Associations of Body Mass and Body Fat Distribution with Parity Among African-American and Caucasian Women: The CARDIA Study

Associations of parity with body fat and its distribution are poorly understood; therefore, we examined the relationships between parity and obesity in young adult women. Body mass index (BMI), skin folds, and waist-hip ratio were compared in 1452 African-American and 1268 Caucasian nonpregnant women aged 18 to 30, adjusting for age (where no age-parity interactions were present), education, physical activity (assessed by questionnaire) and fitness (assessed by graded exercise test), dietary fat intake, alcohol and smoking. Adjusted mean BMI was significantly higher in African-American women aged 25–30 years with three or more children (28.5 kg/m²) than in those with two (27.0 kg/m²), one (26.2 kg/m²), or no children (26.3 kg/m²). Similar trends were found in Caucasians (BMI = 23.3, 23.4, 23.7, 25.0 kg/m² for parity = 0,1, 2, ≥ 3, respectively), but the mean BMI was significantly higher in African Americans in each parity group. The association between BMI and parity was not present among women 18–24 years of age. Skinfolds were directly associated with parity in African Americans only. Waist-hip ratios were generally lower among nulliparous than parous women in both ethnic groups; race differences were present only among nulliparas. In conclusion, parity was associated with BMI in women aged 25 to 30 years but did not explain ethnicity-related differences in body mass.     

Maternal Cadmium Levels During Pregnancy and the Relationship with Preeclampsia and Fetal Biometric Parameters

Preeclampsia, which is caused by multiple factors, still remains one of the most serious complications of pregnancy. This study was designed to determine cadmium levels in women with preeclampsia compared to those of normotensive women. In this case-control study, maternal blood, umbilical cord blood, and placental cadmium levels were measured by an inductively coupled plasma mass spectrometry system in 51 women presenting consecutively with preeclampsia and 51 normotensive pregnant women. Groups were matched for maternal age, parity, and gestational age. Birth outcomes were recorded, such as gestational age at delivery, birth weight, and Apgar score. Median (interquartile range [IQR]) blood cadmium concentration was 1.21 μg/L (0.76–1.84 μg/L) and 1.09 μg/L (0.72–1.31 μg/L) in women with preeclampsia and normotensive, respectively; values for placental cadmium levels of women with preeclampsia and normotensive were 3.61 μg/kg (2.19–4.37 μg/kg) and 4.28 μg/kg (3.06–5.71 μg/kg), respectively. We observed a statistically significant increase in blood and placental cadmium levels in women with preeclampsia compared to healthy pregnant women. After adjusting for pre-pregnancy body mass index, maternal age, parity, gestational age at sample collection, and maternal calcium and magnesium levels, the odds ratio of having preeclampsia in the high tertile was markedly increased (odds ratio, 7.83 [95% CI, 1.64–37.26]) compared with the low tertile. Interestingly, there was no difference in the cadmium level in umbilical cord blood between the groups. Within the preeclamptic group, higher cadmium status was significantly associated with decreased birth weight. Our study suggested that elevated cadmium level in the maternal circulation could potentially increase the risk of preeclampsia. The results also demonstrate that higher cadmium status may contribute to fetal growth restriction in preeclamptic patients.     

Birth weight from pregnancies dated by ultrasonography in a multicultural British population.

OBJECTIVE--To produce standard curves of birth weight according to gestational age validated by ultrasonography in the British population, with particular reference to the effects of ethnic origin. DESIGN--Retrospective analysis of computerised obstetric database. SETTING--Three large maternity units associated with Nottingham University with over 16,000 deliveries a year. PATIENTS--41,718 women with ultrasound dated singleton pregnancies and delivery between 168 and 300 days'' gestation. MAIN OUTCOME MEASURES--Length of gestation, ethnic origin, parity, maternal height and weight at booking, smoking during pregnancy; the effect of these variables on birth weight. RESULTS--Birth weights from ultrasound dated pregnancies have a higher population mean and show less flattening of the birthweight curve at term than those of pregnancies dated from menstrual history. Significant differences were observed in mean birth weights of babies of mothers of European origin (3357 g), of Afro-Caribbean origin (3173 g), and from the Indian subcontinent (3096 g). There were also significant interethnic differences in length of gestation, parity, maternal height, booking weight, and smoking habit which affected birth weight. The ethnic differences in birth weight were even greater when the effect of smoking was excluded. CONCLUSIONS--Birthweight standards require precise dating of pregnancy and should describe the population from which they were derived. In a heterogeneous maternity population the accurate assessment of an individual baby''s weight needs to take the factors which affect birthweight standards into consideration.     

