出生缺陷与优生研究进展分析

目的:对导致新生儿出生缺陷的原因及干预措施进行分析,为优生研究提供参考;方法:以我院附属医院2011年6月——2012年6月分娩存在出生缺陷的38例新生儿为研究对象,对其导致出生缺陷的原因进行分析,根据分析结果进行优生干预,并对研究的进展进行总结;结果:导致新生儿出生缺陷主要有遗传因素、环境因素及两者综合作用,通过病因干预、诊断干预和治疗干预可以降低出生缺陷,提高优生率;结论对出生缺陷进行有针对性的干预,能够显著改善新生儿的质量,对优生具有重要的价值。     

出生缺陷监测现状及干预概况

<正>出生缺陷是指新生儿在胚胎时期就出现功能、结构或代谢方面的异常。出生缺陷不仅可导致孕妇孕早期流产,还可发生死胎、死产及新生儿死亡等,存活患儿也是社会和家庭的负担。因此应将优生优育真正落到实处,提高我国人口质量,降低出生缺陷发生率。为提高有效的干预措施,作者结合我国目前出生缺陷监测现状及存在的问题综述如下。1出生缺陷监测背景我国的人口出生缺陷高发,出生缺陷发生率为4%~     

农村地区高危孕产妇医疗依从性调查分析与对策

目的了解农村地区高危孕产妇医疗依从性状况,为妇幼保健管理模式及提高高危孕产妇医疗依从性提供依据。方法对2016年1~10月我院登记在在册的上林县白圩镇辖区内居住的农业户籍高危孕产妇360例,以问卷调查(可电话询问问卷内容)方式进行依从性调查,并进行分析不依从原因,采取提高依从性对策。结果依从患者受教育程度明显高于不依从患者,且前者的妊娠次数明显低于后者(P0.05),但高危评分无显著性差异(P0.05)。高危孕产妇不依从的原因主要有医保的报销额度、医务人员的服务态度、家庭条件、家人的意见、对孕产期风险缺乏认识和时间原因,其中家人的意见和对孕产期风险缺乏认识所占比例较高。结论农村地区孕产妇的年龄、妊娠次数与依从性成反比,受教育程度和依从性成正比。提高学历水平和加强健康教育、改变生育观念对依从性的提高有一定效果,采取有效的对策提高农村地区高危孕产妇的医疗依从性对提高我国出生人口素质具有重要意义。     

围产儿出生缺陷分析及干预措施

摘要目的：掌握围产儿出生缺陷的发生情况,探讨引起围产儿出生缺陷的相关因素,为制订及完善出生缺陷预防对策及干预措施提供科学依据。方法：按照全国出生缺陷监测中心制定的监测方案,对2010年10月1日～2011年9月30日在湘潭市县级及以上医疗保健机构住院分娩的围生儿出生缺陷监测资料进行分析。结果：5年出生缺陷的平均发生率为93．30／万,出生缺陷的发生率无明显趋势（x2=0．114,P=0．736）乡村的出生缺陷发生率明显高于城镇（X2=24．638,P〈O．001）,男性围产儿的出生缺陷发生率显著高于女性（XZ=6．693,P=0．010）,出生缺陷的发生率与季节无关（x2=3．852,P=0．278）,出生缺陷的围产儿死亡率大大高于非出生缺陷）L（X2=2904．583,P〈0．001）,先天性心脏病、肢体畸形（并指／趾、多指／趾、肢体短缩、马蹄内翻足）、唇裂及唇腭裂是高发的出生缺陷。结论：减少出生缺陷的发生是一项长期工程,需要采取综合措施,从各个环节入手,以预防为主,加强优生优育健康教育,落实婚前及围产期保健,推行新生儿疾病筛查,可有效降低出生缺陷的发病率,提高出生人口素质。     

线上孕妇学校在产前健康教育中的效果研究

目的探讨使用线上孕妇学校进行产前健康教育对孕期保健及妊娠结局的影响。方法随机选择门诊早孕建卡的孕妇1000例,分为对照组和研究组各500例。对照组进行传统孕妇学校健康教育干预,研究组进行线上孕妇学校健康教育干预,比较两组孕妇母婴健康素养水平和按时产检率、产前筛查率以及不良妊娠结局发生率。结果研究组孕妇母婴健康素养水平、按时产检率、产前筛查率均高于对照组(P0.05),不良妊娠结局发生率低于对照组(P0.05)。结论线上孕妇学校健康教育效果优于传统孕妇学校健康教育,可提高母婴健康素养水平及按时产检率、产前筛查率,降低不良妊娠结局发生率,保障母婴安全,提高人口出生素质。     

