Maternal iron status in early pregnancy and birth outcomes

insights from the Baby's Vascular health and Iron in Pregnancy study

Nisreen A Alwan, Janet E Cade, Harry J McArdle, Darren C Greenwood, Helen E Hayes, Nigel A B Simpson

Research output: Contribution to journalArticle

37 Citations (Scopus)
4 Downloads (Pure)

Abstract

Fe deficiency anaemia during early pregnancy has been linked with low birth weight and preterm birth. However, this evidence comes mostly from studies measuring Hb levels rather than specific measures of Fe deficiency. The present study aimed to examine the association between maternal Fe status during the first trimester of pregnancy, as assessed by serum ferritin, transferrin receptor and their ratio, with size at birth and preterm birth. In the Baby VIP (Baby's Vascular health and Iron in Pregnancy) study, we recruited 362 infants and their mothers after delivery in Leeds, UK. Biomarkers were measured in maternal serum samples previously obtained in the first trimester of pregnancy. The cohort included sixty-four (18 %) small for gestational age (SGA) babies. Thirty-three babies were born preterm (9 %; between 34 and 37 weeks). First trimester maternal Fe depletion was associated with a higher risk of SGA (adjusted OR 2·2, 95 % CI 1·1, 4·1). This relationship was attenuated when including early pregnancy Hb in the model, suggesting it as a mediator (adjusted OR 1·6, 95 % CI 0·8, 3·2). For every 10 g/l increase in maternal Hb level in the first half of pregnancy the risk of SGA was reduced by 30 % (adjusted 95 % CI 0, 40 %); levels below 110 g/l were associated with a 3-fold increase in the risk of SGA (95 % CI 1·0, 9·0). There was no evidence of association between maternal Fe depletion and preterm birth (adjusted OR 1·5, 95 % 0·6, 3·8). The present study shows that depleted Fe stores in early pregnancy are associated with higher risk of SGA.

Original languageEnglish
Pages (from-to)1985-1992
Number of pages8
JournalBritish Journal of Nutrition
Volume113
Issue number12
Early online date6 May 2015
DOIs
Publication statusPublished - 28 Jun 2015

Fingerprint

Pregnancy Outcome
Blood Vessels
Iron
Gestational Age
Mothers
Parturition
Pregnancy
Premature Birth
First Pregnancy Trimester
Transferrin Receptors
Low Birth Weight Infant
Serum
Infant Health
Anemia
Biomarkers

Keywords

  • iron
  • birth weight
  • preterm birth
  • pregnancy

Cite this

Maternal iron status in early pregnancy and birth outcomes : insights from the Baby's Vascular health and Iron in Pregnancy study. / Alwan, Nisreen A; Cade, Janet E; McArdle, Harry J; Greenwood, Darren C; Hayes, Helen E; Simpson, Nigel A B.

In: British Journal of Nutrition, Vol. 113, No. 12, 28.06.2015, p. 1985-1992.

Research output: Contribution to journalArticle

Alwan, Nisreen A ; Cade, Janet E ; McArdle, Harry J ; Greenwood, Darren C ; Hayes, Helen E ; Simpson, Nigel A B. / Maternal iron status in early pregnancy and birth outcomes : insights from the Baby's Vascular health and Iron in Pregnancy study. In: British Journal of Nutrition. 2015 ; Vol. 113, No. 12. pp. 1985-1992.
@article{dc8fd7f28e4a40c28333e7867f4586fb,
title = "Maternal iron status in early pregnancy and birth outcomes: insights from the Baby's Vascular health and Iron in Pregnancy study",
abstract = "Fe deficiency anaemia during early pregnancy has been linked with low birth weight and preterm birth. However, this evidence comes mostly from studies measuring Hb levels rather than specific measures of Fe deficiency. The present study aimed to examine the association between maternal Fe status during the first trimester of pregnancy, as assessed by serum ferritin, transferrin receptor and their ratio, with size at birth and preterm birth. In the Baby VIP (Baby's Vascular health and Iron in Pregnancy) study, we recruited 362 infants and their mothers after delivery in Leeds, UK. Biomarkers were measured in maternal serum samples previously obtained in the first trimester of pregnancy. The cohort included sixty-four (18 {\%}) small for gestational age (SGA) babies. Thirty-three babies were born preterm (9 {\%}; between 34 and 37 weeks). First trimester maternal Fe depletion was associated with a higher risk of SGA (adjusted OR 2·2, 95 {\%} CI 1·1, 4·1). This relationship was attenuated when including early pregnancy Hb in the model, suggesting it as a mediator (adjusted OR 1·6, 95 {\%} CI 0·8, 3·2). For every 10 g/l increase in maternal Hb level in the first half of pregnancy the risk of SGA was reduced by 30 {\%} (adjusted 95 {\%} CI 0, 40 {\%}); levels below 110 g/l were associated with a 3-fold increase in the risk of SGA (95 {\%} CI 1·0, 9·0). There was no evidence of association between maternal Fe depletion and preterm birth (adjusted OR 1·5, 95 {\%} 0·6, 3·8). The present study shows that depleted Fe stores in early pregnancy are associated with higher risk of SGA.",
keywords = "iron, birth weight, preterm birth, pregnancy",
author = "Alwan, {Nisreen A} and Cade, {Janet E} and McArdle, {Harry J} and Greenwood, {Darren C} and Hayes, {Helen E} and Simpson, {Nigel A B}",
note = "Date of Acceptance: 16/03/2015 Acknowledgements N. A. A. was funded by a Wellcome Trust Research Training Fellowship (WT87789). H. J. M. and H. E. H. are supported by the Scottish Government’s Rural and Environment Science and Analytical Services. N. A. B. S. is supported by Cerebra. The authors’ contributions are as follows: N. A. A. was responsible for organising the study conduct, data collection and database management, performed the statistical analysis, interpreted the results and drafted the paper. N. A. A., N. A. B. S., J. E. C., H. J. M. and D. C. G. contributed to the study concept and design, and interpretation of results. H. J. M. and H. E. H. analysed the laboratory samples. J. E. C. and D. C. G. provided advice on statistical strategy and analysis. All authors have fully participated in the reporting stage and have critically reviewed and approved the final draft of the paper. The authors declare no conflict of interest",
year = "2015",
month = "6",
day = "28",
doi = "10.1017/S0007114515001166",
language = "English",
volume = "113",
pages = "1985--1992",
journal = "British Journal of Nutrition",
issn = "0007-1145",
publisher = "Cambridge Univ. Press.",
number = "12",

