不同季节112例母婴维生素D营养状况分析

目的 以血清25-(OH)D为检测指标, 了解不同季节、不同居住环境孕妇及其新生儿的维生素D营养状况及母婴血清维生素D的相关性。方法 选取冬季(2010年12月-2011年2月)和夏季(2011年6月-2011年8月)在河北北方学院附属第二医院妇产科正常分娩的孕妇及其新生儿为研究对象。72对孕妇及其新生儿为冬季组, 40对孕妇及其新生儿为夏季组。孕妇于分娩前采集静脉血, 新生儿于娩出后采集脐血, 分离血清。酶联免疫法测定血清25-(OH)D水平。维生素D营养状况采用三分法:1)维生素D缺乏:25-(OH)D＜50 nmol/L;2)维生素D不足:50 nmol/L≤25-(OH)D＜75 nmol/L;3)维生素D充足:25-(OH)D≥75 nmol/L。结果 1)冬季和夏季孕妇血清25-(OH)D水平分别为(19.48±7.04)nmol/L和(53.15±17.50)nmol/L, 冬季显著低于夏季;对应的新生儿脐血25-(OH)D水平分别为(19.95±6.79)nmol/L和(47.39±15.31)nmol/L, 冬季显著低于夏季。2)冬季孕妇25-(OH)D水平为9.19~36.99 nmol/L, 新生儿25-(OH)D水平为7.78~37.36 nmol/L, 冬季孕妇及新生儿维生素D缺乏率为100%。夏季孕妇25-(OH)D水平为26.72~103.90 nmol/L, 新生儿25-(OH)D水平为20.76~79.91 nmol/L, 夏季孕妇和新生儿维生素D缺乏率分别为47.5%和62.5%。3)孕妇与新生儿25-(OH)D水平具有显著正相关(r=0.902)。4)冬季组孕妇及其新生儿25-(OH)D水平无城乡之间的差异;夏季组孕妇及其新生儿25-(OH)D水平存在城乡之间的差异, 农村孕妇及其新生儿25-(OH)D水平高于城市。结论 孕妇及其新生儿25-(OH)D水平存在明显的季节差异。冬季孕妇及其新生儿普遍维生素D缺乏, 即使夏季孕妇及其新生儿维生素D缺乏比率也较高。     

血清25-羟维生素D水平对妊娠妇女细菌性阴道病发生率的影响

目的探讨妊娠中、晚期血清25-羟维生素D[25(OH)D]水平对细菌性阴道病(BV)发生率的影响。方法对2013~2014年在我院进行产检的300例孕妇孕期在14~23周及24~28周的孕妇进行血清25(OH)D检测并取阴道分泌物进行BV检查,描述性统计分析25(OH)D缺乏[25(OH)D≤50.0 nmol/L]、不足[50.0 nmol/L<25(OH)D≤75.0 nmol/L]和正常[25(OH)D>75.0 nmol/L]三类孕妇的百分构成及其相应的细菌性阴道病(BV)发生率,并应用2检验比较分析其显著性水平。结果 1在孕中期妇女中,25(OH)D缺乏、不足和正常者分别占53.00%(159/300)、30.70%(92/300)和16.30%(49/300),其相对应的BV的发生率分别为42.13%(67/159)、31.50%(28/92)、8.20%(4/49);在孕晚期妇女中,25(OH)D缺乏、不足和正常者分别占69.00%(207/300)、27.00%(81/300)和4.00%(12/300),其相对应的BV的发生率分别为48.80%(101/207)、39.50%(32/81)、8.33%(1/12)。2比较分析发现:妊娠晚期比中期孕妇25(OH)D水平明显下降,相对应的BV感染率明显升高,妊娠中、晚期25(OH)D不足和缺乏组孕妇的BV发生率显著高于正常组。结论妊娠妇女随着妊娠期的延续,25(OH)D缺乏程度不断加重,BV发生率与25(OH)D缺乏程度呈正相关,在孕期中必须注意补充适量的维生素D。     

