The Associations of Maternal Hemoglobin Concentration in Different Time Points and Its Changes during Pregnancy with Birth Weight Outcomes

Abstract

Maternal hemoglobin (Hb) is related to nutritional status, which affects neonatal birth weight. However, it is very common for maternal Hb to fluctuate during pregnancy. To evaluate the associations of maternal Hb in different time points and its changes during pregnancy with neonatal birth weight, small for gestational age (SGA)/low birth weight (LBW) and large for gestational age (LGA)/macrosomia, we conducted this study by using data from the Electronic Medical Record System (EMRS) database of Zhoushan Maternal and Child Care Hospital in Zhejiang province, China. The pregnancy was divided into five periods: first, early-second, mediate-second, late-second, early-third and late-third trimesters; we further calculated the maternal Hb changes during pregnancy. Overall, the socio-demographic characteristics, health-related information and childbirth-related information of 24,183 mother–infant pairs were obtained. The average Hb concentration during the different periods were 123.95 ± 10.14, 117.95 ± 9.84, 114.31 ± 9.03, 113.26 ± 8.82, 113.29 ± 8.68 and 115.01 ± 8.85 g/L, respectively. Significant dose–response relationships between maternal Hb and birth weight were observed in the first, late-second and later trimesters (p non-linear < 0.05). Maternal Hb < 100 g/L was related to a high risk of LGA/macrosomia in the late-second (OR: 1.47, 95% CI: 1.18, 1.83) and later trimesters; additionally, high maternal Hb (>140 g/L) increased the risk of SGA/LBW in the first (OR: 1.26, 95% CI: 1.01, 1.57) and late-third trimesters (OR: 1.96, 95% CI: 1.20, 3.18). In addition, the increase in maternal Hb from the late-second to late-third trimesters had a positive correlation with SGA/LBW. In conclusion, maternal Hb markedly fluctuated during pregnancy; the negative dose–response association of maternal Hb in the late-second and third trimesters, and Hb change during pregnancy with neonatal birth weight outcomes were observed, respectively. Furthermore, the phenomenon of high Hb in the first trimester and after the late-second trimester and the increase of maternal Hb from the late-second to late-third trimesters more significantly increasing the risk of SGA/LBW should especially be given more attention. Its biological mechanism needs to be further explored.

The associations of maternal liver biomarkers in early pregnancy with the risk of gestational diabetes mellitus: a prospective cohort study and Mendelian randomization analysis

“…A logistic regression model was used to assess the association of LFI in early pregnancy and the risk of GDM. Covariates were selected based on previous investigations ( 19 ), which included maternal age, BMI in the first trimester, educational level, gravidity, parity, weight gain before OGTT, gestational age of measurement, smoking status, and drinking consumption. Because BMI was included in the calculation of HSI, BMI was treated as a categorical variable (< 18.5, 18.5-23.9, 24.0-27.9, and ≥ 28) other than a continuous variable when testing the association between HSI and GDM.…”

Breastfeeding, Gestational Diabetes Mellitus, Size at Birth and Overweight/Obesity in Early Childhood

“…Data were extracted from the comprehensive electronic medical record system (EMRS) of Zhoushan Maternal and Child Care Hospital, Zhejiang Province, China from 2012 to 2021. The EMRS was a municipal system established in 2001 and included information on the health care of all pregnant women and newborns in Zhoushan city after 2011 [17,18]. Briefly, according to the guidelines of Zhoushan Maternal and Child Care Hospital, the information on pregnant women was recorded in the EMRS at each regular antenatal visit, during delivery, and postpartum.…”

A Prospective Study to Assess the Correlation of Neonatal Birth Weight with the Hemoglobin Level of the Mother During Pregnancy

“…An adequate increase in Hb also increases birth weight [9]. Low birth weight and small for gestational age babies are affected by the deficiency of iron in the mother [10].…”