한국영양학회지 (Korean J Nutr) 2010; 43(2): 141 ~ 151 DOI 10.4163/kjn.2010.43.2.141 임신중체중증가에따른영양섭취및임신결과와의관련성 한영선 이상선 한양대학교식품영양학과 Association of Nutrient Intake and Pregnancy Outcome with Gestational Weight Gain Han, Young-Sun Lee, Sang-Sun Department of Food & Nutrition, Hanyang University, Seoul 133-791, Korea ABSTRACT Gestational age and infant birth weight are influenced by gestational weight gain. This study was aimed to examine the effects of gestational weight gain on pregnancy outcomes. Pregnant women were recruited at two hospitals in Seoul area. Characteristics and dietary intakes of pregnant women were obtained using 24-hour recall questionnaires. Gestational weight gain was categorized as less (Under-gain) than, within (Recommended gain), or greater (Over-gain) than the Institute of Medicine guidelines. Maternal height and pre-pregnancy weight in the over-gain group significantly higher than under-gain and recommended gain group. Mini dietary assessment score of eating bean has significantly higher in under-gain group than recommended gain group and eating kimchi has significantly higher in undergain group than over-gain group. Score of eating fruit was significantly higher in over-gain group than other groups. The mean intake of carbohydrate in the recommended gain group were significantly higher than under-gain group, and mean intake of potassium in the over-gain group were significantly higher than under-gain group. Under-gain group showed the high rate of the preterm delivery and low birth weight infant delivery. However recommended gain group showed 46% reduced risk of preterm delivery (OR = 0.54 CI = 0.30-0.98). Risk of macrosomia increased with increasing gestational weight gain (p for trend < 0.05). In conclusion, pregnancy outcomes were influenced by gestational weight gain. Therefore, these finding suggested adequate gestational weight gain according to BMI for reducing the risk of preterm delivery, low birth weight and macrosomia. (Korean J Nutr 2010; 43(2): 141 ~ 151) KEY WORDS : gestational weight gain, nutrient intake, pregnancy outcome. 서 임신중체중증가량이적을경우에저체중아를출산할위험이있는반면, 많을경우에는과체중아를출산할위험이있다고보고되었다. 1) 출생시신생아의체중은신생아의사망률, 아동기성장, 성인건강에중요한역할을하여출생시몸무게가적게나갔던사람들은심장질환, 고혈압, 고콜레스테롤농도, 당대사장애의위험이높아진다. 2) 하지만통계청에의한보고에따르면 1993~2008 년체중별출생현황에서 2.5 kg 이하인저체중아출생이 1993 년 18,532 명에서 2008 년 22,725 명으로증가하여 3) 이에대한임신 론 접수일 :2009 년 12 월 23 일 / 수정일 :2010 년 2 월 2 일채택일 :2010 년 03 월 25 일 To whom correspondence should be addressed. E-mail: leess@hanyang.ac.kr 부와저체중아의관리가요구된다. 조산은 1976 년세계보건기구 (World Health Organization: WHO) 의발표에따르면임신 37주이전에분만한경우로정의한다. 4) 우리나라뿐아니라미국을비롯한여러선진국에서도조산은주산기사망률및이환율의중요한원인이된다. 5) 따라서조산아발생률을감소시켜주산기사망률및이환율을줄이기위한노력이끊임없이시도되었지만조산율의감소추세는기대에미치지못하고있고 6) 오히려통계청에의한보고에따르면우리나라의조산율은 1996 년에 40,114 명에서 2008년에 62,869명으로증가하였다. 3) 연구들에서임신중산모의저체중증가와조산사이에유의적인상관관계가있음이보고되었다. 7,8) Nohr 등 9) 의연구에서는임신전과체중또는비만이거나임신기간동안체중이지나치게증가하면조기양막파수의위험이증가한다고보고되었다. Dietz 등 10) 의연구에서는임신중체중증가가한주에 0.79 kg 이상이면조산 (20~31 주 ) 이될위험 2010 The Korean Nutrition Society