早产儿维生素D水平及影响因素分析

目的 探讨早产儿维生素D水平及可能的影响因素。方法 选取2021年3月-2022年8月本科新生儿病区收治的94例早产儿为研究对象,采集其出生后24h内的静脉血完善血清25羟基维生素D[25(OH)D]水平测定,并分析母亲年龄、孕前体重指数（BMI）、孕期体重增值、孕期日晒时间、受孕方式、职业、学历、分娩方式、分娩季节、胎数、妊娠期合并/并发症、孕期补充维生素D情况以及早产儿胎龄、性别等因素对早产儿25(OH)D水平的影响。结果 早产儿25(OH)D水平为（55.50±27.62）nmol/L;维生素D缺乏、不足及充足的比例分别为16.0%、27.7%、56.3%;早产儿维生素D缺乏和不足与母亲孕期日晒时间<30min/d、职业、孕期不规律或未补充维生素D以及受孕方式几个因素相关（P<0.05）。多因素分析显示：母亲孕期日晒时间<30min/d及孕期不规律补充或未补充维生素D是早产儿维生素D缺乏和不足的危险因素（P<0.05）。结论 早产儿25(OH)D水平为（55.50±27.62）nmol/L,总体来说早产儿维生素D营养状态较理想,对母亲孕期日晒时间较短及补充...     

南京某医院妊娠中晚期孕妇维生素D水平及影响因素

目的　了解南京地区妊娠中晚期孕妇维生素D水平,并分析其与年龄、孕周、孕前体质量指数（BMI）以及季节变化之间的关系,为临床开展维生素D检测及补充提供依据。方法　收集2015年1至12月在南京医科大学附属妇产医院建卡并定期产检的880名妊娠21~36周孕妇为研究对象,酶联免疫吸附法（ELISA）测定血清25羟-维生素D［25-（OH）D］浓度。结果　孕妇血清维生素D水平为（42.03±19.22）nmol/L,维生素D充足者仅42例（4.77%）。季节变化对维生素D水平有影响（P=0.016 4）,夏季 ［（44.61±23.57）nmol/L］和秋季［（43.43±19.31）nmol/L］高于春季［（39.68±16.91）nmol/L］和冬季［（39.65±13.36）nmol/L］（均P＜0.05）。不同孕周间血清维生素D水平差异无统计学意义（P=0.929 4）。不同年龄组间孕妇血清维生素D水平差异有统计学意义（P=0.038 3）。维生素D和孕前BMI间无相关性。结论　维生素D作为孕妇以及胎儿生长发育的必要营养素,营养状况不容乐观,建议积极开展维生素D检测。     

阿尔茨海默病与维生素D水平的关系

目的,了解阿尔茨海默病（AD）患者体内维生素D营养状况,分析其血清25羟维生素D[25(OH)D ]水平与认知功能的关系,为临床补充维生素D制剂的干预研究提供依据。方法 回顾性分析本院113例住院AD患者血清总25(OH)D浓度与认知功能的关系。采用液相色谱-串联质谱法（LC-MS／MS）,定量测定AD患者血清25(OH)D2、25(OH)D3 和总25(OH)D浓度。按2011年美国医学科学院(IOM)的维生素D营养状况分级标准分组：维生素D充足组［25(OH)D≥75 nmol/L］、维生素D不足组［25(OH)D 50～75 nmol/L］、维生素D缺乏组［25(OH)D 25～50 nmol/L］和维生素D严重缺乏组［25(OH)D≤25 nmol/L］。结果 （1）113例AD患者血清总25(OH)D为（27.08±15.33）nmol/L,其中血清25(OH)D2为（1.23±0.93）nmol/L和25(OH)D3为（24.50±13.04）nmol/L;（2）60.18 %（68/113）患者维生素D严重缺乏、30.97 %（35/113）患者维生素D缺乏、7.97%（9/113）患者维生素D不足和0.88%（1/113）患者维生素D充足;（3）AD患者血清总25(OH)D浓度与MMSE总分的Spearman秩和相关分析呈正相关关系（r=0.202,P=0.032）。结论 住院AD患者严重缺乏维生素D,需要补充维生素D;血清总25(OH)D浓度与认知功能有正相关关系;补充维生素D制剂是否能提高认知功能,需要进一步进行随机双盲、安慰剂对照临床研究证实。     