孕妇孕期营养指导及体质量控制对妊娠结局的影响

目的:对孕妇进行孕期营养指导及体质量控制,探究其对妊娠结局的影响。方法:将2011年2月-2014年2月期间我院收治的孕产妇150例纳入本次研究,所有研究对象随机均衡分为研究组和对照组,每组各75例。对照组孕产妇仅行常规妇科检查,研究组孕产妇在医护人员指导下行孕期营养指导和体质量控制,比较两组分娩方式,妊娠过程状况及围产儿情况。结果:研究组剖宫产率为17.33%低于对照组的57.33%,组间差异存在统计学意义(P0.05)。研究组贫血、羊水过少、产后出血率均低于对照组,差异有统计学意义(P0.05)。研究组胎龄及巨大儿及胎儿窘迫率均低于对照组,差异有统计学意义(P0.05)。结论:孕产妇在孕期进行营养膳食指导,控制体质量在合理范围内,可以改善孕妇妊娠结局,降低妊娠过程中并发症发病率,提高围产儿状况,保证孕妇和婴儿健康。     

孕期健康教育在产科门诊护理中的临床应用分析

目的:分析孕期健康教育在产科门诊护理中的临床应用。方法:将2011年3月-2014年5月期间,我院门诊妊娠期妇女128例为研究对象,随机将其分成观察组64例以及对照组64例,其中对照组采用常规检查以及常规健康教育,观察组采用孕期健康教育,对比分析两组孕产妇的自然分娩率、产后出血以及相关知识掌握率。结果:在经过不同的护理模式后,观察组孕产妇自然分娩率为96.9%(62/64)、产后出血1.6%(1/64)、母乳喂养98.4%(63/64);对照组孕产妇自然分娩率为81.3%(52/64)、产后出血7.8%(5/64)、母乳喂养82.8%(53/64),两组间比较差异显著(P0.05)具备统计学意义。结论:在门诊护理中采用孕期健康教育能够提升孕产妇的自然分娩率以及母乳喂养,同时降低了产后出血,因此值得推广使用。     

哪些病原体感染与优生优育有关?

问：哪些病原体感染与优生优育有关？ 答：随着人们对母婴保健关注程度的提高,宫内感染造成的影响越来越多的引起了人们的重视。许多研究均已证实,孕期感染的一些病原体不仅威胁母体健康,还可以可通过垂直传播途径,造成胎儿感染。许多病原体与早产及流产的发生相关......     

湘潭地区不同孕期、不同年龄孕妇微量元素变化分析

目的:了解湘潭地区妊娠期妇女不同孕期、不同年龄微量元素的变化规律及缺乏情况,为孕妇合理地补充血清微量元素提供理论依据,从而达到提高孕期保健,减少不良妊娠事件发生的目的.方法:将255例观察组孕妇按妊娠时间分成早孕组(≤12周),中孕组(＞12～＜28周),晚孕组(≥28周),同时选取45例的健康非妊娠妇女作对照;并且根据年龄将观察组孕妇分为30岁以上组(年龄≥30岁)和30岁以下组(年龄＜30岁),采用原子吸收分光光度法测定不同孕期、不同年龄孕妇血清铁、钙、锌、镁、铜5种元素的含量,并统计出不同孕期、不同年龄孕妇5种元素的缺乏情况.结果:不同孕期、不同年龄孕妇各种微量元素均值比较有显著性差异(P＜0.05),表明微量元素的失衡程度与年龄和孕期有关.各孕期铁锌钙的缺乏率与对照组比较有统计学差异(P＜0.05);30岁以上组中铁、钙、锌与30岁以下组有明显差异(P＜0.05).结论:湘潭地区妊娠期孕妇不同孕期、不同年龄间微量元素含量存在着一定差异,孕妇应根据孕周和年龄的不同合理加强对铁、钙、锌等微量元素的补充,以避免孕期不良妊娠结局的发生,提高优生优育.     

