Maternal iodine insufficiency and adverse pregnancy outcomes

This study aimed to assess the iodine status of pregnant women in each trimester and to compare the pregnancy outcomes between groups with iodine insufficiency and iodine sufficiency. Longitudinal study on urinary iodine concentration (UIC) in each trimester as well as comparison between women with iodine insufficiency (<150 mcg L^?1) and iodine sufficiency was conducted. Pregnant women without thyroid diseases who had not received iodine supplementation were recruited for UIC measurements in each trimester and were followed up for pregnancy outcomes. In the analysis of 384, 325 and 221 samples in the first, second and third trimester, the medians of UICs were 147.39, 157.01 and 153.07 mcg L^?1, respectively. Of 399 women, 174 (43.6%) had a UIC less than 150 mcg L^?1 (suggesting iodine insufficiency) and 225 (56.4%) had a UIC greater than or equal to 150 mcg L^?1 (suggesting iodine sufficiency). Of 390 women with availability of the final outcomes, 171 and 219 in the insufficiency and sufficiency group, respectively, the rates of preterm birth and low birthweight were significantly higher in the insufficiency group, 17.5% vs. 10.0% (P = 0.031) and 19.9% vs. 12.3% (P = 0.042), respectively. Logistic regression analysis showed that iodine status was an independent risk of preterm birth and low birthweight. Finally, women with a UIC <100 mcg L^?1 had a significantly higher rate of fetal growth restriction, 13/68 vs. 30/322 (P = 0.031). In northern Thailand, a great number of pregnant women had a median UIC less than 150 mcg L^?1 and they had a higher risk of preterm birth and low birthweight. Finally, those with a median UIC of less than 100 mcg L^?1 had a higher risk of fetal growth restriction.     

Maternal phenylketonuria syndrome: congenital heart defects, microcephaly, and developmental outcomes

OBJECTIVE: A cohort of women with phenylketonuria (PKU) were selected to explore the impact of phenylalanine (Phe) levels and other factors on congenital heart defects (CHDs), microcephaly, and development of their offspring. STUDY DESIGN: Three hundred fifty-four women with PKU were followed up weekly with diet records, blood Phe levels, and sonograms obtained at 18 to 20 and 32 weeks' gestation. At birth, 413 offspring were examined and followed up at 6 months and annually by means of Bayley Mental Developmental Index and Psychomotor Developmental Index tests at 1 and 2 years. The women had Wechsler Adult Intelligence Scales and DNA testing. RESULTS: Thirty-one offspring had CHDs; of these, 17 also had microcephaly. Mean Phe levels at 4 to 8 weeks' gestation predicted CHDs (P <.0001). An infant with a CHD had a 3-fold risk of having microcephaly when the mother had higher Phe levels (P =.02). The Bayley Mental Developmental Index and Psychomotor Developmental Index scores correlated with both CHDs (P =.037 and.0015, respectively) and microcephaly (P =.0001 for both). No direct relationship to the PKU mutation was found. CONCLUSION: None of the women whose offspring had CHDs had blood Phe levels in control during the first 8 weeks of gestation. Women with PKU need to be well controlled on a low-phenylalanine diet before conception and throughout pregnancy.     

Maternal folate,one‐carbon metabolism and pregnancy outcomes

Single nucleotide polymorphisms and pre‐ and peri‐conception folic acid (FA) supplementation and dietary data were used to identify one‐carbon metabolic factors associated with pregnancy outcomes in 3196 nulliparous women. In 325 participants, we also measured circulating folate, vitamin B12 and homocysteine. Pregnancy outcomes included preeclampsia (PE), gestational hypertension (GHT), small for gestational age (SGA), spontaneous preterm birth (sPTB) and gestational diabetes mellitus (GDM). Study findings show that maternal genotype MTHFR A1298C(CC) was associated with increased risk for PE, whereas TCN2 C766G(GG) had a reduced risk for sPTB. Paternal MTHFR A1298C(CC) and MTHFD1 G1958A(AA) genotypes were associated with reduced risk for sPTB, whereas MTHFR C677T(CT) genotype had an increased risk for GHT. FA supplementation was associated with higher serum folate and vitamin B12 concentrations, reduced uterine artery resistance index and increased birth weight. Women who supplemented with <800 μg daily FA at 15‐week gestation had a higher incidence of PE (10.3%) compared with women who did not supplement (6.1%) or who supplemented with ≥800 μg (5.4%) (P < .0001). Higher serum folate levels were found in women who later developed GDM compared with women with uncomplicated pregnancies (Mean ± SD: 37.6 ± 8 nmol L⁻¹ vs. 31.9 ± 11.2, P = .007). Fast food consumption was associated with increased risk for developing GDM, whereas low consumption of green leafy vegetables and fruit were independent risk factors for SGA and GDM and sPTB and SGA, respectively. In conclusion, maternal and paternal genotypes, together with maternal circulating folate and homocysteine concentrations, and pre‐ and early‐pregnancy dietary factors, are independent risk factors for pregnancy complications.     