142 / 임신중체중증가와영양섭취및임신결과 이거의 2배라고보고되었다. Fortner 등 11) 의연구에따르면 IOM (1990) 기준에서적정범위안으로체중이증가한임신부와비교할때, 임신중체중이지나치게증가한임신부는임신성고혈압에걸릴위험이약 3배높아지고자가전증에걸릴위험이 4배높아진다고보고되었다. 또한 Chen 등 12) 의연구에서도임신중체중증가가일주일에 0.50 kg 증가하거나이보다더많이증가하면임신성고혈압, 조기양막파수, 거대아출산의위험이높아지고일주일에 0.59 kg 이상증가한임신부는자가전증의위험이 3배증가하는것으로보고되어임신중지나친체중증가는좋지않은임신결과의위험을증가시킴을알수있다. 또한 Kabali & Werler 13) 의연구에서는임신전과체중이었던임신부와임신중체중이지나치게증가한임신부는거대아를출산할위험이높아진다고보고되었다. 국내에서임신중체중증가에따른조산, 신생아출생체중과같은임신결과에대한보고가일부있으나, 연구결과마다차이가있고임신부를대상으로한연구에서바람직한식습관에대해서연구된것은드물기때문에본연구에서이루어진임신중체중증가에따른임신결과에대한보고와식습관점수와영양소에대한분석은의미가있고임신부의바람직한식습관을제안하는데도움이될것으로사료된다. 연구방법연구대상자및기간 본연구는서울소재의종합병원산부인과로정기검진을받으러온제 2~3 분기 (19~39 주 ) 사이의임신부를대상으로설문지를통해조사가이루어졌다. 조사기간은 2006 년 4월부터 2009 년 4월까지였고, 미국 Institute of Medicine (IOM, 2009) 14) 의기준을근거로하여, 산모의임신전 BMI 에따라적절한체중증가를이룬산모군을적정증가군 (Recommended gain), IOM guidelines에서제시한기준의체중증가를이루지못한산모군을저증가군 (Undergain), 제시한기준보다더초과하여체증증가한산모군을초과증가군 (Over-gain) 이라고분류하여 (Table 1) 저증가군 191 명, 적정증가군 214 명, 초과증가군 145 명으로총 550 명을분석하였다. 임신중체중증가에따른분류에서영양소섭취에이용할수있는데이터는저증가군 130명, 적정증가군 145 명, 초과증가군 100 명으로총 375 명이었다. 조사내용및방법설문지는조사대상자의일반적특성및산과적특성, 신 Table 1. guidelines by Institute of medicine Category BMI (kg/m 2 ) Total weight gain (kg) Underweight < 18.5 12.5-18.0 Normal 18.5-24.9 11.5-16.0 Overweight 25.0-29.9 07.0-11.5 Obese > 30.0 5.0-9.0 was categorized as less (Under-gain) than, within (Recommended gain), or greater (Over-gain) than the Institute of Medicine guidelines according to pre-pregnancy BMI (IOM, 2009) 14 체계측치, 건강과관련된생활습관및식습관, 식이섭취실태등으로구성되었고훈련된연구원과조사대상자와의 1:1 면담을통해조사되었다. 일반적특성에관한사항으로는임신부의연령, 교육수준, 경제적수준, 직업유무, 가족수를조사하였고산과적특성으로는현재임신기간, 임신경험, 입덧여부에대하여조사하였다. 조사대상자의신장, 임신전체중과임신중체중은설문지에직접기입하도록하였고임신전체중을이용하여 BMI 를계산하였다. 건강과관련된생활습관으로는흡연, 음주, 커피섭취, 스트레스, 몸무게감소시도, 에너지를소비하는활동정도, 운동여부를조사하였다. 활동정도에서가벼운활동은하루에걷는시간과서있는시간이 2시간이하, 사무직, 일반가사, 아기없는전업주부등이포함되었고보통활동에는하루에걷는시간과서있는시간이 2~4 시간정도, 판매업, 교사, 실험실일등이포함되었으며심한활동에는하루에걷는시간과서있는시간 4~6 시간정도, 건설업, 농경작업, 테니스등이격심한활동에는거의앉지않고서고, 달리고, 일을하면서전신의근육을사용하는경우, 레슬링, 권투등의심한운동이포함되었다. 규칙적인운동을한기준은따로정하지않고규칙적인운동을하셨습니까? 의물음에예, 아니오로답하게하여예일경우운동의종류, 시간과주당운동횟수를기입하도록하였다. 스트레스요인의측정은 Holmes 와 Rache 15) 의사회재적응척도중에서결혼과임신으로인한생활사건중원치않는자녀, 가족관계, 경제적부담, 체형변형, 유전적질병의 5항목과임신으로인한상황적요인을참고로검토, 보완하여이용한김과이 16) 의연구를바탕으로총 41문항을 예 (1 점 ), 아니요 (0점 ) 로점수화하여 12점이상은스트레스가높은군, 12점미만은스트레스가낮은군으로분류하였다. 식생활태도는 13가지항목으로구성된간이식생활진단표 (MDA, Mini-Dietary Assessment) 17) 를이용하였고각항목의점수는 항상그런편이다 (3점 ), 보통이다 (2점), 아닌편이다 (1점 ) 로점수화하여점수가높을
한국영양학회지 (Korean J Nutr) 2010; 43(2): 141~151 / 143 수록식사의질이높아식생활태도가좋은것으로평가하였다. 영양소섭취조사및분석영양소섭취는식품의종류, 구성, 섭취량등을잘훈련된조사원에의해 24시간회상법을이용하여 1일의식이를조사하였다. 조사기간중특별한식사를한경우나외식을한경우는제외하고평소에먹는일상식을기록하도록하였다. 24시간회상법을이용하여얻은식이섭취자료를 CAN- Pro 3.0 분석프로그램을이용하여영양소섭취량을분석하였고영양소섭취상태를한국인영양섭취기준 (Dietary Reference Intakes For Koreans, KDRIs) 18) 과비교하였다. 먼저열량은필요추정량 (EER) 을이용하여 75% 이하와 125% 이상을섭취하는비율을비교하였고탄수화물은에너지적정비율을참고로하여 55% 이하와 70% 이상을섭취하는비율을비교하였고지방은 15% 이하와 25% 이상을섭취하는비율을비교하였다. 각영양소는평균필요량 (EAR) 이하, 충분섭취량 (AI) 이하, 상한섭취량 (UL) 이상으로분류하여대상자들의섭취비율을비교하였다. 영양소섭취량분석에는영양보충제의함량이포함되지않았다. 임신결과임신결과자료는병원의의료기록을수집하였다. 임신부의임신결과를나타내는항목으로분만직전체중, 임신기간을조사하였고분만직전체중과임신전체중으로임신 중총체중증가량을산출하였고신생아의임신결과를나타내는항목으로는출생시체중및키를조사하였다. 통계분석본연구는 SPSS (Statistical Package for Social Science 17.0) 를사용하였다. 연속변수측정값은 student s t-test 와 One-way ANOVA 를실시하여평균값과표준편차로나타내었고, One-way ANOVA 는 p < 0.05 수준에서 Tukey test 로사후분석을하여각군간의유의적인차이를검증하였다. 명목변수비율은 Chi-square test를이용하여개체수와백분율로나타내었다. 임신전 BMI 와임신중체중증가에따른조산, 저체중아, 과체중아의 Odds ratio (OR) 와 95% 신뢰구간 (95% confidence interval, CI) 을이분형로지스틱분석 (Binary Logistic Analysis) 을사용하여구하였다. 