215 例出生缺陷围生儿临床分析

目的:探讨近几年出生缺陷发生率的变化,反思出生缺陷的发生与干预措施之间的关系。方法:收集1999年1月至2010年12月在我院分娩的围生儿7875例,回顾分析十二年我院检查及分娩的胎儿出生缺陷变化情况,分析其出生缺陷的种类及发生率的变化。结果:有出生缺陷的围产儿215例,发生率为27.30‰,行产前诊断确诊后在孕妇知情同意下选择治疗性引产的88例,纠正足月活产婴儿的出生缺陷率为16.13‰,差异有显著意义(x2=22.16,P<0.01)。结论:有效的产前诊断技术能及早作出出生缺陷的宫内诊断,对优生优育、提高人口素质及疾病控制有很大帮助。     

Evaluation of preterm births and birth defects in liveborn infants of US military women who received smallpox vaccine

BACKGROUND: Women serving in the US military have some unique occupational exposures, including exposure to vaccinations that are rarely required in civilian professions. When vaccinations are inadvertently given during pregnancy, such exposures raise special concerns. These analyses address health outcomes, particularly preterm births and birth defects, among infants who appear to have been exposed to maternal smallpox vaccination in pregnancy. METHODS: This retrospective cohort study included 31,420 infants born to active‐duty military women during 2003–2004. We used Department of Defense databases to define maternal vaccination and infant health outcomes. Multivariable regression models were developed to describe associations between maternal smallpox vaccination and preterm births and birth defects in liveborn infants. RESULTS: There were 7,735 infants identified as born to women ever vaccinated against smallpox, and 672 infants born to women vaccinated in the first trimester of pregnancy. In multivariable modeling, maternal smallpox vaccination in pregnancy was not associated with preterm or extreme preterm delivery. Maternal smallpox vaccination in the first trimester of pregnancy was not significantly associated with overall birth defects (OR 1.40; 95% CI: 0.94, 2.07), or any of seven specific defects individually modeled. CONCLUSIONS: Results may be reassuring that smallpox vaccine, when inadvertently administered to pregnant women, is not associated with preterm delivery or birth defects in liveborn infants. Birth Defects Research (Part A) 2008. © 2008 Wiley‐Liss, Inc.     

Maternal Prepregnancy Body Mass Index and Gestational Weight Gain on Pregnancy Outcomes

Objective

The aim of the present study was to evaluate the single and joint associations of maternal prepregnancy body mass index (BMI) and gestational weight gain (GWG) with pregnancy outcomes in Tianjin, China.

Methods

Between June 2009 and May 2011, health care records of 33,973 pregnant women were collected and their children were measured for birth weight and birth length. The independent and joint associations of prepregnancy BMI and GWG based on the Institute of Medicine (IOM) guidelines with the risks of pregnancy and neonatal outcomes were examined by using Logistic Regression.

Results

After adjustment for all confounding factors, maternal prepregnancy BMI was positively associated with risks of gestational diabetes mellitus (GDM), pregnancy-induced hypertension, caesarean delivery, preterm delivery, large-for-gestational age infant (LGA), and macrosomia, and inversely associated with risks of small-for-gestational age infant (SGA) and low birth weight. Maternal excessive GWG was associated with increased risks of pregnancy-induced hypertension, caesarean delivery, LGA, and macrosomia, and decreased risks of preterm delivery, SGA, and low birth weight. Maternal inadequate GWG was associated with increased risks of preterm delivery and SGA, and decreased risks of LGA and macrosomia, compared with maternal adequate GWG. Women with both prepregnancy obesity and excessive GWG had 2.2–5.9 folds higher risks of GDM, pregnancy-induced hypertension, caesarean delivery, LGA, and macrosomia compared with women with normal prepregnancy BMI and adequate GWG.

Conclusions

Maternal prepregnancy obesity and excessive GWG were associated with greater risks of pregnancy-induced hypertension, caesarean delivery, and greater infant size at birth. Health care providers should inform women to start the pregnancy with a BMI in the normal weight category and limit their GWG to the range specified for their prepregnancy BMI.     

Multidimensional analysis of the essential elements in pregnant women's whole blood and characterization of maternal status by elemental pattern