母孕期维生素D水平与婴儿体格生长的相关性研究

目的 探讨母孕期维生素D水平与婴儿体格生长的相关性。方法 检测孕晚期孕妇血清和新生儿脐血的25-(OH)D;并测量出生时、3、6、8月龄婴儿的体格生长指标及3、6、8月龄胫骨超声骨强度。结果 223例孕母血清25-(OH)D水平为(50.7±18.5)nmol/L,与婴儿体格生长指标无相关性;孕母与新生儿25-(OH)D水平呈正相关,并存在季节差异。结论 孕期维生素D水平与婴儿体格生长无相关性。     

维生素D对冬季母乳喂养婴儿血清25-羟维生素D水平的影响

目的 了解常规口服鱼肝油对纯母乳喂养婴儿冬季血清25-羟维生素D［25(OH)D］水平的影响。方法 采用自身对照方法,于2009年12月至2010年2月,以首都儿科研究所附属儿童医院各项检查正常孕妇分娩的新生儿为对象,取脐带血2 ml,分离血清。新生儿自出生后第15天开始补充鱼肝油,随访至4个月,采集纯母乳喂养婴儿的空腹静脉血2 ml,分离血清,与脐带血清同时检测25(OH)D。结果 共43例纯母乳喂养婴儿,其中男26例,女17例。脐带血清25(OH)D为（20.9±5.1）nmol/L（12.5~32.1 nmol/L）,维生素D缺乏率为100%。第4个月婴儿静脉血清25(OH)D为（106.3±42.4）nmol/L（30.2~208.5 nmol/L）,其中4例＜50 nmol/L（维生素D缺乏率9.3%）,7例50~75 nmol/L,25例75~150 nmol/L,7例＞150 nmol/L。血清25(OH)D水平与口服鱼肝油量呈正相关（r=0.530,P=0.001）。鱼肝油漏服率（漏服时间/应服时间）平均为36.1%（39/108）,血清25(OH)D与漏服时间呈负相关（r=-0.634,P=0.001）。结论 北方冬季新生儿普遍存在维生素D缺乏,母乳喂养婴儿每日口服鱼肝油可显著提高血清25(OH)D水平,但漏服不能确保婴儿免于维生素D缺乏。     

脐血维生素D水平测定及相关因素分析

【目的】了解南京地区脐血维生素D水平,探讨影响脐血维生素D的因素。【方法】选取2008年12月—2009年2月在南京出生的足月新生儿102例,记录其出生时的基本情况,采用酶联免疫法测定脐血及部分孕母静脉血25-(OH)D水平,调查孕母在孕后期的维生素D和钙的补充情况。【结果】脐血25-(OH)D水平为(44.34±17.10)nmol/L,以25-(OH)D30 nmol/L为维生素D缺乏的界值,16例小于该值,占15.7%;30例孕母静脉血25-(OH)D水平为(39.25±15.14)nmol/L,对应的新生儿脐血25-(OH)D为(37.76±12.15)nmol/L,两者呈显著正相关(r=0.842,P0.001)。孕后期补充维生素D和含维生素D孕妇奶粉大于3个月组,脐血25-(OH)D水平显著高于未补充和补充小于3个月组(P0.05)。【结论】南京地区脐血维生素D水平高于发展中国家但低于发达国家;孕母维生素D营养状况决定脐血维生素D水平;孕期补充维生素D和含维生素D的孕妇奶粉有助于提高脐血25-(OH)D水平。     