Maternal dietary intake in pregnancy and lactation and allergic disease outcomes in offspring

As the prevalence of allergic disease dramatically rises worldwide, prevention strategies are increasingly being considered. Given the potential modulatory effect of nutritional factors on disease, altering maternal diet during pregnancy and/or lactation has been considered in preventing allergic disease in offspring. Although there are a number of observational studies that have examined possible associations between maternal diet and allergic outcomes in offspring, interventional trials are limited. Furthermore, there is a paucity of studies that have prospectively studied maternal dietary intake as well as measuring maternal and infant biologic samples (blood, urine, breast milk) and their relation to allergic outcomes in infants. There is also a particular need to define terminology such as ‘fruit and vegetables intake’, ‘healthy diet’, and ‘diet diversity’ in order to make studies comparable. In this review, we discuss current evidence of maternal dietary factors during pregnancy and/or lactation that may play a role in the offspring developing allergic disease, including factors such as overall dietary intake patterns, specific whole food consumption (fish, fruit and vegetables, and common allergic foods), and individual immunomodulatory nutrient intakes. Additionally, we discuss the limitations of previous studies and propose improvements to study design for future investigation.     

Maternal smoking during pregnancy and offspring obesity: Meta-analysis

Background:  Recent reports have suggested that maternal smoking may increase the risk of development of obesity in the unborn child in later life, but relatively few cohort studies have been done on the relationship between maternal smoking during pregnancy and future development of metabolic syndrome.
Methods:  A systematic review and meta-analysis of observational studies reporting effect estimates and 95% confidence intervals (95%CI) was conducted on the association between maternal smoking during pregnancy and obesity of future offspring.
Results:  Seventeen papers were identified from 444 English-language papers (key word search: maternal smoking and obesity) in PubMed. All papers showed a positive association between maternal smoking during pregnancy and childhood obesity. The meta-analysis, using the DerSimonian–Laird method, found the association to be statistically significant. In association with maternal smoking during pregnancy and body mass index with more than 95%CI in the offspring aged 3–33 years, the pooled odds ratio calculated from 16 of these 17 studies was 1.64 (95%CI: 1.42–1.90). After adjustment for publication bias, the pooled adjusted odds ratio was 1.52 (95%CI: 1.36–1.70). In addition, confounders of maternal obesity, low social status, low birthweight and not being breast-fed seemed to be risk factors for offspring obesity.
Conclusion:  Maternal smoking during pregnancy may cause future obesity and metabolic syndrome.     

Maternal diet in pregnancy and offspring blood pressure

Associations between maternal nutrient intakes in late pregnancy and offspring blood pressure at 7(1/2) years were investigated in 6944 singletons from the Avon Longitudinal Study of Parents and Children. The only finding was a weak inverse association with omega-3 fatty acids that was lost after adjustment for potential confounders, suggesting that diet in pregnancy does not influence offspring blood pressure in well-nourished populations.     