BackgroundDuring pregnancy, the fetus needs to obtain a lot of nutrients from the mother, but the micronutrient deficiencies in pregnancy are not clear at present, and there is no reliable basis for nutrient intake and supplement. The purpose of this study was to understand the levels of essential elements in whole blood of pregnant women during various pregnancy stages at different ages and in different regions, to evaluate the deficiency of essential elements in Chinese pregnant women, and to explore the feasibility of using the elemental pattern to characterize maternal status.MethodsWhole blood samples of 11222 healthy pregnant women enrolled in different areas of China from Jan–Dec 2019, were analyzed for concentrations of six essential elements including Mn, Cu, Zn, Ca, Mg, and Fe, using the inductively coupled plasma mass spectrometer. A retrospective comparative study during different pregnancy periods at different ages and in different regions in whole blood essential elements content from non-pregnant normal women and pregnant normal women was developed using multivariate statistical analysis. Principal component analysis evaluation elemental pattern was used to characterize pregnancy status of pregnant women.ResultsIn general, the levels of six essential elements in whole blood of pregnant women can satisfy the needs of normal physiological activities. With the development of pregnancy, the contents of Cu and Mn increased, while the contents of Fe and Mg decreased, and the contents of Zn and Ca have no noteworthy change. At the same gestation stage, the Cu content in whole blood of elderly pregnant women was higher. There were some differences in whole blood essential elements content of pregnant women in different regions. Principal component analysis and heat map analysis showed the feasibility of using bioinformatics research strategies to identify different pregnancies.ConclusionsThere are differences in the content of whole blood essential elements of women at different stages of pregnancy in different regions. It was found that there was no obvious deficiency in whole blood essential elements levels of pregnant women in recent years. The pattern of essential elements has a certain application potential in the evaluation of pregnancy and pregnant women's health status.     

高龄孕妇分娩新生儿出生体重及出院转归的影响因素分析

摘要 目的：探讨高龄孕妇分娩新生儿出生体重及出院转归的影响因素。方法：选择2021年01月到2022年01月与我院就诊的198例产妇作为研究对象,根据孕妇分娩时的年龄分为观察组和对照组,分娩时年龄满35周岁为高龄产妇组（98例）,分娩时年龄为20~34周岁为适龄组（100例）。比较适龄孕妇和高龄孕妇新生儿出生体重情况和新生儿住院时间,对高龄孕妇新生儿体重和新生儿出院转归影响因素进行Logistic单因素分析和多因素分析。结果：与适龄孕妇相比,高龄孕妇新生儿低出生体重儿、巨大儿发生率更高（P<0.05）,新生儿住院时间明显更长（P<0.05）。对高龄孕妇新生儿体重进行单因素分析结果显示,妊娠糖尿病、产检检查、分娩方式、是否使用催产素、分娩时麻醉方式和脐带情况与高龄孕妇新生儿体重无关（P>0.05）,孕妇年龄、孕前BMI、孕期体重增加情况、妊娠高血压、合并其他疾病状况、孕次、产次、羊水情况与高龄孕妇新生儿体重相关（P<0.05）。进行Logistic多因素回归分析结果显示,孕妇年龄、孕前BMI、孕期体重增加情况、孕次、产次、羊水情况是影响高龄孕妇新生儿出生体重的独立危险因素（P<0.05）。对新生儿出院转归情况进行单因素分析结果显示,胎次、开奶时间、喂养方式和有无接受治疗与新生儿出院转归无相关性（P>0.05）,胎龄、出生体重、Apgar评分、出生窒息史、有无伴发疾病与新生儿转归相关（P<0.05）。进行Logistic多因素分析结果显示,胎龄、出生体重、Apgar评分、出生窒息史、有无伴发病是影响新生儿出院转归的独立危险因素（P<0.05）。结论：孕妇年龄、孕前BMI、孕期体重增加情况、孕次、产次、羊水情况是影响高龄孕妇新生儿出生体重的独立危险因素。新生儿出院转归受到胎龄、出生体重、Apgar评分、出生窒息史、有无伴发病影响。     

The Association of Ethnic Minority Density with Late Entry into Antenatal Care in the Netherlands

In the Netherlands, non-Western ethnic minority women make their first antenatal visit later than native Dutch women. Timely entry into antenatal care is important as it provides the opportunity for prenatal screening and the detection of risk factors for adverse pregnancy outcomes. In this study we explored whether women''s timely entry is influenced by their neighborhood. Moreover, we assessed whether ethnic minority density (the proportion of ethnic minorities in a neighborhood) influences Western and non-Western ethnic minority women''s chances of timely entry into care differently. We hypothesized that ethnic minority density has a protective effect against non-Western women''s late entry into care. Data on time of entry into care and other individual-level characteristics were obtained from the Netherlands Perinatal Registry (2000-2008; 97% of all pregnancies). We derived neighborhood-level data from three other national databases. We included 1,137,741 pregnancies of women who started care under supervision of a community midwife in 3422 neighborhoods. Multi-level logistic regression was used to assess the associations of individual and neighborhood-level determinants with entry into antenatal care before and after 14 weeks of gestation. We found that neighborhood characteristics influence timely entry above and beyond individual characteristics. Ethnic minority density was associated with a higher risk of late entry into antenatal care. However, our analysis showed that for non-Western women, living in high ethnic minority density areas is less detrimental to their risk of late entry than for Western women. This means that a higher proportion of ethnic minority residents has a protective effect on non-Western women''s chances of timely entry into care. Our results suggest that strategies to improve timely entry into care could seek to create change at the neighborhood level in order to target individuals likely of entering care too late.     