결과임신중체중증가에따른일반적특성 설문지와임상기록을통해조사된연구대상임신부들의현재임신기간, 연령, 교육수준, 월수입, 직업유무, 가족수, 임신빈도, 입덧여부를 Table 2에나타내었다. 조사당시임신부의임신기간은저증가군에서 26.8 ± 4.1주, 적정증가군에서 27.0 ± 4.9 주, 초과증가군에서 26.3 ± 4.2주였으며, 각군간에유의한차이는없었다. 교육수준에서고졸 Table 2. General and obstetrical characteristics of maternals by gestational weight gain category N (%) Under-gain (n = 191) Recommended gain (n = 214) Over-gain (n = 145) Gestational period at baseline (wk) 1) 26.8 ± 4.1 1) 27.0 ± 4.9 26.3 ± 4.2 0.393 2) Age (years) 32.2 ± 4.2 32.2 ± 3.8 31.9 ± 4.0 0.669 Educational year 12 040 (23.5) 030 (16.0) 037 (28.5) 0.026 3) > 12 130 (76.5) 157 (84.0) 093 (71.5) Income level (10,000 won/mo) 200 027 (16.0) 026 (14.1) 027 (21.1) 0.249 > 200 142 (84.0) 159 (85.9) 101 (78.9) Employed status Yes 064 (38.1) 066 (36.1) 44 (34.4) 0.801 No 104 (61.9) 117 (63.9) 84 (65.6) Number of family members (person) 2.9 ± 1.1 2.7 ± 1.0 2.7 ± 0.9 0.051 Pregnancy frequencies 2.3 ± 1.2 2.1 ± 1.2 2.2 ± 1.2 0.266 Morning sickness Yes 73 (48.3) 064 (38.8) 57 (49.1) 0.131 No 78 (51.7) 101 (61.2) 59 (50.9) categories according to the IOM guidelines: see table 1 1) Mean ± SD, 2) by ANOVA, 3) by chi-square test
144 / 임신중체중증가와영양섭취및임신결과 이하는초과증가군에서 28.5% 로가장많았고, 대졸이상은 84.0% 로적정증가군에서가장높았다 (p < 0.05). 임신부의연령, 월수입, 직업유무, 가족수, 임신빈도, 입덧에서는유의한차이가나타나지않았다. 신체계측치연구대상자들의신장, 임신전체중, 임신전 BMI, 분만직전몸무게를 Table 3에나타내었다. 임신부의신장은초과증가군이저증가군과적정증가군보다유의하게 (p < 0.001) 컸다. 임신전체중은초과증가군이저증가군과적정증가군보다높았고 (p = 0.001), 임신전 BMI 는초과증가군이적정증가군보다높았다 (p < 0.05). 분만직전몸무게는저증가군, 적정증가군, 초과증가군순으로높아졌다 (p < 0.001). 흡연, 음주, 커피섭취, 스트레스임신중체중증가와관련하여연구대상자들의건강에영 향을미치는흡연, 음주, 커피섭취, 스트레스를 Table 4에나타내었다. 흡연상태에서흡연을전혀하지않는임신부의비율이저증가군 (96.5%) 에서가장높았고과거에흡연했지만임신후금연을한임신부는초과증가군 (16.1%) 에서가장높았다 (p = 0.001). 본연구에서임신중체중증가에따른알코올섭취, 커피섭취의빈도, 스트레스에서유의한차이는없었다. 다이어트경험및신체활동과운동정도다이어트경험, 신체활동, 운동정도는 Table 5에나타내었다. 임신전다이어트경험이있는임신부는초과증가군에서높은경향을보였지만유의한차이는없었다. 임신중다이어트시도, 신체활동의정도에서도세군간에유의한차이가없었다. 규칙적인운동에서는규칙적인운동을했다고응답한임신부의비율이초과증가군 (28.7%) 에서 Table 3. Anthropometric characteristics of the maternals by gestational weight gain category Under-gain (n = 191) Recommended gain (n = 214) Over-gain (n = 145) Height (cm) 160.6 ± 4.7 a1)2) 161.3 ± 4.6 a 162.6 ± 4.4 b < 0.001 3) Pre-pregnancy weight (kg) 054.3 ± 7.4 a 054.1 ± 8.6 a 057.3 ± 9.1 b < 0.001 Pre-pregnancy BMI (kg/m 2 ) 021.1 ± 2.8 ab 020.8 ± 3.2 a 021.7 ± 3.5 b < 0.030 Full term body weight (kg) 062.7 ± 6.7 a 067.7 ± 7.6 b 076.0 ± 8.0 c < 0.001 categories according to the IOM guidelines: see table 1 1) Mean ± SD 2) Values with different superscripts within the same row are significantly different at p < 0.05 by Tukey test 3) by ANOVA Table 4. Smoking status, alcohol and coffee drinking, stress status of the maternals by gestational weight gain category N (%) Under-gain (n = 191) Recommended gain (n = 214) Over-gain (n = 145) Smoking Non-smoker 164 (96.5) 163 (87.2) 104 (83.9) 0.001 1) Ex-smoker 6 (03.5) 24 (12.8) 20 (16.1) Current-smoker 0 (00.0) 0 (00.0) 0 (00.0) Alcohol drinking Non-drinker 95 (56.2) 117 (62.6) 85 (67.5) 0.234 Ex-drinker 73 (43.2) 70 (37.4) 41 (32.5) Current-drinker 0 (00.0) 1 (00.4) 0 (00.0) Frequency of coffee drinking No 68 (40.5) 76 (40.6) 49 (37.7) 0.116 1-2/wk 54 (32.1) 56 (29.9) 30 (23.1) 3-4/wk 25 (14.9) 41 (21.9) 32 (24.6) > 5/wk 21 (12.5) 14 (07.5) 19 (14.6) Stress 2) Low 130 (76.0) 155 (83.8) 105 (80.2) 0.187 High 41 (24.0) 30 (16.2) 26 (19.8) categories according to the IOM guidelines: see table 1 1) by chi-square test, 2) low < 12, high 12