Association between Gestational Weight Gain and Postpartum Diabetes: Evidence from a Community Based Large Cohort Study

We have investigated the prospective association between excess gestational weight gain (GWG) and development of diabetes by 21 years post-partum using a community-based large prospective cohort study in Brisbane, Australia. There were 3386 mothers for whom complete data were available on GWG, pre-pregnancy BMI and self-reported diabetes 21 years post-partum. We used The Institute of Medicine (IOM) definition to categorize GWG as inadequate, adequate and excessive. We found 839 (25.78%) mothers gained inadequate weight, 1,353 (39.96%) had adequate weight gain and 1,194 (35.26%) had gained excessive weight during pregnancy. At 21 years post-partum, 8.40% of mothers self-reported a diagnosis of diabetes made by their doctor. In the age adjusted model, we found mothers who gained excess weight during pregnancy were 1.47(1.11,1.94) times more likely to experience diabetes at 21 years post-partum compared to the mothers who gained adequate weight. This association was not explained by the potential confounders including maternal age, parity, education, race, smoking, TV watching and exercise. However, this association was mediated by the current BMI. There was no association for the women who had normal BMI before pregnancy and gained excess weight during pregnancy. The findings of this study suggest that women who gain excess weight during pregnancy are at greater risk of being diagnosed with diabetes in later life. This relationship is likely mediated through the pathway of post-partum weight-retention and obesity. This study adds evidence to the argument that excessive GWG during pregnancy for overweight mothers has long term maternal health implications.     

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。     

Plasma trace element (Se,Zn, Cu) concentrations in maternal and umbilical cord blood in Poland

Selenium (Se), copper (Cu), and zinc (Zn) concentrations were determined in plasma of 64 mothers at delivery, 58 nonpregnant women, 64 neonates, and 12 infants, aged 2–12 mo. Se and Zn concentrations in mothers at delivery were significantly lower, and Cu higher than in nonpregnant women. Mean Se and Cu concentrations in newborns were statistically lower than those in mothers at delivery, and Zn and Cu concentrations in preterm infants (n=13) were significantly higher than in fullterm infants (n=51). Maternal parity had no significant influence on the distribution of plasma trace element levels. No significant differences were observed in Se and Zn levels in maternal and cord blood plasma according to birth weight, contrary to maternal Cu concentration. Significant correlations were found between maternal and cord blood Se content, and between maternal plasma Cu concentration and birth weight of neonates.     

Effect of parental anthropometric parameters on neonatal birth weight and birth length

Data on 550 healthy pregnant women, 550 healthy fathers and their healthy term neonates born from singleton pregnancies (37(+0) through 41(+6) week) during a one-year period were reviewed. Maternal mean age was 27.7 +/- 9.37 years, mean pregestational weight 64.0 +/- 9.50 kg, mean gestational weight gain 15.4 +/- 4.33 kg, mean height 169.7 +/- 5.81 cm, and mean gestational age 40.1 +/- 0.95 weeks. Paternal mean age was 31.4 +/- 6.22 years, mean weight 84.6 +/- 10.35 kg, and mean height 182.8 +/- 6.84 cm. Mean birth weight was 3,709.8 +/- 500.48 g and 3,562.5 +/- 443.02 g, and mean birth length 51.5 +/- 1.91 cm and 50.7 +/- 1.62 cm in male and female newborns, respectively, yielding a birth weight greater by 147.3 g and birth length by 0.8 cm in the former. Study variables showed statistically significant correlations: maternal age contributed to the significant correlation between maternal weight and parity, maternal pregestational weight, weight at delivery, gestational weight gain and body height correlated significantly with neonatal birth weight and birth length, gestational age correlated significantly with neonatal weight and length (p = 0.01 all), parity had no major impact (p > 0.05). Paternal height and weight correlated significantly with neonatal birth weight and birth length (p = 0.01). Study results pointed to a significant correlation of maternal pregestational weight, gestational weight gain and body height, and of paternal weight and height with the neonate birth weight and birth length.     