冬季妊娠中期孕妇25-羟维生素D的营养状况

目的 探讨冬季妊娠中期孕妇的25-羟维生素D[25(OH)D]营养状况及其与孕妇年龄、血红蛋白水平的相关关系。方法 选取2009年12月至2010年2月在南京医科大学第一附属医院就诊的78名正常妊娠中期孕妇为研究对象。于孕24 ～ 28周取空腹静脉血,检测血清25(0H)D和全血血红蛋白水平。采用Pearson相关分析研究血清25(OH)D水平与孕妇年龄、血红蛋白水平的相关性。结果 冬季妊娠中期孕妇25(OH)D缺乏(≤25.0 nmol/L)的发生率为65.38％,25(OH)D不足[25.0 nmol/L＜25 (OH)D≤50.0 nmol/L]的发生率为30.77％,25(OH)D正常者占3.85％。冬季妊娠中期孕妇血清25(OH)D水平与血红蛋白水平呈正相关(r=0.2746,P=0.015)。结论 冬季妊娠中期孕妇普遍存在25(OH)D不足或缺乏,低血红蛋白水平的孕妇尤甚。     

脐血维生素D与婴儿维生素D水平的相关性分析

目的了解新生儿脐血维生素D与婴儿维生素D水平及其相关性。方法收集340名新生儿脐血及与其配对的9个月婴儿血,采用酶联免疫法检测新生儿脐血及婴儿血的血清25（0H）D水平。通过问卷调查收集婴儿喂养方式、母乳喂养的时间、添加维生素D的时间、剂量、户外活动时间等资料;并采用直线相关分析、单因素方差分析及Y。检验等进行新生儿脐血与婴儿血清维生素D水平相关性分析等。结果新生儿脐血和婴儿的25-（0H）D水平分别是（30．03±11．24）nmol／L、（79．05±28．96）nmol／L;92．94％的新生儿和9．71％的9个月婴儿的25～（OH）D水平低于50nmol／L,33．82％的新生儿25-（OH）D水平低于25nmol／L,9个月婴儿的25-（0H）D水平无一例低于25nmol／L。新生儿脐血与9个月婴儿血清25-（0H）D水平无相关性,spearman相关系数r=0．036,P-0．504。新生儿脐血及9个月婴儿血清的25-（OH）D水平均存在明显季节性差异（F分别-20．845,3．565;P分别为0．000,0．014）。维生素D水平在秋季最高,春季最低。结论新生儿脐血维生素D缺乏或不足普遍存在,尤其在春季。婴儿维生素D水平相对较高,尤其是在秋季。新生儿脐血与9个月婴儿血清25-（OH）D水平无相关性。提示婴幼儿维生素D缺乏可防可控,只要合理及时的补充维生素D,即可以有效的预防。必须加强妇幼保健工作管理,重视孕期维生素D的补充;冬春季节的孕妇（尤其是孕晚期）和新生儿以及婴儿应该多参加户外活动,特别重视维生素D的补充。     

Prevalence and Predictors of Vitamin D Deficiency and Insufficiency among Pregnant Rural Women in Bangladesh

Although adequate vitamin D status during pregnancy is essential for maternal health and to prevent adverse pregnancy outcomes, limited data exist on vitamin D status and associated risk factors in pregnant rural Bangladeshi women. This study determined the prevalence of vitamin D deficiency and insufficiency, and identified associated risk factors, among these women. A total of 515 pregnant women from rural Bangladesh, gestational age ≤ 20 weeks, participated in this cross-sectional study. A separate logistic regression analysis was applied to determine the risk factors of vitamin D deficiency and insufficiency. Overall, 17.3% of the pregnant women had vitamin D deficiency [serum 25(OH)D concentration <30.0 nmol/L], and 47.2% had vitamin D insufficiency [serum 25(OH)D concentration between 30–<50 nmol/L]. The risk of vitamin D insufficiency was significantly higher among nulliparous pregnant women (OR: 2.72; 95% CI: 1.75–4.23), those in their first trimester (OR: 2.68; 95% CI: 1.39–5.19), anaemic women (OR: 1.53; 95% CI: 0.99–2.35; p = 0.056) and women whose husbands are farmers (OR: 2.06; 95% CI: 1.22–3.50). The risk of vitamin deficiency was significantly higher among younger pregnant women (<25 years; OR: 2.12; 95% CI: 1.06–4.21), nulliparous women (OR: 2.65; 95% CI: 1.34–5.25), women in their first trimester (OR: 2.55; 95% CI: 1.12–5.79) and those with sub-optimal vitamin A status (OR: 2.30; 95% CI: 1.28–4.11). In conclusion, hypovitaminosis D is highly prevalent among pregnant rural Bangladeshi women. Parity and gestational age are the common risk factors of vitamin D deficiency and insufficiency. A husband’s occupation and anaemia status might be important predictors of vitamin D insufficiency, while younger age and sub-optimal vitamin A status are risk factors for vitamin D deficiency in this population.     

