. The multiparous women had higher BMI than nulliparous women at six month postpartum. 6. After controlling for age, socioeconomic status and physical activity levels, pre-pregnancy BMI, gestational weight gain, postpartum average energy intakes, postpartum energy decreases, and changes for energy consumption per Kg (Kcal/Kg) can explain 62% variation of postpartum weight retention.

In conclusion, our results suggested pregnant women should be advised to control gestational weight gain, decrease energy intakes after bearing and keep regular exercise in order to prevent postpartum obesity