Women With Hypertensive Pregnancies Have Difficulties in Regaining Pre‐pregnancy Weight and Show Metabolic Disturbances

The aim was to determine maternal weight gain and body composition during pregnancy and 3 months postpartum in women with uncomplicated singleton and twin pregnancies and in women with gestational diabetes (GDM) and gestational hypertension (GH). This prospective study includes four groups of subjects: those with an uncomplicated pregnancy (n = 32), those with a diagnosis of GH (n = 28), those with a diagnosis of GDM (n = 52), and those with twin pregnancy (n = 11). Their body compositions were estimated by a bioimpedance analysis and fasting lipids and glucose levels were determined during the pregnancy and 3 months after pregnancy. Women with GDM were 11.7 kg heavier than the reference group before pregnancy, whereas weight before pregnancy was not different in other investigated groups. Weight loss after delivery was attenuated in GH group. Percentage body fat remained elevated in women with GDM (34.1 ± 7.0%) and hypertension (31.5 ± 6.4%) at 3 months after pregnancy. Also their total cholesterol and low‐density lipoprotein (LDL)‐cholesterol levels as well as fasting glucose remained elevated in comparison to values of the reference group. In conclusion, women with hypertensive pregnancies, though not overweight before pregnancy, gain and retain excess gestational weight and this leads to metabolic abnormalities similar to those seen in women GDM. Thus, postpartum period appears to be critical for weight management and interventional programs are called for.     

Circadian Blood Pressure Variability in Normotensive Pregnant Women as a Function of Parity,Maternal Age,and Stage of Gestation

Studies based on conventional office blood pressure (BP) measurements concluded that both maternal age and parity have significant effects on BP during pregnancy. Previous results have also indicated predictable trends of BP variability with gestational age. Accordingly, we have evaluated possible differences in the circadian pattern of ambulatory BP as a function of parity, maternal age, and stage of gestation in normotensive women who were systematically studied by ambulatory BP monitoring during their pregnancies. We analyzed 1408 BP profiles obtained from 126 nulliparous and 109 multiparous pregnant women sampled for 48 consecutive h every 4 weeks from the first obstetric visit (usually within the first trimester of pregnancy) until delivery. Data were divided for comparative analysis according to parity (nulliparous versus multiparous), age (≤25, 26–30, 31–35, and ≥36 yrs), and trimester of gestation. Circadian BP parameters established by population multiple‐components analysis were compared between groups using a nonparametric test. A highly statistically significant circadian pattern described by a model that includes components with periods of 24 and 12 h is demonstrated for systolic and diastolic BP for all groups of pregnant women in all trimesters (always p<0.001). There was no significant difference in the 24 h mean among groups divided by parity at any age or stage of pregnancy. A trend of increasing BP with age was found for diastolic but not for systolic BP. Although statistically significant, differences in the 24 h mean of diastolic BP among groups divided by age were always less than 2 mm Hg. Data obtained from systematic ambulatory monitoring in normotensive pregnant women indicate the lack of differences in BP according to parity. The small, although significant, increase in diastolic BP with age may have scarce influence in the proper identification of women with gestational hypertension. Reference thresholds for BP to be used in the early identification of hypertensive complications in pregnancy could thus be developed as a function of the rest‐activity cycle and gestational age only, and independently of parity or maternal age.     

A Prospective Study of Selenium Concentration and Risk of Preeclampsia in Pregnant Iranian Women: a Nested Case–Control Study

Preeclampsia remains a leading cause of maternal and perinatal mortality and morbidity worldwide; however, its specific etiology still remains obscure. Some studies implicate poor maternal selenium status predisposing the mother to preeclampsia. This study was designed to determine changes in plasma selenium levels in women having preeclampsia as compared with those with normal pregnancy. In a nested case–control study, 650 normal primigravida in their first 24–28 weeks participated in the study. After 3 months of follow-up of all subjects, blood selenium levels were measured in 38 women presenting consecutively with preeclampsia and in 38 women having a normal pregnancy by atomic absorption spectrophotometry. Birth outcomes were recorded, such as gestational age at delivery, height, weight, birth head circumflex and 1-min Apgar score. Preeclampsia affects about 5.84 % of pregnancies, and in our study, there were no significant differences in age, anthropometric indices, and family history of preeclampsia between the preeclamptic and control groups. The selenium concentrations in plasma in women with preeclampsia were significantly lower as compared with those in women with normal pregnancy (70.63?±?21.41 versus 82.03?±?15.54 μg/L, p?<?0.05). Being in the bottom tertile of selenium concentration (less than 62.2 μg/L) was associated with greater risk of preeclampsia in pregnant women. The reduced selenium in the maternal circulations observed in the preeclamptic mothers support the hypothesis that insufficient selenium concentration may be a contributing factor to the pathophysiological mechanisms associated with preeclampsia, and optimizing the dietary selenium intake through supplementation could produce demonstrable clinical benefits.     