Maternal and child health in China.

China has made great progress in improving the health of women and children over the past two generations. The success has been attributed to improved living standards, public health measures, and good access to health services. Although overall infant and maternal mortality rates are relatively low there are large differences in patterns of mortality between urban and rural areas. The Chinese have developed a hierarchical network of maternal and child health services, with each level taking a supervisory and teaching role for the level below it. Maternal and child health in China came to international attention in 1995 with the promulgation of the maternal and child health law. In China this was seen as a means of prioritising resources and improving the quality of services, but in the West it was widely described as a law on eugenics.     

Tuberculosis Disease during Pregnancy and Treatment Outcomes in HIV-Infected and Uninfected Women at a Referral Hospital in Cape Town

BackgroundTuberculosis during pregnancy and treatment outcomes are poorly defined in high prevalence tuberculosis and HIV settings.MethodsA prospective cohort study of pregnant and postpartum women identified to be routinely on antituberculosis treatment was conducted at Tygerberg Hospital, Cape Town, South Africa, from January 2011 through December 2011. Maternal tuberculosis disease spectrum and tuberculosis-exposed newborns were characterized by maternal HIV status. Maternal tuberculosis treatment outcomes were documented and a multivariable regression model identified predictors of unfavourable tuberculosis treatment outcomes. Infant outcomes were also described.ResultsSeventy-four women with tuberculosis, 53 (72%) HIV-infected, were consecutively enrolled; 35 (47%) were diagnosed at delivery or postpartum and 22 (30%) of women reported previous antituberculosis treatment. HIV-infected women were 5.67 times more likely to have extrapulmonary tuberculosis (95% CI 1.18–27.25, p = 0.03). All 5 maternal deaths were amongst HIV-infected women. Birth outcomes were available for 75 newborns (2 sets of twins, missing data for 1 stillbirth). Of the 75 newborns, 49 (65%) were premature and 44 (59%) were low birth weight (LBW; <2500 grams). All 6 infants who died and the 4 stillbirths were born to HIV-infected women. Unfavourable tuberculosis treatment outcomes were documented in 33/74 (45%) women. Unfavourable maternal tuberculosis outcome was associated with delivery of LBW infants (OR 3.83; 95% CI 1.40–10.53, p = 0.009).ConclusionsA large number of pregnant women with tuberculosis presented at a provincial referral hospital. All maternal and infant deaths occurred in HIV-infected women and their newborns. Maternal tuberculosis treatment outcomes were poor.     

Impact of Community-Based Maternal Health Workers on Coverage of Essential Maternal Health Interventions among Internally Displaced Communities in Eastern Burma: The MOM Project

Background

Access to essential maternal and reproductive health care is poor throughout Burma, but is particularly lacking among internally displaced communities in the eastern border regions. In such settings, innovative strategies for accessing vulnerable populations and delivering basic public health interventions are urgently needed.

Methods

Four ethnic health organizations from the Shan, Mon, Karen, and Karenni regions collaborated on a pilot project between 2005 and 2008 to examine the feasibility of an innovative three-tiered network of community-based providers for delivery of maternal health interventions in the complex emergency setting of eastern Burma. Two-stage cluster-sampling surveys among ever-married women of reproductive age (15–45 y) conducted before and after program implementation enabled evaluation of changes in coverage of essential antenatal care interventions, attendance at birth by those trained to manage complications, postnatal care, and family planning services.