한국영양학회지 (Korean J Nutr) 2010; 43(2): 141~151 / 145 Table 5. Weight reduction attempt, physical activity and exercise status of the maternals by gestational weight gain category N (%) Under-gain (n = 191) Recommended gain (n = 214) Over-gain (n = 145) 1) Pre-pregnancy weight reduction attempt Yes 027 (18.2) 036 (22.1) 035 (30.4) 0.062 No 121 (81.8) 127 (77.9) 080 (69.6) Weight reduction attempt during pregnancy Yes 004 (02.7) 008 (04.9) 003 (02.6) 0.487 No 142 (97.3) 155 (95.1) 111 (97.4) Physical activity Light 102 (68.9) 110 (68.3) 077 (67.0) 0.997 Moderate 041 (27.7) 045 (28.0) 034 (29.6) Heavy 005 (03.4) 006 (03.7) 004 (03.5) Regular Exercise Yes 025 (16.9) 030 (18.6) 033 (28.7) 0.045 No 123 (83.1) 131 (81.4) 082 (71.3) categories according to the IOM guidelines: see table 1 1) by chi-square test Table 6. Mini dietary assessment scores of the maternals by gestational weight gain category Mini dietary assessment index Under-gain (n = 191) Recommended gain (n = 214) Over-gain (n = 145) Drink milk or eat dairy products once or more a day 1.9 ± 0.8 1) 1.8 ± 0.8 1.7 ± 0.8 0.084 2) Eat meat, fish, egg more than twice a day 2.6 ± 0.6 2.6 ± 0.6 2.5 ± 0.6 0.276 Eat bean, tofu, bean-curd dregs every day 2.7 ± 1.6 b3) 2.4 ± 0.7 a 2.4 ± 0.6 a 0.016 Eat kimchi more than two meals a day 1.9 ± 0.7 b 1.9 ± 0.8 b 1.7 ± 0.7 a 0.046 Eat green leafy vegetables more than two meals a day 2.5 ± 0.6 2.3 ± 0.7 2.4 ± 0.7 0.150 Eat green-yellow vegetables more than two meals a day 2.7 ± 0.6 2.6 ± 0.6 2.6 ± 0.6 0.397 Eat fruit or drink a glass of 100% fruit juice everyday 1.6 ± 0.6 b 1.4 ± 0.6 a 1.6 ± 0.7 b 0.035 Eat much for fried food, broiled food and salad dressing 2.7 ± 0.5 2.7 ± 0.5 2.7 ± 0.5 0.913 Eat much for the fatty meat 2.7 ± 0.5 2.7 ± 0.5 2.7 ± 0.5 0.525 Add table salt or soy sauce to food when dining out 2.9 ± 0.3 2.9 ± 0.2 2.9 ± 0.3 0.769 Take three meals a day regularly 2.1 ± 0.7 2.1 ± 0.8 2.0 ± 0.7 0.203 Have ice-cream, cake, snack, soft drink 2.7 ± 0.5 2.6 ± 0.5 2.6 ± 0.6 0.404 Eat a balanced diet with a variety of foods 2.0 ± 0.6 2.0 ± 0.7 2.0 ± 0.6 0.341 categories according to the IOM guidelines: see table 1 1) Mean ± SD, 2) by ANOVA 3) Values with different superscripts within the same row are significantly different at p < 0.05 by Tukey test 가장높았고저증가군 (16.9%) 에서가장낮았다 (p < 0.05). 식습관점수 Mini-Dietary Assessment 를이용하여평가한임신부의식습관점수는 Table 6과같다. 콩, 두부, 순두부, 비지등콩으로된음식을매일먹는다 에서저증가군이적정증가군보다유의하게높았다 (p < 0.05). 김치를매일두끼이상먹는다 에서는저증가군이초과증가군보다유의하게높았다 (p < 0.05). 과일을 1개이상또는 100% 과일쥬스를 1잔이상매일먹는다 에서는저증가군 1.6 ± 0.6, 적정증가군 1.4 ± 0.6, 초과증가군 1.6 ± 0.7 로적정증가군이가장낮았다 (p < 0.05). 영양소섭취임신중체중증가에따라분류된세군사이에서임신중영양소섭취량의차이가있는지알아본결과는 Table 7과같다. 탄수화물은저증가군이 264.9 ± 60.3 g, 적정증가군이 287.4 ± 75.8 g을섭취하여적정증가군이저증가군보다탄수화물섭취량이유의하게많았다 (p < 0.05). 칼륨은저증가군이 2,881 ± 909.9 mg, 초과증가군이 3,193