High Prevalence of Vitamin D Deficiency among Pregnant Saudi Women

Vitamin D deficiency has emerged as a public health problem worldwide due to its important role in health and disease. The present work is intended to examine prevalence of vitamin D deficiency among pregnant Saudi women and related risk factors. A cross-sectional study was carried out at King Fahad Medical City in Riyadh, Saudi Arabia. Serum 25-hydroxy vitamin D (25(OH)D) was measured by enzyme-linked immunosorbent assay in 160 pregnant women during the first trimester of pregnancy. Socio-demographic, lifestyle and maternal characteristics were collected and vitamin D intake was assessed using a 24-h dietary recall. Weight and height were measured using standardized methods. Vitamin D deficiency (25(OH)D < 50 nmol/L) and insufficiency (25(OH)D = 50–74 nmol/L) were reported in 50% and 43.8% of the study sample, respectively. Median serum 25(OH)D concentration was 49.9 nmol/L. Adequate vitamin D intake (≥600 IU/day) was reported among only 8.1% of pregnant women. Age group, educational level, sun exposure frequency and daytime and daily practice of exercise were significantly associated with vitamin D status. Overall, vitamin D deficiency was common among pregnant Saudi women in Riyadh. Steps should be taken to address the current situation, including increased sunlight exposure, consumption of fatty fish, and vitamin D supplements.     

421例早中期妊娠孕妇血清中维生素D及微量元素水平分析

目的 分析早中期妊娠孕妇血清中维生素D及微量元素水平。方法 回顾性分析2016年2月—2017年11月于某妇幼保健所进行产前检查的421例孕妇临床资料,孕早期组271例,孕中期组150例。抽取两组孕妇空腹肘静脉血,采用酶联免疫吸附法检测血清25-羟基维生素D水平,采用全自动生化分析仪检测血清微量元素含量。比较两组孕妇维生素D及微量元素水平、维生素D摄入状况。结果 孕早期女性维生素D(27.57±6.23)nmol/L及钙水平为(1.62±0.18)nmol/L,均低于孕中期(28.25±6.07)nmol/L、(1.63±0.16)nmol/L,血清镁水平为(1.49±0.25)nmol/L、铁水平为(7.87±0.37)nmol/L,均高于孕中期(1.39±0.27)nmol/L、(7.79±0.41)nmol/L,差异有统计学意义(P<0.05);孕早期维生素D缺乏率为24.72%,高于孕中期15.33%,孕中期维生素D摄入不足率为70.00%,高于孕早期59.04%,差异有统计学意义(P<0.05)。结论 与孕中期孕妇相比,孕早期孕妇维生素D缺乏现象较为严重,而微量元素水平基本一致。     

西安地区新生儿维生素D水平及影响因素分析

目的调查西安地区(北纬34°)新生儿维生素D水平,并分析其影响因素。方法选取2018年10月至2019年10月在西安交通大学第一附属医院新生儿科住院,生后48小时内入院且生命体征平稳的161例新生儿为研究对象。检测新生儿生后48小时内血清25-羟维生素D[25(OH)D]水平,并分析性别、胎龄、出生季节,母亲年龄、分娩方式、妊娠胎数,以及母亲孕晚期维生素D补充剂量对新生儿血清25(OH)D水平的影响。结果新生儿血清25(OH)D平均水平为12.20(9.10,17.30)ng/mL,维生素D缺乏、不足和充足的发生率分别为65.84%、15.53%和18.63%。单胎新生儿血清25(OH)D水平显著高于双胎新生儿(Z=-1.967,P<0.05)。秋季出生的新生儿血清25(OH)D水平显著高于春季出生的新生儿(H=-2.726,P<0.05)。与母亲孕晚期补充维生素D剂量<600IU/d相比,母亲孕晚期补充维生素D剂量≥600IU/d新生儿血清25(OH)D水平显著增高(Z=-3.968,P<0.05),维生素D缺乏发生率显著降低(χ^2=8.003,P<0.017)。经Logistic回归分析显示,母亲孕晚期补充维生素D剂量<600IU/d是新生儿维生素D缺乏的危险因素(OR=2.481,95%CI:1.023~6.008,P<0.001)。结论西安地区新生儿维生素D缺乏发生率较高;胎数、出生季节和母亲孕期维生素D补充剂量是新生儿维生素D水平的影响因素。     