Maternal diet during pregnancy and islet autoimmunity in offspring

Background:  Recent studies on the etiology of type 1 diabetes mellitus (T1DM) suggest that the components of the infant diet are associated with islet autoimmunity (IA), a precursor of T1DM. The role of prenatal nutritional exposures has not been thoroughly investigated.
Methods:  The Diabetes Autoimmunity Study in the Young has enrolled newborns from 1993 to 2004 at increased risk for T1DM based on human leukocyte antigen (HLA) genotype and family history of T1DM. The child is tested for islet autoantibodies at 9 and 15 months, 2 yr, and annually thereafter. We conducted a cohort study of 642 subjects for whom a Willett food frequency questionnaire for the mother's third trimester diet was completed. A case is defined as a subject who tests positive for islet autoantibodies at two consecutive blood draws and is still positive (or diabetic) at last follow-up (n = 27).
Maternal consumption frequencies of potatoes, other root vegetables, gluten-containing foods, non-gluten cereal grains, cow's milk and cow's milk products, fruits, vegetables, meat and poultry, and fish were analyzed in a survival analysis.
Results:  Adjusting for breast-feeding duration, age at first cereal introduction, ethnicity, HLA genotype, family history of T1DM, and total caloric intake, higher maternal intake of potatoes (hazard ratio for one standard deviation difference: 0.49, 95% confidence interval: 0.28–0.86) was associated with a delayed time to IA onset. No other food groups ingested during pregnancy were associated with IA in the child.
Conclusions:  The composition of the maternal diet during pregnancy may play a role in the offspring's risk of development of IA and potentially T1DM.     

妊娠期合并系统性红斑狼疮对子代影响及作用机制

系统性红斑狼疮(SLE)是一种严重的多系统自身免疫性疾病,绝大多数患者为育龄期女性。妊娠期合并SLE对胎儿、新生儿以及子代远期都会产生影响,包括死胎、流产、胎盘早剥、宫内发育迟缓及早产发生率升高等。少数还可引起新生儿狼疮(NL),甚至对后代神经认知等方面产生影响。另外,SLE患者孕前及孕期需要口服药物控制疾病,其中多数会对子代产生影响。因此,建议SLE患者孕前和孕期严密监测,优化治疗,对其后代进行整体评估,以降低对子代的不利影响。文章利用文献调查分析妊娠期合并SLE对子代影响及其作用机制,同时阐述妊娠期使用SLE药物对后代影响。     

Maternal diet in pregnancy and offspring blood pressure.

Associations between maternal nutrient intakes in late pregnancy and offspring blood pressure at 7(1/2) years were investigated in 6944 singletons from the Avon Longitudinal Study of Parents and Children. The only finding was a weak inverse association with omega-3 fatty acids that was lost after adjustment for potential confounders, suggesting that diet in pregnancy does not influence offspring blood pressure in well-nourished populations.     

Maternal life events during pregnancy and offspring language ability in middle childhood: The Western Australian Pregnancy Cohort Study

Background

There is accumulating evidence for a link between maternal stress during pregnancy and later behavioural and emotional problems in children. Little research has examined other developmental outcomes.

Aim

To determine the effect of maternal stress during pregnancy on offspring language ability in middle childhood.

Study design

Longitudinal pregnancy cohort-study.

Subjects

A total of 2900 mothers were recruited prior to the 18th week of pregnancy, delivering 2868 live births. The language ability of just under half of the offspring cohort (n = 1309; 45.6% of original sample) was assessed in middle childhood (Mean age = 10;7, Standard deviation = 0;2, range: 9;5-11;11).

Outcome measures

Language ability was measured using the Peabody Picture Vocabulary Test-Revised (PPVT-R). The main predictor variable was the frequency of 10 typically ‘stressful’ life events experienced by mothers during early and/or late pregnancy. Children were allocated to four groups according to whether they were exposed to high maternal stress (≥ 2 life events) during early pregnancy only, late pregnancy only, both, or neither.

Results

Mixed-effects regression analyses revealed no association between the maternal experience of two or more stressful life events at any time-point during pregnancy and PPVT-R scores. Repeating the regression analyses with more lenient (≥ 1 life events) or strict (≥ 3 life events) thresholds for defining high-levels of maternal stress did not alter the pattern of findings.

Conclusions

Maternal experience of typically stressful life events during pregnancy has a negligible effect on vocabulary development to middle childhood.     

Maternal primary hyperparathyroidism: discordant outcomes in a twin pregnancy

The case reports a neonate (twin 2 of a twin girl pregnancy) presenting with seizures due to hypocalcaemia. The presumptive cause of the hypocalcaemia was maternal hyperparathyroidism with concurrent vitamin D deficiency. The first twin remained free of hypocalcaemia and was vitamin D replete, despite similar exposure in the pregnancy and similar postnatal care.     

