Association between blood manganese level during pregnancy and birth size: The Japan environment and children's study (JECS)

The Japan Environment and Children's Study Group

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Background: Manganese (Mn) is both an essential element and a potential toxicant. Although a few studies have suggested a nonlinear relationship between the maternal whole blood Mn level at delivery and infant birth weight, little is known about the effects of Mn levels during pregnancy on fetal growth, particularly with regard to sex-specific differences. Methods: In this nationwide birth cohort study, we examined the association of maternal blood Mn level during pregnancy with infant birth weight, length, and head circumference in 16,473 mother–infant pairs. Pregnant women living in 15 regions across Japan were recruited between January 2011 and March 2014. The analysis of birth size (8,484 males and 7,989 females) was conducted using a nonlinear spline, followed by the use of quadratic regression or linear regression models. The analysis of small-for-gestational-age (SGA) (6,962 males and 6,528 females born vaginally) was conducted using multivariate logistic regression. Additionally, subgroup analysis was conducted according to the timing of blood sampling. Results: The median maternal blood Mn level during pregnancy (i.e., 2nd and 3rd trimesters) was 16.2 µg/L (range, 4.3–44.5 µg/L). A positive linear association between the log blood Mn level and head circumference was observed in both male and female infants. However, a nonlinear relationship between the log blood Mn level and birth weight was observed only in male infants, such that the birth weight increased up to a blood Mn level of 18.6 µg/L. In the subgroup analysis stratified by the timing of maternal blood sampling, this nonlinear relationship was obvious only when sampling was performed in the 3rd trimester. Male infants in the lowest blood Mn level quartile (≤ 13.2 µg/L) faced an increased risk of SGA (odds ratio [95% confidence interval] = 1.35 [1.04–1.74]), as did those in the highest blood Mn level quartile (≥ 21.0 µg/L) when sampling was performed during the 3rd trimester (odds ratio [95% confidence interval] = 1.62 [1.10 to 2.39]), compared to those in the third blood Mn level quartile (the category including 18.6 µg/L). No association of blood Mn level with birth weight was observed among female infants, and blood Mn level was not associated with birth length in either male or female infants. Conclusion: A low blood Mn level during pregnancy or a high blood Mn level during the 3rd trimester was associated with a lower birth weight and increased risk of SGA in male infants, but not in female infants. A low blood Mn level was found to correlate slightly with a small head circumference among infants of both sexes.

Original languageEnglish
Pages (from-to)117-126
Number of pages10
JournalEnvironmental Research
DOIs
Publication statusPublished - 2019 May 1

Fingerprint

Manganese
pregnancy
manganese
Japan
Blood
blood
Parturition
Pregnancy
Birth Weight
Mothers
Sampling
Gestational Age
Head
sampling
confidence interval
Linear Models
Odds Ratio
infant
Confidence Intervals
Fetal Development

Keywords

  • birth size
  • manganese
  • pregnancy
  • sex difference
  • SGA

ASJC Scopus subject areas

  • Biochemistry
  • Environmental Science(all)

Cite this

Association between blood manganese level during pregnancy and birth size : The Japan environment and children's study (JECS). / The Japan Environment and Children's Study Group.

In: Environmental Research, 01.05.2019, p. 117-126.