Maternal Vitamin D Status and Its Associated Environmental Factors: A Cross-Sectional Study

BackgroundVitamin D deficiency is common among women during pregnancy. This study aims to determine the prevalence of vitamin D deficiency and their shared modifiable environmental factors among pregnant women in Indonesia and Malaysia.MethodsBlood samples of 844 third-trimester pregnant women (Indonesians: 311; Malaysians: 533) were collected to determine their serum 25(OH) D levels. Information on sun exposure and sun protection behaviours were obtained through face-to-face interviews. Dietary vitamin D intake was assessed by using a semiquantitative food frequency questionnaire.ResultsThe prevalence of vitamin D deficiency (<30 nmol/L) among Indonesian and Malaysian pregnant women were 42.4% and 72.0%, respectively. Percentage of exposed body surface area was inversely associated with vitamin D deficiency among Indonesian pregnant women (OR = 0.21, 95% CI = 0.09–0.48). Among Malaysian pregnant women, higher intakes of dietary vitamin D were associated with lower risk of vitamin D deficiency (OR = 0.48, 95% CI = 0.29–0.81). Analysis of the combined cohorts revealed a lower risk of vitamin D deficiency among pregnant women who had a daily intake of at least 15 mcg vitamin D (OR = 0.58, 95% CI = 0.38–0.88) and exposure of more than 27% body surface area to the sunlight (OR = 0.30, 95% CI = 0.16–0.60).ConclusionsDespite abundant sunshine, vitamin D deficiency is prevalent among pregnant women in tropical countries. The present study suggests that nutrition education on vitamin D intake and sun exposure during pregnancy is necessary for primary prevention of vitamin D deficiency in pregnant women living in the tropical countries.     

扬州地区新生儿维生素D水平及影响因素研究

目的 了解扬州地区新生儿血清中维生素D（Vitamin D,VD）水平及其影响因素。方法 选取孕早期在扬州市妇幼保健院建卡且于2014年5月~2015年5月在产科住院分娩的孕妇作为初始研究对象。按照纳入和排除标准选入3 913例健康单胎活产新生儿进入此次研究,并通过自制的问卷收集孕妇及新生儿相关信息。采用酶联免疫吸附法检测孕妇及新生儿血清中的VD浓度,描述并分析新生儿VD的分布特征及影响因素。结果 扬州地区新生儿VD水平为（28.79±8.37）nmol/L,其充足率、不足率、缺乏率分别为2.2%、11.7%、86.1%。多因素Logistic回归模型分析结果显示,孕妇孕中期VD缺乏（OR=3.16,95%CI:2.00~5.00,P<0.001）和不足（OR=1.67,95%CI:1.04~2.67,P=0.033）,孕晚期VD缺乏（OR=8.64,95%CI:5.64~13.24,P<0.001）和不足（OR=1.63,95%CI:1.07~2.49,P=0.024）,胎儿分娩季节为冬春季（OR=1.49,95%CI:1.13~1.97,P=0.004）均是新生儿VD缺乏的危险因素。结论 扬州地区新生儿VD水平普遍缺乏,孕妇孕中期和孕晚期VD状况以及胎儿分娩季节与新生儿VD缺乏均存在关联。     