146 / 임신중체중증가와영양섭취및임신결과 Table 7. Nutrient intake of the maternals by gestational weight gain category Nutrients Under-gain (n = 130) Recommended gain (n = 145) Over-gain (n = 100) Energy (kcal) 1833 ± 395 1) 1906 ± 4380 1838 ± 4450 0.292 2) Protein (g) 75.3 ± 21.6 77.8 ± 21.8 74.5 ± 20.7 0.454 Fat (g) 55.6 ± 20.6 52.6 ± 19.8 52.0 ± 21.1 0.343 Carbohydrate (g) 0264.9 ± 60.3 a3) 287.4 ± 75.8 b 0 271.8 ± 70.1 ab 0.023 Dietary fiber (g) 21.4 ± 6.90 22.8 ± 7.30 22.1 ± 7.40 0.313 Vitamin A (μgre) 981.2 ± 653.0 914.1 ± 691.7 867.1 ± 414.4 0.366 Vitamin E (mg) 16.9 ± 8.50 16.5 ± 7.70 16.2 ± 7.50 0.829 Vitamin C (mg) 120.8 ± 82.00 130.0 ± 84.80 137.5 ± 80.50 0.310 Niacin (mg) 16.3 ± 5.80 17.3 ± 6.90 16.7 ± 6.00 0.417 Vitamin B1(mg) 1.4 ± 0.5 1.3 ± 0.5 1.3 ± 0.6 0.803 Vitamin B2 (mg) 1.5 ± 1.4 1.3 ± 0.5 1.3 ± 0.5 0.426 Vitamin B6 (mg) 2.2 ± 0.8 2.3 ± 0.7 2.3 ± 0.9 0.437 Folic acid (μg) 273.1 ± 113.0 297.6 ± 129.4 311.1 ± 120.7 0.054 Calcium (mg) 637.2 ± 274.4 674.5 ± 291.2 643.4 ± 284.3 0.509 Phosphorous (mg) 1124 ± 3210 1169 ± 3380 1118 ± 3780 0.417 Sodium (mg) 4386 ± 1640 4534 ± 1568 4576 ± 1666 0.631 Potassium (mg) 2881 ± 910 a 0 0 3144 ± 1076 ab 03193 ± 1054 b 0.036 Iron (mg) 14.9 ± 7.10 15.1 ± 5.30 14.2 ± 5.70 0.508 Zinc (mg) 9.4 ± 4.0 9.3 ± 2.8 9.5 ± 7.6 0.929 Cholesterol (mg) 348.7 ± 202.6 324.1 ± 196.5 325.9 ± 211.8 0.556 categories according to the IOM guidelines: see table 1 1) Mean ± SD, 2) by ANOVA 3) Values with different superscripts within the same row are significantly different at p < 0.05 by Tukey test ± 1,053.6 mg을섭취하여초과증가군이저증가군보다칼륨섭취량이유의하게많았다 (p < 0.05). 엽산의섭취량은저증가군, 적정증가군, 초과증가군순으로높았지만유의한차이는없었다. 열량, 단백질, 지방, 식이섬유, 칼슘, 인, 철분, 나트륨, 아연, 비타민 A, 비타민 B 1, 비타민 B 2, 비타민 B 6, 나이아신, 비타민 C, 비타민 E, 콜레스테롤은각군간에유의한차이가없었다. 한국인영양섭취기준 (KDRIs) 과비교영양소섭취량과한국인영양섭취기준과비교분석한결과는 Table 8에나타내었다. 에너지필요추정량에 75% 미만으로섭취하는비율은저증가군에서 44.6% 로가장높았다. 단백질의경우평균필요량이하로섭취하는비율이초과증가군에서 17.0% 로높았다. 지방을 15% 미만으로섭취하는비율은초과증가군에서높았으며 25% 이상으로섭취하는비율또한초과증가군에서높게나타났다. 탄수화물을 55% 미만으로섭취하는비율은저증가군에서가장높게나타났고 70% 이상으로섭취하는비율은적정증가군에서가장높았다. 대부분의대상자들은비타민 A, 비타민 E, 비타민 C, 나이아신, 비타민 B 6 의섭취를충족시켰지만저 증가군을제외한비타민 B 1, 비타민 B 2, 엽산, 칼슘, 철에서 50% 이상이평균필요량을충족시키지못하였다. 섬유소는충분섭취량을충족시키지못한사람이 80% 정도였다. 임신결과연구대상임신부들과태어난신생아들의임신결과는 Table 9와같다. 임신중체중증가에따른임신기간동안총체중증가량은저증가군 8.45 ± 2.69 kg, 적정증가군 13.53 ± 2.02 kg, 초과증가군 18.62 ± 4.15 kg이었다 (p < 0.001). 임신기간에서저증가군이적정증가군과초과증가군에비해짧았다 (p = 0.001). 조산아와정상아의비율을살펴보면저증가군에서조산아가태어난비율이높았고적정증가군에서정상아가태어난비율이높았지만통계적으로유의하지는않았다. 신생아의출생시체중은저증가군이적정증가군과초과증가군에비해적었다 (p = 0.001). 신생아의출생시체중을비율로살펴보면저체중아가태어난비율은저증가군에서가장높았고정상아가태어난비율은적정증가군에서가장높았으며과체중아가태어난비율은초과증가군에서
한국영양학회지 (Korean J Nutr) 2010; 43(2): 141~151 / 147 가장높았다 (p < 0.05). 신생아들의출생시키는적정증가군이저증가군보다유의하게커임신중체중증가가출생시신생아의신장에도영향을미침을알수있다 (p < 0.05). 임신중체중증가와임신결과와의관련성임신중체중증가권장기준치에따라분류한저증가군, 적정증가군, 초과증가군에서저증가군을기준으로하여조산아, 저체중아, 과체중아가태어날위험도를 Table 10에나 Table 8. Assessment of nutrient intake of the maternals by pre-pregnancy BMI category using dietary reference intakes for Koreans (KDRIs) Nutrients Under-gain (n = 130) Recommended gain (n = 145) Over-gain (n = 100) EER 1) < 75 75-125 > 125 < 75 75-125 > 125 < 75 75-125 > 125 Energy (%) 44.6 55.4 0 38.6 60.0 1.4 41.0 59.0 0 AMDR 2) < 55 55-70 > 70 < 55 55-70 > 70 < 55 55-70 > 70 Carbohydrate 79.2 20.0 0.8 67.6 24.1 8.3 70.0 26.0 4.0 AMDR 2) < 15 15-25 > 25 < 15 15-25 > 25 < 15 15-25 > 25 Fat 16.9 54.6 28.5 20.7 54.5 24.8 30.0 40.0 30.0 < EAR 3) EAR-UL 4) > UL < EAR EAR-UL > UL < EAR EAR-UL > UL Protein 15.4 84.6-10.3 89.7-17.0 83.0 - Vitamin A 14.6 83.9 1.5 23.4 75.2 1.4 15.0 850. 