Research output: Contribution to journalArticle

@article{d3cf96ebbe2248dea09e620d861c1f7e,
title = "Association between blood manganese level during pregnancy and birth size: The Japan environment and children's study (JECS)",
abstract = "Background: Manganese (Mn) is both an essential element and a potential toxicant. Although a few studies have suggested a nonlinear relationship between the maternal whole blood Mn level at delivery and infant birth weight, little is known about the effects of Mn levels during pregnancy on fetal growth, particularly with regard to sex-specific differences. Methods: In this nationwide birth cohort study, we examined the association of maternal blood Mn level during pregnancy with infant birth weight, length, and head circumference in 16,473 mother–infant pairs. Pregnant women living in 15 regions across Japan were recruited between January 2011 and March 2014. The analysis of birth size (8,484 males and 7,989 females) was conducted using a nonlinear spline, followed by the use of quadratic regression or linear regression models. The analysis of small-for-gestational-age (SGA) (6,962 males and 6,528 females born vaginally) was conducted using multivariate logistic regression. Additionally, subgroup analysis was conducted according to the timing of blood sampling. Results: The median maternal blood Mn level during pregnancy (i.e., 2nd and 3rd trimesters) was 16.2 µg/L (range, 4.3–44.5 µg/L). A positive linear association between the log blood Mn level and head circumference was observed in both male and female infants. However, a nonlinear relationship between the log blood Mn level and birth weight was observed only in male infants, such that the birth weight increased up to a blood Mn level of 18.6 µg/L. In the subgroup analysis stratified by the timing of maternal blood sampling, this nonlinear relationship was obvious only when sampling was performed in the 3rd trimester. Male infants in the lowest blood Mn level quartile (≤ 13.2 µg/L) faced an increased risk of SGA (odds ratio [95{\%} confidence interval] = 1.35 [1.04–1.74]), as did those in the highest blood Mn level quartile (≥ 21.0 µg/L) when sampling was performed during the 3rd trimester (odds ratio [95{\%} confidence interval] = 1.62 [1.10 to 2.39]), compared to those in the third blood Mn level quartile (the category including 18.6 µg/L). No association of blood Mn level with birth weight was observed among female infants, and blood Mn level was not associated with birth length in either male or female infants. Conclusion: A low blood Mn level during pregnancy or a high blood Mn level during the 3rd trimester was associated with a lower birth weight and increased risk of SGA in male infants, but not in female infants. A low blood Mn level was found to correlate slightly with a small head circumference among infants of both sexes.",
keywords = "birth size, manganese, pregnancy, sex difference, SGA",
author = "{The Japan Environment and Children's Study Group} and Midori Yamamoto and Kenichi Sakurai and Akifumi Eguchi and Shin Yamazaki and Nakayama, {Shoji F.} and Tomohiko Isobe and Ayano Takeuchi and Tosiya Sato and Akira Hata and Chisato Mori and Hiroshi Nitta and Yukihiro Ohya and Reiko Kishi and Nobuo Yaegashi and Koichi Hashimoto and Shuichi Ito and Zentaro Yamagata and Hidekuni Inadera and Michihiro Kamijima and Takeo Nakayama and Hiroyasu Iso and Masayuki Shima and Yasuaki Hirooka and Narufumi Suganuma and Koichi Kusuhara and Takahiko Katoh",
year = "2019",
month = "5",
day = "1",
doi = "10.1016/j.envres.2019.02.007",
language = "English",
pages = "117--126",
journal = "Environmental Research",
issn = "0013-9351",
publisher = "Academic Press Inc.",

}

TY - JOUR

T1 - Association between blood manganese level during pregnancy and birth size

T2 - The Japan environment and children's study (JECS)

AU - The Japan Environment and Children's Study Group

AU - Yamamoto, Midori

AU - Sakurai, Kenichi

AU - Eguchi, Akifumi

AU - Yamazaki, Shin

AU - Nakayama, Shoji F.

