The Impact of Parental Personality on Birth Outcomes: A Prospective Cohort Study

Gene-environment interactions related to maternal exposure to environmental and lifestyle-related chemicals during pregnancy and the resulting adverse fetal growth: a review

Background

There are only limited numbers of reviews on the association of maternal-child genetic polymorphisms and environmental and lifestyle-related chemical exposure during pregnancy with adverse fetal growth. Thus, this article aims to review: (1) the effect of associations between the above highlighted factors on adverse fetal growth and (2) recent birth cohort studies regarding environmental health risks.

Methods

Based on a search of the PubMed database through August 2021, 68 epidemiological studies on gene-environment interactions, focusing on the association between environmental and lifestyle-related chemical exposure and adverse fetal growth was identified. Moreover, we also reviewed recent worldwide birth cohort studies regarding environmental health risks.

Results

Thirty studies examined gene-smoking associations with adverse fetal growth. Sixteen maternal genes significantly modified the association between maternal smoking and adverse fetal growth. Two genes significantly related with this association were detected in infants. Moreover, the maternal genes that significantly interacted with maternal smoking during pregnancy were cytochrome P450 1A1 (CYP1A1), X-ray repair cross-complementing protein 3 (XRCC3), interleukin 6 (IL6), interleukin 1 beta (IL1B), human leukocyte antigen (HLA) DQ alpha 1 (HLA-DQA1), HLA DQ beta 1 (HLA-DQB1), and nicotinic acetylcholine receptor. Fetal genes that had significant interactions with maternal smoking during pregnancy were glutathione S-transferase theta 1 (GSTT1) and fat mass and obesity-associated protein (FTO). Thirty-eight studies examined the association between chemical exposures and adverse fetal growth. In 62 of the 68 epidemiological studies (91.2%), a significant association was found with adverse fetal growth. Across the studies, there was a wide variation in the analytical methods used, especially with respect to the genetic polymorphisms of interest, environmental and lifestyle-related chemicals examined, and the study design used to estimate the gene-environment interactions. It was also found that a consistently increasing number of European and worldwide large-scale birth cohort studies on environmental health risks have been conducted since approximately 1996.

Conclusion

There is some evidence to suggest the importance of gene-environment interactions on adverse fetal growth. The current knowledge on gene-environment interactions will help guide future studies on the combined effects of maternal-child genetic polymorphisms and exposure to environmental and lifestyle-related chemicals during pregnancy.

Supplementary information

The online version contains supplementary material available at https://doi.org/10.1265/ehpm.21-00033.

Limited consumption of 100% fruit juices and sugar sweetened beverages in Japanese toddler and preschool children

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Low total 100% fruit juice and SSB intake for Japanese children.

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Comparable rates of beverage introduction for Japanese and North American children.

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Higher proportional dairy/milk drink consumption for Japanese than North American children.

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Low SSB consumption may contribute to lower obesity rate in Japanese children.

Japanese toddler and preschool children, ages 1.5–5 years, have lower rates of obesity, ≥95 th percentile body mass index, compared with North American ones. We examined parental reported beverage consumption patterns in 3 Japanese based mother-child cohorts from three different regions of Japan compared with data from cross-sectional and longitudinal studies from North America. Specifically, we used data from the Hamamatsu Birth Cohort for Mothers and Children (HBC Study) in Hamamatsu (Shizuoka Prefecture), the Seiiku Boshi Birth Cohort from Setagaya, Tokyo and the TMM BirThree Cohort Study from Miyagi. We additionally compared cross-sectional data from preschoolers from 24 prefectures in Japan as previously reported from a national study. While Japanese children had lower but comparable rates to North American children for introduction of sugar-sweetened beverages and 100% fruit juices, Japanese children consumed these beverages daily at a much lower level than North American children. Additionally, North American children may get more added sugars from soda and fruit juices as a relative percentage of total added sugar. By contrast, Japanese children consume more sweetened dairy drinks as a relative percentage of total added sugar. Sweetened dairy drinks may have the added benefits of including fats, calcium and probiotics which may be associated with lower risk for obesity compared with consumption of other types of sugar sweetened beverages.