0.0 Vitamin C 40.0 60.0 0.0 30.3 69.7 0.0 31.0 69.0 0.0 Niacin 36.2 63.8 0.0 33.8 66.2 0.0 33.0 67.0 0.0 Vitamin B1 47.7 52.3-55.9 44.1-54.0 46.0 - Vitamin B2 51.5 48.5-54.5 45.5-54.0 46.0 - Vitamin B6 37.7 62.3 0.0 31.0 69.0 0.0 36.0 64.0 0.0 Folic acid 96.9 03.1 0.0 94.5 05.5 0.0 94.0 06.0 0.0 Calcium 75.4 24.6 0.0 71.7 28.3 0.0 78.0 22.0 0.0 Phosphorous 04.6 95.4 0.0 02.1 97.9 0.0 07.0 93.0 0.0 Iron 83.8 15.4 0.8 79.3 20.7 0.0 87.0 12.0 1.0 Zinc 47.7 51.5 0.8 46.9 53.1 0.0 51.0 48.0 1.0 < AI 5) > AI < AI > AI < AI > AI Dietary fiber 86.1 013.9 82.8 017.2 80.0 020.0 Vitamin E 16.9 083.1 19.3 080.7 26.3 073.7 Sodium 00.0 100.0 00.0 100.0 00.0 100.0 Potassium 00.0 100.0 00.0 100.0 00.0 100.0 categories according to the IOM guidelines: see table 1 1) EER: Estimated Energy Requirements, 2) AMDR: Acceptable Macronutrient Distribution Ranges 3) EAR: Estimated Average Requirement, 4) UL: Upper Intake Level, 5) AI: Adequate Intake Table 9. Pregnancy outcomes of the maternals and neonates by gestational weight gain category N (%) Under-gain (n = 191) Recommended gain (n = 214) Over-gain (n = 145) Maternals weight gain during pregnancy (kg) 08.45 ± 2.69 a1)2) 13.53 ± 2.02 b 18.62 ± 4.15 c < 0.001 3) Gestational age (weeks) 37.41 ± 3.63 a 38.32 ± 2.36 b 38.51 ± 2.80 b < 0.001 < 37 049 (26.5) 037 (17.9) 029 (20.1) < 0.105 4) 37 136 (73.5) 170 (82.1) 115 (79.9) Neonates weight (kg) 02.90 ± 0.68 a 03.09 ± 0.60 b 03.15 ± 0.63 b < 0.001 < 2.5 036 (19.8) 030 (14.6) 021 (14.7) < 0.004 2.5-3.99 142 (78.0) 174 (84.5) 111 (77.6) 4 004 (02.2) 002 (01.0) 011 (07.7) Length (cm) 48.09 ± 4.33 a 49.21 ± 3.42 b 049.05 ± 4.20 ab 0<.014 categories according to the IOM guidelines: see table 1 1) Mean ± SD, 2) Values with different superscripts within the same row are significantly different at p < 0.05 by Tukey test 3) by ANOVA, 4) by chi-square test
148 / 임신중체중증가와영양섭취및임신결과 Table 10. Odds ratio (OR) and 95% confidence interval (CI) of preterm delivery, low birth weight (LBW) and macrosomia according to gestational weight gain category IOM guidelines p for trend 1) Under-gain Recommended gain Over-gain Preterm delivery (< 37 weeks) No. of case/control 49/136 37/170 29/115 OR (95% CI) 2) 1 0.54 (0.30-0.98) 0.67 (0.35-1.27) 0.133 LBW (< 2.5 kg) No. of case/control 36/142 30/174 21/111 OR (95% CI) 3) 1 0.73 (0.39-1.38) 0.75 (0.36-1.54) 0.361 Macrosomia (> 4 kg) No. of case/control 4/142 02/174 11/111 OR (95% CI) 3) 1 0.21 (0.02-1.96) 3.06 (0.88-10.63) 0.047 cutoff was categorized as less (Under-gain) than, within (Recommended gain), or greater (Over-gain) than the Institute of Medicine guidelines according to pre-pregnancy BMI (Table 1) 1) test for trend 2) Odds ratio and 95% confidence intervals were analyzed by logistic regression. Odds ratio (OR) was adjusted for maternal height, income 3) Models adjusted for maternal height, income, education 타내었다. 조산의 Odds ratio (OR) 를보기위해산모의신장, 월수입을보정하였고저체중아와과체중아의 Odds ratio (OR) 를보기위해산모의신장, 월수입, 교육수준을보정하였다. 적정증가군에서저증가군보다조산의위험이유의하게감소했다 (0R = 0.54, CI = 0.30-0.98). 임신중체중증가와저체중아와의관련성에서는통계적으로유의한차이는없었으나적정증가군과초과증가군에서저증가군보다저체중아출산위험이낮은경향을보였다. 과체중아가태어날위험은적정증가군에서는줄었지만초과증가군에서는증가하는경향을보였다 (p for trend < 0.05). 고찰 임신중산모의체중증가가임신결과에영향을미친다는연구결과들이보고되었다. 