Results

Among 2,889 and 2,442 women of reproductive age in 2006 and 2008, respectively, population characteristics (age, marital status, ethnic distribution, literacy) were similar. Compared to baseline, women whose most recent pregnancy occurred during the implementation period were substantially more likely to receive antenatal care (71.8% versus 39.3%, prevalence rate ratio [PRR] = 1.83 [95% confidence interval (CI) 1.64–2.04]) and specific interventions such as urine testing (42.4% versus 15.7%, PRR = 2.69 [95% CI 2.69–3.54]), malaria screening (55.9% versus 21.9%, PRR = 2.88 [95% CI 2.15–3.85]), and deworming (58.2% versus 4.1%, PRR = 14.18 [95% CI 10.76–18.71]. Postnatal care visits within 7 d doubled. Use of modern methods to avoid pregnancy increased from 23.9% to 45.0% (PRR = 1.88 [95% CI 1.63–2.17]), and unmet need for contraception was reduced from 61.7% to 40.5%, a relative reduction of 35% (95% CI 28%–40%). Attendance at birth by those trained to deliver elements of emergency obstetric care increased almost 10-fold, from 5.1% to 48.7% (PRR = 9.55 [95% CI 7.21–12.64]).

Conclusions

Coverage of maternal health interventions and higher-level care at birth was substantially higher during the project period. The MOM Project''s focus on task-shifting, capacity building, and empowerment at the community level might serve as a model approach for similarly constrained settings. Please see later in the article for the Editors'' Summary     

Comprehensive Approach to Improving Maternal Health and Achieving MDG 5: Report from the Mountains of Lesotho

Background

Although it is now widely recognized that reductions in maternal mortality and improvements in women''s health cannot be achieved through simple, vertical strategies, few programs have provided successful models for how to integrate services into a comprehensive program for maternal health. We report our experience in rural Lesotho, where Partners In Health (PIH) in partnership with the Ministry of Health and Social Welfare implemented a program that provides comprehensive care of pregnant women from the community to the clinic level.

Methods

Between May and July 2009, PIH trained 100 women, many of whom were former traditional birth attendants, to serve as clinic-affiliated maternal health workers. They received performance-based incentives for accompanying pregnant women during antenatal care (ANC) visits and facility-based delivery. A nurse-midwife provided ANC and delivery care and supervised the maternal health workers. To overcome geographic barriers to delivering at the clinic, women who lived far from the clinic stayed at a maternal lying-in house prior to their expected delivery dates. We analyzed data routinely collected from delivery and ANC registers to compare service utilization before and after implementation of the program.

Results

After the establishment of the program, the average number first ANC visits increased from 20 to 31 per month. The clinic recorded 178 deliveries in the first year of the program and 216 in the second year, compared to 46 in the year preceding the program. During the first two years of the program, 49 women with complications were successfully transported to the district hospital, and no maternal deaths occurred among the women served by the program.

Conclusions

Our results demonstrate that it is possible to achieve dramatic improvements in the utilization of maternal health services and facility-based delivery by strengthening human resource capacity, implementing active follow-up in the community, and de-incentivizing home births.     

Influence of maternal nutrition on outcome of pregnancy: prospective cohort study

ObjectiveTo investigate the relations of maternal diet and smoking during pregnancy to placental and birth weights at term.DesignProspective cohort study.SettingDistrict general hospital in the south of England.Participants693 pregnant nulliparous white women with singleton pregnancies who were selected from antenatal booking clinics with stratified random sampling.ResultsPlacental and birth weights were unrelated to the intake of any macronutrient. Early in pregnancy, vitamin C was the only micronutrient independently associated with birth weight after adjustment for maternal height and smoking. Each ln mg increase in vitamin C was associated with a 50.8 g (95% confidence interval 4.6 g to 97.0 g) increase in birth weight. Vitamin C, vitamin E, and folate were each associated with placental weight after adjustment for maternal characteristics. In simultaneous regression, however, vitamin C was the only nutrient predictive of placental weight: each ln mg increase in vitamin C was associated with a 3.2% (0.4 to 6.1) rise in placental weight. No nutrient late in pregnancy was associated with either placental or birth weight.ConclusionsConcern over the impact of maternal nutrition on the health of the infant has been premature. Maternal nutrition, at least in industrialised populations, seems to have only a small effect on placental and birth weights. Other possible determinants of fetal and placental growth should be investigated.

Key messages

• Placental and infant birth weights were not associated with the intake of any macronutrient early or later in pregnancy
• After adjustment for the effects of maternal height and smoking, only vitamin C independently predicted birth weight. The expected mean difference in birth weight for infants with mothers in the upper and lower thirds of intake was about 70 g
• Vitamin C was the only nutrient that independently predicted placental weight, but again this relation was of doubtful clinical significance
• Among relatively well nourished women in industrialised countries, maternal nutrition seems to have only a marginal impact on infant and placental size. Other causes of variation in the size of clinically normal infants should now be investigated