Distinct temperament and character traits in patients with hyperemesis gravidarum

Hyperemesis gravidarum (HG) is an extreme form of vomiting during pregnancy and is characterized with excessive vomiting and nausea and ketonuria, electrolyte imbalance, dehydration and severe nurtition deficiency. The etiology of HG is considered as multifactorial. Altough there is a great interest to HG in terms of psychiatric conditions, there have been limited numbers of studies that researched personality traits in patients with HG. In present study, we aimed to compare temperament and character traits between pregnant women with and without HG by Temperament and Character Inventory. 48 pregnant women with HG and 64 healthy pregnant women were included to study. The HG groups and control group were compared in terms of temperament and character traits and anxiety levels. The temperament scores of novelty seeking, harm avoidance and reward dependence were found to be similar between groups while the score of persistence was significantly lower in HG group compared with control group (p = .021). All character scores in HG group as cooperativeness, self-directedness, and self-transcendence were significantly lower compared with control groups (respectively; p = .002, p = .018 and p = .029). The scores of STAI-1 was higher in HG group compared with control group (p = .027) whereas the score of STAI-2 was found to be similar between groups. Present study is the first to demonstrate different temperament and character traits in patients with HG. We argue that our results support the psychiatric background of HG; however further studies are needed to confirm our results.

Investigating the association between neuroticism and adverse obstetric and neonatal outcomes

Neuroticism is not only associated with affective disorders but also with certain somatic health problems. However, studies assessing whether neuroticism is associated with adverse obstetric or neonatal outcomes are scarce. This observational study comprises first-time mothers (n = 1969) with singleton pregnancies from several cohorts based in Uppsala, Sweden. To assess neuroticism-related personality, the Swedish universities Scales of Personality was used. Swedish national health registers were used to extract outcomes and confounders. In logistic regression models, odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for the outcomes by an increase of 63 units of neuroticism (equalling the interquartile range). Analyses were adjusted for maternal age, educational level, height, body mass index, year of delivery, smoking during pregnancy, involuntary childlessness, and psychiatric morbidity. Main outcomes were mode of delivery, gestational diabetes mellitus, gestational hypertension, preeclampsia, induction of delivery, prolonged delivery, severe lacerations, placental retention, postpartum haemorrhage, premature birth, infant born small or large for gestational age, and Apgar score. Neuroticism was not independently associated with adverse obstetric or neonatal outcomes besides gestational diabetes. For future studies, models examining sub-components of neuroticism or pregnancy-specific anxiety are encouraged.

Association between women's perceived ideal gestational weight gain during pregnancy and pregnancy outcomes

We aimed to clarify which beliefs motivate women to control their weight during pregnancy and how such values influence pregnancy outcomes. Using a questionnaire administered during mid- to late- pregnancy in a hospital-based prospective cohort study, we explored women’s perceived ideal GWG and their reasons for having this ideal. Using multivariate regression, we evaluated the association between women’s perceived ideal GWG and pregnancy outcomes. Among 1,691 normal and underweight women, the most common reason women thought avoiding excessive weight gain was important was “for ease of delivery and/or her health and well-being”. 912 (54%) women wished to maintain their GWG below 12 kg, the upper limit recommended by the Japanese governmental guidelines, and had a lower actual GWG compared to those who had less stringent notions of GWG. Compared to women whose perceived ideal GWG was 12 kg, those who considered their perceived limit to be lower had infants with lower birthweight on average despite no significant reduction in cesarean delivery rate or post-partum body weight retention. Our findings suggest that women who believe they should limit their weight gain to an amount lower than the upper limit of current guidelines succeeded in gaining significantly less weight but received no additional benefit.