Etiology of individual differences in birth weight of twins as a function of maternal smoking during pregnancy.

Birth weight is in large extent influenced by gestational age. In addition genetic and environmental factors determine intrauterine growth and birth weight. The contributions of these factors may be influenced by maternal smoking during pregnancy. We examined birth weight and maternal smoking in a sample of 2930 twin pairs from the Netherlands Twin Register using structural equation modelling. Gestational age accounted for 27-44% of the variance in birth weight. A lower variability of birth weight and a lower association of birth weight with gestational age was found in twins whose mothers smoked during pregnancy. The variance not associated with gestational age was independent of maternal smoking during pregnancy. A systematic smaller part of the variability in birth weight was associated with variability in gestational age in second born twins compared to first born twins. The heritability of interindividual differences in birth weight was modest (10% for twins with non-smoking mothers and 11% for twins with smoking mothers). Common environmental influences other than gestational age accounted for a slightly larger part of the variance not associated with gestational age (17-20%).     

Parity and Body Weight in the United States: Differences by Race and Size of Place of Residence

Objective: In women, parity has been studied in relation to body weights. This study examined whether and how relationships between parity and body weight differ by race and size of place of residence, adjusting for sociodemographic factors (age, income, education, working status, and marital status) and health behaviors (alcohol consumption, birth control pills, diet, physical activity, and smoking). Research Methods and Procedures: A U.S. national sample of 3398 white and black women from the Third National Health and Nutrition Examination Survey was used to study the relationships using multiple linear regression analysis. Results: The parity—weight relationships varied by race and size of place of residence. After adjusting for the covariates, significant relationships between parity and body weight were found only in black women in metropolitan areas and white women in non‐metropolitan areas. Compared with women with no children, white women with two children living in non‐metropolitan areas tended to have lower BMIs, whereas black women in metropolitan areas with one or two children showed higher BMIs. Discussion: Overall, the parity—weight relationships in these groups of women were not strong or linear. The parity—weight relationships of black women in non‐metropolitan areas warrant further examination.     

Updating of normal levels of copper,zinc and selenium in serum of pregnant women

Selenium, copper and zinc status is important in pregnant women. The aim of this study was to establish updated normal ranges for these elements in serum of pregnant women from the Spanish region of Aragon, and to study variation in levels with respect to gestational period and maternal age. The study group consisted of 159 pregnant women who did not suffer from serious pathologies. These samples were classified into four gestational-period groups. Zn and Cu determinations were obtained by flame atomic absorption spectroscopy in a Perkin-Elmer 1100B apparatus, and Se was determined by electrothermal atomic absorption spectrometry with Zeeman correction, in a Perkin-Elmer 4110 ZL apparatus. The concentrations of Cu, Zn and Se averaged 73.61±43.67 μg/dL, 65.37±12.87 μg/dL and 99.59±21.74 μg/L, respectively. The Cu/Zn ratio increased from first trimester to the third trimester (2.07–3.49). There was no significant correlation between Zn and Se levels, but a significant correlation was found between Cu and Se levels (p<0.05) and between Cu and Zn levels (p<0.001). Serum Zn and Se levels decreased over gestation, while serum Cu concentrations increased; in all cases the variation occurred mostly in the first 3 or 4 months, with mean levels then remaining fairly stable until the end of pregnancy. Maternal age did not influence levels of any of the three metals.     

Placental weight mediates the effects of prenatal factors on fetal growth: the extent differs by preterm status

Objective:

Elevated pre‐pregnancy BMI, excessive gestational weight gain (GWG), and gestational diabetes mellitus (GDM) are known determinants of fetal growth. The role of placental weight is unclear. We aimed to examine the extent to which placental weight mediates the associations of pre‐pregnancy BMI, GWG, and GDM with birth weight‐for‐gestational age, and whether the relationships differ by preterm status.