19,20) 본연구에서교육수준을보면고졸이하의비율이초과증가군에서가장높았고, 대졸이상은적정증가군에서가장높아교육수준이높을수록임신중체중이적당하게증가하고교육정도가임신중체중증가에영향을미치는요인이라는보고와일치한다. 21) 신장에서는초과증가군이저증가군과적정증가군보다유의하게컸는데이무식등 22) 의연구에서도체중이증가할수록신장이유의하게더큰것으로나타나산모의신장이임신중체중증가에영향을미치는것으로보인다. 연구대상자들의흡연상태에서흡연을전혀하지않는임신부의비율이저증가군에서높았고과거에흡연했지만임신후금연을한임신부는초과증가군에서높아흡연상태또한임신중체중증가에영향을미치는것으로보인다. 커피섭취의빈도에서는유의한차이가없었는데서혜진과양영옥 23) 은카페인을섭취한산모들의체중증가량이섭취하지않은산모들보다적었다는보고가있어카페인이임신중체중증가에영향을미치는것으로보여카페인과디카페인이구별된연구가더필요한것으로보인다. 규칙적인운동에서는규칙적인운동을했다고응답한임신부의비율이초과증가군에서가장높아초과증가군에서몸무게감소를위한시도를한것으로보인다. 임신중운동은분만시간단축과진통의경감, 출산후빠른회복, 스트레스완화에효과가있고과도한체중증가를감소시키므로 24) 규칙적이고적당한강도의운동을권장한다. 식습관은장기간에걸쳐형성되기때문에단기간에변화시키기는어렵지만식품선택과기호도에영향을주어영양섭취상태에영향을미치고건강상태를결정하게되므로 25) 임신부에게올바른식습관이요구된다. 하지만임신부를대상으로한연구는체중증가나특정영양소에초점을두고있어바람직한식습관에대해서연구된것은드물다는지적이있다. 26) 국내에서임신중체중증가에따른식습관과영양소를살펴본연구도드물어임신중체중증가에따른식습관점수와영양소에대한분석은의미가있다. 임신중체중증가에따른식습관점수중 콩, 두부, 순두부, 비지등콩으로된음식을매일먹는다 에서는저증가군이적정증가군보다유의하게높았는데단백질은태아, 태반, 모체조직의합성과유지에요구되어져임신으로인한단백질의필요량은증가함으로 27) 콩류, 두부류의섭취가권장된다. 김치를매일두끼이상먹는다 에서는저증가군이초과증가군보다유의하게높았는데김치에는비헴
한국영양학회지 (Korean J Nutr) 2010; 43(2): 141~151 / 149 성철분의흡수이용률을높이는성분들이들어있어철분의흡수에도움을줄것이라고보고되었다. 28) 과일을 1개이상또는 100% 과일쥬스를 1잔이상매일먹는다 에서는초과증가군에서유의하게높았는데과일은비타민과무기질의급원식품으로서특히오렌지쥬스는 100 μg 의엽산을함유하여비타민 C뿐아니라상당량의엽산도같이섭취하게되므로임신부에게좋은급원식품이된다. 29) 임신기간동안의영양은임신부와태아의건강뿐만아니라출산후여성의중년기, 노년기까지영향을주게되므로중요하다. 30) 열량은필요추정량의 75~125% 인적정범위에해당되는비율이세군모두 50% 가조금넘는비율이므로태아, 태반, 양수등새로운조직형성과유방이나자궁과같은임신부조직의성장과임신부의지방축적을 위해 31) 임신중반기에약 340 kcal/day 를추가할것을권 장한다. 18) 탄수화물의섭취는적정증가군이저증가군보다유의하게높았는데탄수화물은지질, 단백질과함께주요에너지원으로사용되므로태아와임신부의건강을위해탄수화물, 지질, 단백질의에너지적정비율에맞추어섭취할것을권장한다. 엽산은평균필요량과비교할때세군모두매우부족한섭취를하고있는것으로나타났다. 하지만많은임신부들이임신기간동안엽산보충제를섭취하고있는실정이므로본연구에서영양소섭취량분석에영양보충제의함량이포함되지않은것이제한점이라고사료된다. 엽산결핍은거대적아구성빈혈을일으키고 32) 신생아의신경관결함빈도를높이는것으로보고되어 33) 엽산영양섭취기준이증가하는임신중에는엽산보충제가필요한것으로사료된다. 칼슘또한세군모두부족한섭취를하고있으므로우유및유제품, 칼슘강화오렌지쥬스의섭취빈도증가와보충제의사용이권장된다. 본연구에서나트륨섭취를보면세군모두 4,000 mg 이상을섭취하고있는것으로나타났는데나트륨은젓갈류, 장아찌, 간고등어등의염장식품을비롯하여간장, 된장, 고추장, 김치에많이함유되어있어일상적으로섭취하게됨으로써과잉섭취되기쉬우므로고혈압, 부종, 임신중독증의발생을예방하기위해 2,000 mg 이하로섭취하는것이바람직하다. 34) 철분은세군모두평균필요량에비교할때부족하게섭취하고있었는데임신시철분섭취의부족으로인한빈혈은면역기전에영향을주어감염에대한저항력을낮추고, 미숙아및저체중아출산의위험이높아져분만시산모와태아의사망위험도증가하게되므로 35) 중요하다. 하지만우리나라임신부의식이를통한철분의섭취는부족하고 36) 철분결핍성빈혈이다른형태의빈혈에비 해빈도가높다. 37) 본연구는철분영양보충제의함량이포함되지않아정확한판단이어려우나식사만으로는철분섭취가부족한것으로보여보충제의복용이필요한것으로보인다. 임신기간에서저증가군이다른군에비해짧아임신기간중체중증가가임신기간에영향을미치는요인으로확인되었고임신중저체중증가가조산의위험을높인다는연구결과가재확인되었다. 7,8) 신생아의출생시체중에서저체중아가태어난비율은저증가군에서가장높았고과체중아가태어난비율은초과증가군에서가장높아임신중체중증가량이적을경우에저체중아를출산할위험이높아지는반면, 많을경우에과체중아를출산할위험이높아진다는연구결과와일치한다. 22,38) 신생아들의출생시키는적정증가군이저증가군보다유의하게커임신중체중증가가출생시신생아의신장에도영향을미침을알수있다. 적정증가군이저증가군보다조산의위험이유의하게감소했는데 (OR = 0.54, CI = 0.30-0.98) Koh & Park 39) 의연구에서도저증가군일때는조산의위험도가증가 (OR = 3.23, CI = 2.16-4.84) 했지만적정증가군 (OR = 0.47, CI = 0.31-0.64) 과초과증가군 (OR = 0.29, CI = 0.13-0.64) 에서는조산의위험률이감소함을보였다. 과체중아가태어날위험은정상증가군에서는줄었지만초과증가군에서는증가하는경향을보였다 (p for trend < 0.05). Frederick 등 38) 의연구에서는임신중체중증가가중위수보다적으면저체중아의위험률이 2배증가 (RR = 2.04, CI = 1.34-3.11) 한다고하였고임신중체중증가량이커질수록과체중아의위험률도증가한다고보고하였다 ( p for trend < 0.001). 산모의임신전 BMI 에따른임신중체중증가가임신결과에영향을미쳐임신중체중증가가적을때는임신기간이짧았고출생시저체중아가태어날위험도높아졌으며체중증가가많을때는과체중아가태어날위험이높아졌다. 따라서임신전 BMI 에따른적정체중증가량에맞추어마른체형의산모는체중증가의정도를더늘리고뚱뚱한체형의산모는체중증가의정도를줄이도록하는산전관리가필요한것으로사료된다. 또한임신중섭취량을늘려야하는영양소중에서에너지, 식이섬유, 엽산, 칼슘, 철의섭취가임신부의영양섭취기준에못미치는수준이었고, 나트륨같은경우는세군모두 4,000 mg이넘게섭취하고있었는데균형잡힌영양소는산모와태아의건강을위해반드시필요하므로임신가능한여성과임신부에게올바른식습관과균형있는식사를하도록사전에교육함으로써산모와태아의건강을지키도록하는노력이필요하다.