AU - Isobe, Tomohiko

AU - Takeuchi, Ayano

AU - Sato, Tosiya

AU - Hata, Akira

AU - Mori, Chisato

AU - Nitta, Hiroshi

AU - Ohya, Yukihiro

AU - Kishi, Reiko

AU - Yaegashi, Nobuo

AU - Hashimoto, Koichi

AU - Ito, Shuichi

AU - Yamagata, Zentaro

AU - Inadera, Hidekuni

AU - Kamijima, Michihiro

AU - Nakayama, Takeo

AU - Iso, Hiroyasu

AU - Shima, Masayuki

AU - Hirooka, Yasuaki

AU - Suganuma, Narufumi

AU - Kusuhara, Koichi

AU - Katoh, Takahiko

PY - 2019/5/1

Y1 - 2019/5/1

N2 - Background: Manganese (Mn) is both an essential element and a potential toxicant. Although a few studies have suggested a nonlinear relationship between the maternal whole blood Mn level at delivery and infant birth weight, little is known about the effects of Mn levels during pregnancy on fetal growth, particularly with regard to sex-specific differences. Methods: In this nationwide birth cohort study, we examined the association of maternal blood Mn level during pregnancy with infant birth weight, length, and head circumference in 16,473 mother–infant pairs. Pregnant women living in 15 regions across Japan were recruited between January 2011 and March 2014. The analysis of birth size (8,484 males and 7,989 females) was conducted using a nonlinear spline, followed by the use of quadratic regression or linear regression models. The analysis of small-for-gestational-age (SGA) (6,962 males and 6,528 females born vaginally) was conducted using multivariate logistic regression. Additionally, subgroup analysis was conducted according to the timing of blood sampling. Results: The median maternal blood Mn level during pregnancy (i.e., 2nd and 3rd trimesters) was 16.2 µg/L (range, 4.3–44.5 µg/L). A positive linear association between the log blood Mn level and head circumference was observed in both male and female infants. However, a nonlinear relationship between the log blood Mn level and birth weight was observed only in male infants, such that the birth weight increased up to a blood Mn level of 18.6 µg/L. In the subgroup analysis stratified by the timing of maternal blood sampling, this nonlinear relationship was obvious only when sampling was performed in the 3rd trimester. Male infants in the lowest blood Mn level quartile (≤ 13.2 µg/L) faced an increased risk of SGA (odds ratio [95% confidence interval] = 1.35 [1.04–1.74]), as did those in the highest blood Mn level quartile (≥ 21.0 µg/L) when sampling was performed during the 3rd trimester (odds ratio [95% confidence interval] = 1.62 [1.10 to 2.39]), compared to those in the third blood Mn level quartile (the category including 18.6 µg/L). No association of blood Mn level with birth weight was observed among female infants, and blood Mn level was not associated with birth length in either male or female infants. Conclusion: A low blood Mn level during pregnancy or a high blood Mn level during the 3rd trimester was associated with a lower birth weight and increased risk of SGA in male infants, but not in female infants. A low blood Mn level was found to correlate slightly with a small head circumference among infants of both sexes.

AB - Background: Manganese (Mn) is both an essential element and a potential toxicant. Although a few studies have suggested a nonlinear relationship between the maternal whole blood Mn level at delivery and infant birth weight, little is known about the effects of Mn levels during pregnancy on fetal growth, particularly with regard to sex-specific differences. Methods: In this nationwide birth cohort study, we examined the association of maternal blood Mn level during pregnancy with infant birth weight, length, and head circumference in 16,473 mother–infant pairs. Pregnant women living in 15 regions across Japan were recruited between January 2011 and March 2014. The analysis of birth size (8,484 males and 7,989 females) was conducted using a nonlinear spline, followed by the use of quadratic regression or linear regression models. The analysis of small-for-gestational-age (SGA) (6,962 males and 6,528 females born vaginally) was conducted using multivariate logistic regression. Additionally, subgroup analysis was conducted according to the timing of blood sampling. Results: The median maternal blood Mn level during pregnancy (i.e., 2nd and 3rd trimesters) was 16.2 µg/L (range, 4.3–44.5 µg/L). A positive linear association between the log blood Mn level and head circumference was observed in both male and female infants. However, a nonlinear relationship between the log blood Mn level and birth weight was observed only in male infants, such that the birth weight increased up to a blood Mn level of 18.6 µg/L. In the subgroup analysis stratified by the timing of maternal blood sampling, this nonlinear relationship was obvious only when sampling was performed in the 3rd trimester. Male infants in the lowest blood Mn level quartile (≤ 13.2 µg/L) faced an increased risk of SGA (odds ratio [95% confidence interval] = 1.35 [1.04–1.74]), as did those in the highest blood Mn level quartile (≥ 21.0 µg/L) when sampling was performed during the 3rd trimester (odds ratio [95% confidence interval] = 1.62 [1.10 to 2.39]), compared to those in the third blood Mn level quartile (the category including 18.6 µg/L). No association of blood Mn level with birth weight was observed among female infants, and blood Mn level was not associated with birth length in either male or female infants. Conclusion: A low blood Mn level during pregnancy or a high blood Mn level during the 3rd trimester was associated with a lower birth weight and increased risk of SGA in male infants, but not in female infants. A low blood Mn level was found to correlate slightly with a small head circumference among infants of both sexes.

KW - birth size

KW - manganese

KW - pregnancy

KW - sex difference

KW - SGA

UR - http://www.scopus.com/inward/record.url?scp=85061639835&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85061639835&partnerID=8YFLogxK

U2 - 10.1016/j.envres.2019.02.007

DO - 10.1016/j.envres.2019.02.007

M3 - Article

C2 - 30782531

AN - SCOPUS:85061639835

SP - 117

EP - 126

JO - Environmental Research

JF - Environmental Research

SN - 0013-9351

ER -