Design and Methods:

We examined 1,035 mother‐infant pairs at birth from the Boston Birth Cohort. Data were collected by questionnaire and clinical measures. Placentas were weighed without membranes or umbilical cords. We performed sequential models excluding and including placental weight, stratified by preterm status.

Results:

We found that 21% of mothers were obese, 42% had excessive GWG, and 5% had GDM. Forty‐one percent were preterm. Among term births, after adjustment for sex, gestational age, maternal age, race, parity, education, smoking, and stress during pregnancy, birth weight‐for‐gestational age z‐score was 0.55 (0.30, 0.80) units higher for pre‐pregnancy obesity vs. normal weight. It was 0.34 (0.13, 0.55) higher for excessive vs. adequate GWG, 0.67 (0.24, 1.10) for GDM vs. no DM, with additional adjustment for pre‐pregnancy BMI. Adding placental weight to the models attenuated the estimates for pre‐pregnancy obesity by 20%, excessive GWG by 32%, and GDM by 21%. Among preterm infants, GDM was associated with 0.67 (0.34, 1.00) higher birth weight‐for‐gestational age z‐score, but pre‐pregnancy obesity and excessive GWG were not. Attenuation by placental weight was 36% for GDM.

Conclusions:

These results suggest that placental weight partially mediates the effects of pre‐pregnancy obesity, GDM, and excessive GWG on fetal growth among term infants.     

Weight loss and race modulate nitric oxide metabolism in overweight women

Weight reduction is associated with a decrease in the risk of developing cardiovascular disease. We hypothesized that, given the central role of reactive oxygen and nitrogen species in vascular biology, changes in nitric oxide (NO) metabolism contribute to benefits of weight loss. In a controlled weight loss trial involving overweight (body mass index (BMI) = 27-30 kg/m(2)), otherwise healthy premenopausal Caucasian and African-American women, serum levels of nitrite and nitrate, as an index of NO production, and protein 3-nitrotyrosine and myeloperoxidase (MPO), as markers of inflammation, were determined. Testing was performed before and after reduction to normal body weight (BMI < 25) under standardized conditions, with controlled diet, and following 1 month of weight maintenance. After weight loss there was an increase in nitrite and nitrate, and levels were higher among African-American women relative to Caucasian counterparts. Whereas weight loss was associated with a decrease in 3-nitrotyrosine in Caucasian women, no change was observed among African-Americans. Furthermore, MPO levels increased in response to weight loss for African-Americans, but did not change in Caucasian women. These data indicate that vascular production of reactive nitrogen species can be modulated by race and weight loss and highlight important racial differences in these responses and are discussed in the context of risk for developing vascular disease.     

Maternal Postpartum Distress and Childhood Overweight

Objective

We investigated associations between maternal postpartum distress covering anxiety, depression and stress and childhood overweight.

Methods

We performed a prospective cohort study, including 21 121 mother-child-dyads from the Danish National Birth Cohort (DNBC). Maternal distress was measured 6 months postpartum by 9 items covering anxiety, depression and stress. Outcome was childhood overweight at 7-years-of age. Multiple logistic regression analyses were performed and information on maternal age, socioeconomic status, pre-pregnancy BMI, gestational weight gain, parity, smoking during pregnancy, paternal BMI, birth weight, gestational age at birth, sex, breastfeeding and finally infant weight at 5 and 12 month were included in the analyses.

Results

We found, that postpartum distress was not associated with childhood risk of overweight, OR 1.00, 95%CI [0.98–1.02]. Neither was anxiety, depression, or stress exposure, separately. There were no significant differences between the genders. Adjustment for potential confounders did not alter the results.

Conclusion

Maternal postpartum distress is apparently not an independent risk factor for childhood overweight at 7-years-of-age. However, we can confirm previous findings of perinatal determinants as high maternal pre-pregnancy BMI, and smoking during pregnancy being risk factors for childhood overweight.     

Risk factors and outcomes of maternal obesity and excessive weight gain during pregnancy

Objective:

The prevalence of overweight and obesity among women of reproductive age is increasing. We aimed to determine risk factors and maternal, fetal and childhood consequences of maternal obesity and excessive gestational weight gain.

Design and Methods:

The study was embedded in a population‐based prospective cohort study among 6959 mothers and their children. The study was based in Rotterdam, The Netherlands (2001–2005).