150 / 임신중체중증가와영양섭취및임신결과 요약및결론 임신전 BMI 에따른체중증가를미국의 Institute of Medicine (2009) 의 guideline 을근거로하여세군으로분류해우리나라임신부를대상으로임신전 BMI 와임신중체중증가에따른임신부의영양상태와임신기간및신생아체중과의관련성을알아보았다. 연구결과를요약하면다음과같다. 1) 연령, 월수입, 직업유무, 가족수, 임신빈도, 입덧여부는각군간에유의한차이가없었다. 교육수준에서고졸이하는초과증가군에서가장많았고, 대졸이상은적정증가군에서가장높았다 (p < 0.05). 임신부의신장 (p < 0.001) 과임신전몸무게 (p = 0.001) 는초과증가군이다른군에비해유의하게컸다. 2) 흡연상태를보면흡연을전혀하지않는임신부의비율이저증가군에서가장높았고과거에흡연했지만임신후금연을한임신부는초과증가군에서가장높았다 (p = 0.001). 3) 규칙적인운동을한임신부들의비율은초과증가군에서가장높았고저증가군에서가장낮았다 (p < 0.05). 4) 콩류를먹는식습관점수에서저증가군이적정증가군보다유의하게 (p < 0.05) 높았고, 김치에서는저증가군이초과증가군보다유의하게 (p < 0.05) 높았다. 과일에서는초과증가군의점수가유의하게 (p < 0.05) 높았다. 영양소섭취에서탄수화물의섭취량이적정증가군이저증가군보다유의하게 (p < 0.05) 많았고, 칼륨은초과증가군이저증가군보다섭취량이유의하게 (p < 0.05) 많았다. 5) 임신기간은저증가군이다른군보다짧았고 (p = 0.001), 신생아의출생시체중도저증가군이다른군에비해적었다 (p = 0.001). 신생아의출생시체중을비율로살펴보면저체중아가태어난비율은저증가군에서가장높고과체중아가태어난비율은초과증가군에서가장높았다 (p < 0.05). 신생아들의출생시키는적정증가군이저증가군보다유의하게 (p < 0.05) 컸다. 6) 임신중체중증가와조산과의관련성을보면적정증가군이저증가군보다조산의위험이유의하게 (OR = 0.54, CI = 0.30-0.98) 감소했다. 임신중체중증가와저체중아와의관련성에서는통계적으로유의한차이는없었으나적정증가군과초과증가군이저증가군보다저체중아분만위험이낮은경향을보였다. 과체중아가태어날위험은정상증가군에서는줄었지만초과증가군에서는증가하는경향을보였다 (p for trend < 0.05). 본연구에서임신중체중증가가적은저증가군에서다른군에비해임신기간이짧고저체중아의출생비율이높았고초과증가군에서과체중아의출생비율이높았으며신생아의출생키에도영향을미치므로임신전 BMI 에따른적정체중증가량에맞추어마른체형의산모는체중증가의정도를더늘리고뚱뚱한체형의산모는체중증가의정도를줄이도록하는산전관리가필요한것으로사료된다. Literature cited 1) Berenson AB, Wiemann CM, Rowe TF, Rickert VI. Inadequate weight gain among pregnant adolescents: risk factors and relationship to infant birth weight. Am J Obstet Gynecol 1997; 176 (6): 1220-1227 2) Godfrey KM, Barker DJ. Fetal nutrition and adult disease. Am J Clin Nutr 2000; 71(5): 1344s-1352s 3) Korean statistical information service. Population trend survey, Seoul; 2008 4) World Health Organization. WHO: Recommended definitions, terminology and format for statistical tables related to the perinatal period and use of a new certificate for cause of perinatal deaths. Modifications recommended by FIGO as amended October 14, 1976. Acta Obstet Gynecol Scand 1977; 56(3): 247-253 5) Johnson JW. Obstetric aspects of preterm delivery. Clin Obstet Gynecol 1980; 23(1): 15-16 6) Koo YH, Kim SK, Shim JY, Won HS, Lee PR, Kim A. Analysis of preterm birth rate based on birth certificate data: from 1995 to 2003. Korean J Obstet Gynecol 2006; 49(9): 1855-1865 7) Abrams B, Newman V, Key T, Parker J. Maternal weight gain and preterm delivery. Obstet Gynecol 1989; 74(4): 577-583 8) Hediger ML, Scholl TO, Belsky DH, Ances IG, Salmon RW. Patterns of weight gain in adolescent pregnancy: effects on birth weight and preterm delivery. Obstet Gynecol 1989; 74(1): 6-12 9) Nohr EA, Bech BH, Vaeth M, Rasmussen KM, Henriksen TB, Olsen J. Obesity, gestational weight gain and preterm birth: a study within the Danish National Birth Cohort. Paediatr Perinat Epidemiol 2007; 21(1): 5-14 10) Dietz PM, Callaghan WM, Cogswell ME, Morrow B, Ferre C, Schieve LA. Combined effects of prepregnancy body mass index and weight gain during pregnancy on the risk of preterm delivery. Epidemiology 2006; 17(2): 170-177 11) Fortner RT, Pekow P, Solomon CG, Markenson G, Chasan-Taber L. Prepregnancy body mass index, gestational weight gain, and risk of hypertensive pregnancy among Latina women. Am J Obstet Gynecol 2009; 200(2): 167.e1-167. e7 12) Chen Z, Du J, Shao L, Zheng L, Wu M, Ai M, Zhang Y. Prepregnancy body mass index, gestational weight gain, and pregnancy outcomes in China. Int J Gynaecol Obstet 2009 Dec 15. [Epub ahead of print] 13) Kabali C, Werler MM. Pre-pregnant body mass index, weight gain and the risk of delivering large babies among non-diabetic mothers. Int J Gynecol Obstet 2007; 97(2): 100-104 14) IOM (Institute of Medicine). Weight gain during pregnancy: Re-
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