The effect of maternal hemoglobin concentration on fetal birth weight according to trimesters

To investigate the relationship between fetal birth weight and maternal hemoglobin concentrations in different trimesters.

This prospective cross-sectional study comprised 329 women, monitored and delivered between January 2013 and January 2014 in our clinic. Hemoglobin concentrations in all trimesters and all birth weights of the newborns were recorded. Comparisons and correlations were made of the maternal hemoglobin concentrations and birth weights in each trimester.

A positive correlation was determined between fetal weight and increased first trimester maternal hemoglobin concentration (p: 0.025). No correlation was found between fetal weights and second and third trimester hemoglobin concentrations (p = 0.287, p = 0.298, respectively). When the effect of independent factors on fetal weight was investigated, it was determined that birth week and first trimester hemoglobin levels were the factors of most influence.

Low hemoglobin concentrations in the first trimester of gestation seem to be associated with low fetal birth weights. Anemia can directly cause poor in utero fetal growth due to inadequate oxygen flow to the placental tissue or it can be an indirect indicator of maternal nutrition deficiency. In both circumstances, this study reveals that treatment of anemia before and in the early stages of pregnancy is directly correlated with better fetal outcomes.