Results:

Maternal lower educational level, lower household income, multiparity, and FTO risk allel were associated with an increased risk of maternal obesity, whereas maternal European ethnicity, nulliparity, higher total energy intake, and smoking during pregnancy were associated with an increased risk of excessive gestational weight gain (all p‐values <0.05). As compared to normal weight, maternal obesity was associated with increased risks of gestational hypertension (OR 6.31 (95% CI 4.30, 9.26)), preeclampsia (OR (3.61, (95% CI 2.04, 6.39)), gestational diabetes (OR 6.28 (95%CI 3.01, 13.06)), caesarean delivery (OR 1.91 (95% CI 1.46, 2.50)), delivering large size for gestational age infants (OR 2.97 (95% CI 2.16, 4.08)), and childhood obesity (OR 5.02 (95% CI:2.97, 8.45)). Weaker associations of excessive gestational weight gain with maternal, fetal and childhood outcomes were observed, with the strongest effects for first trimester weight gain.

Conclusions:

Our study shows that maternal obesity and excessive weight gain during pregnancy are associated with socio‐demographic, lifestyle, and genetic factors and with increased risks of adverse maternal, fetal and childhood outcomes. As compared to prepregnancy overweight and obesity, excessive gestational weight gain has a limited influence on adverse pregnancy outcomes.     

Tobacco Smoke Exposure During Pregnancy Increases Maternal Blood Lead Levels Affecting Neonate Birth Weight

To assess the effect of lead exposure from cigarette smoke on fetal growth, blood lead concentrations were measured using inductively coupled plasma mass spectrometry in 150 healthy pregnant women. Mean lead concentrations in plasma and whole blood were significantly higher in the smoking group compared with the nonsmoking group in each trimester of pregnancy (p?<?0.001). Logistic regression analysis showed the highest impact of the number of cigarettes smoked per day for serum lead concentration (β?=?0.238; p?<?0.05), while in whole blood, it was duration of smoking before conception (β?=?0.297; p?<?0.001). Birth weight of the smoking mothers' infants was significantly lower (mean?±?SEM, 3,192?±?50.8 and 3,569?±?49.6 g, respectively; p?<?0.001) and negatively correlated with lead levels in plasma (r?=??0.38; p?<?0.001) and in whole blood (r?=??0.27; p?<?0.001). Therefore, it is suggested that smoking during pregnancy increases lead concentrations in maternal blood. Fetal exposure to low doses of lead in utero may be a serious risk factor causing lower birth weight.     

Association of Second and Third Trimester Weight Gain in Pregnancy with Maternal and Fetal Outcomes

Objective

To investigate the association between weekly weight gain, during the second and third trimesters, classified according to the 2009 Institute of Medicine (IOM/NRC) recommendations, and maternal and fetal outcomes.

Methods

Gestational weight gain was evaluated in 2,244 pregnant women of the Brazilian Study of Gestational Diabetes (Estudo Brasileiro do Diabetes Gestacional – EBDG). Outcomes were cesarean delivery, preterm birth and small or large for gestational age birth (SGA, LGA). Associations between inadequate weight gain and outcomes were estimated using robust Poisson regression adjusting for pre-pregnancy body mass index, trimester-specific weight gain, age, height, skin color, parity, education, smoking, alcohol consumption, gestational diabetes and hypertensive disorders in pregnancy.

Results

In fully adjusted models, in the second trimester, insufficient weight gain was associated with SGA (relative risk [RR] 1.72, 95% confidence interval [CI] 1.26–2.33), and excessive weight gain with LGA (RR 1.64, 95% CI 1.16–2.31); in third trimester, excessive weight gain with preterm birth (RR 1.70, 95% CI 1.08–2.70) and cesarean delivery (RR 1.21, 95% CI 1.03–1.44). Women with less than recommended gestational weight gain in the 2^nd trimester had a lesser risk of cesarean deliveries (RR 0.82, 95% CI 0.71–0.96) than women with adequate gestational weight gain in this trimester.

Conclusion

Though insufficient weight gain in the 3^rd trimester was not associated with adverse outcomes, other deviations from recommended weight gain during second and third trimester were associated with adverse pregnancy outcomes. These findings support, in part, the 2009 IOM/NRC recommendations for nutritional monitoring during pregnancy.