孕期和哺乳期轻度缺锌对仔鼠学习记忆能力的影响

目的探讨孕期和哺乳期母鼠缺锌对仔鼠幼年期学习记忆能力的影响。方法怀孕1 d的孕鼠随机分为轻度缺锌组和对照组,每组3只。缺锌饲料、正常饲料含锌量分别为5 mg/kg、25 mg/kg。产后每窝随机保留4只。至21 d断乳去母鼠,每组12只仔鼠,继续饲以缺锌和正常饲料,分别于28 d及58 d以Morris水迷宫测试仔鼠的短期及长期学习记忆能力。结果学习获得实验(短期记忆)及记忆保持实验(长期记忆):对照组定位能力较好,游泳轨迹以目标象限为主;而缺锌组定位能力较差,游泳轨迹比较分散;缺锌组仔鼠找到平台的潜伏期、总游程大于对照组(P<0.01);两组游速的差异无统计学意义(P>0.05)。随着训练天数的增加,对照组上述各项记录都随着训练天数增加而变化,其中潜伏期和总游程随着训练天数增加而逐步减少,游泳速度、目标象限游程占总游程的百分比随着训练天数的增加而增加,缺锌组的变化趋势不如对照组明显。结论孕期及哺乳期母鼠轻度缺锌影响仔代生长期幼鼠短期与长期学习记忆能力。     

Maternal smoking during pregnancy and offspring overt and covert conduct problems: a longitudinal study

BACKGROUND: Empirical evidence demonstrates that conduct disorder (CD) symptoms tend to cluster into covert and overt domains. We hypothesized that overt and covert CD symptoms may be distinct constructs with distinct risk factors. An important risk factor for CD is maternal smoking during pregnancy. We further investigated this association, attending to overt and covert CD symptom subtypes. Also, we tested whether gender and socioeconomic status (SES) modified this association. METHOD: Participants were male and female adult offspring (n = 682) of a community sample of pregnant women followed longitudinally from prenatal life to age 22. Prospective assessments of maternal smoking during pregnancy were used to predict self-reported DSM-III CD symptoms. RESULTS: Prenatal exposure to smoking was significantly associated with increased overt CD symptoms for participants of low SES, but not for participants of high SES, whereas covert CD symptoms were not associated with prenatal exposure. Gender did not significantly modify the relationship between maternal smoking and CD symptom subtypes. CONCLUSIONS: These results suggest that the previously documented association between maternal smoking and CD may be specific to overt CD symptoms, providing support for the heuristic value of differentiating overt and covert CD symptoms as distinct syndromes. These findings further support smoking prevention programs for pregnant women.     

Maternal aflatoxin exposure during pregnancy and adverse birth outcomes in Uganda

Aflatoxins are toxic metabolites of Aspergillus moulds and are widespread in the food supply, particularly in low‐ and middle‐income countries. Both in utero and infant exposure to aflatoxin B₁ (AFB₁) have been linked to poor child growth and development. The objective of this prospective cohort study was to investigate the association between maternal aflatoxin exposure during pregnancy and adverse birth outcomes, primarily lower birth weight, in a sample of 220 mother–infant pairs in Mukono district, Uganda. Maternal aflatoxin exposure was assessed by measuring the serum concentration of AFB₁‐lysine (AFB‐Lys) adduct at 17.8 ± 3.5 (mean ± SD)‐week gestation using high‐performance liquid chromatography. Anthropometry and birth outcome characteristics were obtained within 48 hr of delivery. Associations between maternal aflatoxin exposure and birth outcomes were assessed using multivariable linear regression models adjusted for confounding factors. Median maternal AFB‐Lys level was 5.83 pg/mg albumin (range: 0.71–95.60 pg/mg albumin, interquartile range: 3.53–9.62 pg/mg albumin). In adjusted linear regression models, elevations in maternal AFB‐Lys levels were significantly associated with lower weight (adj‐β: 0.07; 95% CI: ?0.13, ?0.003; p = 0.040), lower weight‐for‐age z‐score (adj‐β: ?0.16; 95% CI: ?0.30, ?0.01; p = 0.037), smaller head circumference (adj‐β: ?0.26; 95% CI: ?0.49, ?0.02; p = 0.035), and lower head circumference‐for‐age z‐score (adj‐β: ?0.23; 95% CI: ?0.43, ?0.03; p = 0.023) in infants at birth. Overall, our data suggest an association between maternal aflatoxin exposure during pregnancy and adverse birth outcomes, particularly lower birth weight and smaller head circumference, but further research is warranted.