}

TY - JOUR

T1 - Maternal iron status in early pregnancy and birth outcomes

T2 - insights from the Baby's Vascular health and Iron in Pregnancy study

AU - Alwan, Nisreen A

AU - Cade, Janet E

AU - McArdle, Harry J

AU - Greenwood, Darren C

AU - Hayes, Helen E

AU - Simpson, Nigel A B

N1 - Date of Acceptance: 16/03/2015 Acknowledgements N. A. A. was funded by a Wellcome Trust Research Training Fellowship (WT87789). H. J. M. and H. E. H. are supported by the Scottish Government’s Rural and Environment Science and Analytical Services. N. A. B. S. is supported by Cerebra. The authors’ contributions are as follows: N. A. A. was responsible for organising the study conduct, data collection and database management, performed the statistical analysis, interpreted the results and drafted the paper. N. A. A., N. A. B. S., J. E. C., H. J. M. and D. C. G. contributed to the study concept and design, and interpretation of results. H. J. M. and H. E. H. analysed the laboratory samples. J. E. C. and D. C. G. provided advice on statistical strategy and analysis. All authors have fully participated in the reporting stage and have critically reviewed and approved the final draft of the paper. The authors declare no conflict of interest

PY - 2015/6/28

Y1 - 2015/6/28

N2 - Fe deficiency anaemia during early pregnancy has been linked with low birth weight and preterm birth. However, this evidence comes mostly from studies measuring Hb levels rather than specific measures of Fe deficiency. The present study aimed to examine the association between maternal Fe status during the first trimester of pregnancy, as assessed by serum ferritin, transferrin receptor and their ratio, with size at birth and preterm birth. In the Baby VIP (Baby's Vascular health and Iron in Pregnancy) study, we recruited 362 infants and their mothers after delivery in Leeds, UK. Biomarkers were measured in maternal serum samples previously obtained in the first trimester of pregnancy. The cohort included sixty-four (18 %) small for gestational age (SGA) babies. Thirty-three babies were born preterm (9 %; between 34 and 37 weeks). First trimester maternal Fe depletion was associated with a higher risk of SGA (adjusted OR 2·2, 95 % CI 1·1, 4·1). This relationship was attenuated when including early pregnancy Hb in the model, suggesting it as a mediator (adjusted OR 1·6, 95 % CI 0·8, 3·2). For every 10 g/l increase in maternal Hb level in the first half of pregnancy the risk of SGA was reduced by 30 % (adjusted 95 % CI 0, 40 %); levels below 110 g/l were associated with a 3-fold increase in the risk of SGA (95 % CI 1·0, 9·0). There was no evidence of association between maternal Fe depletion and preterm birth (adjusted OR 1·5, 95 % 0·6, 3·8). The present study shows that depleted Fe stores in early pregnancy are associated with higher risk of SGA.

AB - Fe deficiency anaemia during early pregnancy has been linked with low birth weight and preterm birth. However, this evidence comes mostly from studies measuring Hb levels rather than specific measures of Fe deficiency. The present study aimed to examine the association between maternal Fe status during the first trimester of pregnancy, as assessed by serum ferritin, transferrin receptor and their ratio, with size at birth and preterm birth. In the Baby VIP (Baby's Vascular health and Iron in Pregnancy) study, we recruited 362 infants and their mothers after delivery in Leeds, UK. Biomarkers were measured in maternal serum samples previously obtained in the first trimester of pregnancy. The cohort included sixty-four (18 %) small for gestational age (SGA) babies. Thirty-three babies were born preterm (9 %; between 34 and 37 weeks). First trimester maternal Fe depletion was associated with a higher risk of SGA (adjusted OR 2·2, 95 % CI 1·1, 4·1). This relationship was attenuated when including early pregnancy Hb in the model, suggesting it as a mediator (adjusted OR 1·6, 95 % CI 0·8, 3·2). For every 10 g/l increase in maternal Hb level in the first half of pregnancy the risk of SGA was reduced by 30 % (adjusted 95 % CI 0, 40 %); levels below 110 g/l were associated with a 3-fold increase in the risk of SGA (95 % CI 1·0, 9·0). There was no evidence of association between maternal Fe depletion and preterm birth (adjusted OR 1·5, 95 % 0·6, 3·8). The present study shows that depleted Fe stores in early pregnancy are associated with higher risk of SGA.

KW - iron

KW - birth weight

KW - preterm birth

KW - pregnancy

U2 - 10.1017/S0007114515001166

DO - 10.1017/S0007114515001166

M3 - Article

VL - 113

SP - 1985

EP - 1992

JO - British Journal of Nutrition

JF - British Journal of Nutrition

SN - 0007-1145

IS - 12

ER -