孕期补充维生素D对先天性佝偻病的预防作用

将妊娠28周的受试孕妇随机分为4组,分别1次性口服维生素D(VD)10万IU或肌注VD10万IU或20万IU,对照组口服空白胶囊.结果3个补充组产妇血和脐血25-(OH)D水平以及产妇血钙水平显著高于对照组(P<0.05),而产妇血和脐血25-(OH)D小于27.3nmol/L(11ng/ml)的发生率以及孕后期腿抽筋的发生率显著低于对照组,补充组产妇血25-(OH)D水平高于其妊娠28周时的水平.补充组未发现先天性佝偻病,而对照组先天性佝偻病和可疑先天性佝偻病的发生率显著高于补充组。结果提示孕后期补充VD可明显改善孕妇和胎儿的VD和钙的营养状况.预防先天性佝偻病,品服与肌泣10万IU与20万IU效果相同.     

High prevalence of vitamin D insufficiency in black and white pregnant women residing in the northern United States and their neonates

In utero or early-life vitamin D deficiency is associated with skeletal problems, type 1 diabetes, and schizophrenia, but the prevalence of vitamin D deficiency in U.S. pregnant women is unexplored. We sought to assess vitamin D status of pregnant women and their neonates residing in Pittsburgh by race and season. Serum 25-hydroxyvitamin D (25(OH)D) was measured at 4-21 wk gestation and predelivery in 200 white and 200 black pregnant women and in cord blood of their neonates. Over 90% of women used prenatal vitamins. Women and neonates were classified as vitamin D deficient [25(OH)D<37.5 nmol/L], insufficient [25(OH)D 37.5-80 nmol/L], or sufficient [25(OH)D>80 nmol/L]. At delivery, vitamin D deficiency and insufficiency occurred in 29.2% and 54.1% of black women and 45.6% and 46.8% black neonates, respectively. Five percent and 42.1% of white women and 9.7% and 56.4% of white neonates were vitamin D deficient and insufficient, respectively. Results were similar at <22 wk gestation. After adjustment for prepregnancy BMI and periconceptional multivitamin use, black women had a smaller mean increase in maternal 25(OH)D compared with white women from winter to summer (16.0+/-3.3 nmol/L vs. 23.2+/-3.7 nmol/L) and from spring to summer (13.2+/-3.0 nmol/L vs. 27.6+/-4.7 nmol/L) (P<0.01). These results suggest that black and white pregnant women and neonates residing in the northern US are at high risk of vitamin D insufficiency, even when mothers are compliant with prenatal vitamins. Higher-dose supplementation is needed to improve maternal and neonatal vitamin D nutriture.     

Prepregnancy obesity predicts poor vitamin D status in mothers and their neonates

Obesity is a risk factor for vitamin D deficiency, but this relation has not been studied among pregnant women, who must sustain their own vitamin D stores as well as those of their fetuses. Our objective was to assess the effect of prepregnancy BMI on maternal and newborn 25-hydroxyvitamin D [25(OH)D] concentrations. Serum 25(OH)D was measured at 4-21 wk gestation and predelivery in 200 white and 200 black pregnant women and in their neonates' cord blood. We used multivariable logistic regression models to assess the independent association between BMI and the odds of vitamin D deficiency [25(OH)D <50 nmol/L] after adjustment for race/ethnicity, season, gestational age, multivitamin use, physical activity, and maternal age. Compared with lean women (BMI <25), pregravid obese women (BMI >or=30) had lower adjusted mean serum 25(OH)D concentrations at 4-22 wk (56.5 vs. 62.7 nmol/L; P < 0.05) and a higher prevalence vitamin D deficiency (61 vs. 36%; P < 0.01). Vitamin D status of neonates born to obese mothers was poorer than neonates of lean mothers (adjusted mean, 50.1 vs. 56.3 nmol/L; P < 0.05). There was a dose-response trend between prepregnancy BMI and vitamin D deficiency. An increase in BMI from 22 to 34 was associated with 2-fold (95% CI: 1.2, 3.6) and 2.1-fold (1.2, 3.8) increases in the odds of mid-pregnancy and neonatal vitamin D deficiency, respectively. The rise in maternal obesity highlights that maternal and newborn vitamin D deficiency will continue to be a serious public health problem until steps are taken to identify and treat low 25(OH)D.