Related Experiment Video
Updated: Aug 19, 2026

Biochemical Measurement of Neonatal Hypoxia
Published on: August 24, 2011
Effects of carbon monoxide air pollution in pregnancy on neonatal nucleated red blood cells
Saeideh Ziaei1, Kobra Nouri, Anoshirvan Kazemnejad
1Faculty of Medical Science, Tarbiat Modarres University, Tehran, IR, Iran. Ziaei_99@yahoo.com
In an analytical cross-sectional study, the effects of carbon monoxide air pollution on carboxyhaemoglobin (COHb) and absolute nucleated red blood cells (nRBC) of the cord venous blood, were evaluated in 41 newborns delivered by caesarean section at term to mothers who had lived in an air-polluted area in the centre of Tehran during their pregnancies (study group). The parameters used were compared with 32 cord venous bloods of term caesarean-delivered newborns of mothers living in a healthy air area outside the city during their pregnancies. A significant difference was observed between the two groups in the cord COHb levels (mean +/- SD 10.51 +/- 4.79 vs. 1.58 +/- 0.96, P <0.001), cord nRBC (723.87 +/- 275.23 x 10(6)/L vs. 248.44 +/- 160.79 x 10(6)/L, P <0.001). A significant correlation was found between ambient carbon monoxide and cord COHb in the study and control groups, respectively (r=0.863, P=0.0001; r=0.691, P=0.0001), and also cord COHb and cord nRBC in the study group (r=0.360, P=0.01). Neonates born to mothers exposed to carbon monoxide air pollution had increased circulating absolute nRBC counts compared with those of the control group. We speculate that air pollution exposure in pregnancy should be avoided, because it may have negative effects on fetal oxygenation.
In an analytical cross-sectional study, the effects of carbon monoxide air pollution on carboxyhaemoglobin (COHb) and absolute nucleated red blood cells (nRBC) of the cord venous blood, were evaluated in 41 newborns delivered by caesarean section at term to mothers who had lived in an air-polluted area in the centre of Tehran during their pregnancies (study group). The parameters used were compared with 32 cord venous bloods of term caesarean-delivered newborns of mothers living in a healthy air area outside the city during their pregnancies. A significant difference was observed between the two groups in the cord COHb levels (mean +/- SD 10.51 +/- 4.79 vs. 1.58 +/- 0.96, P <0.001), cord nRBC (723.87 +/- 275.23 x 10(6)/L vs. 248.44 +/- 160.79 x 10(6)/L, P <0.001). A significant correlation was found between ambient carbon monoxide and cord COHb in the study and control groups, respectively (r=0.863, P=0.0001; r=0.691, P=0.0001), and also cord COHb and cord nRBC in the study group (r=0.360, P=0.01). Neonates born to mothers exposed to carbon monoxide air pollution had increased circulating absolute nRBC counts compared with those of the control group. We speculate that air pollution exposure in pregnancy should be avoided, because it may have negative effects on fetal oxygenation.
Related Concept Videos
Oxygen Transport in the Blood
Carbon Dioxide Transport in the Blood
Forms of CO2 Transport
1. Dissolved in plasma: A small percentage (7-10%) of CO2 is transported and dissolved directly in the plasma.
2. Carbaminohemoglobin: Just over 20% of CO2 is chemically bound to...
Hypoxia
Types of Hypoxia
There are four primary types of hypoxia, each resulting from a different cause:
1. Anemic hypoxia: This type occurs due to insufficient oxygen delivery caused by a lack of red blood cells (RBCs) or RBCs with abnormal or...
Hemoglobin
When all four heme groups are bound to oxygen, the resulting molecule is called oxyhemoglobin. As a result, arterial blood...
Factors Affecting Erythropoiesis
Several factors influence the erythrocyte production rate, with tissue oxygen level being among the most critical. Intense exercise or high altitudes can cause tissue hypoxia, which triggers the kidneys to release more erythropoietin (EPO) into the bloodstream.
EPO then...
Assessment of Diffusion and Perfusion
The Role of Diffusion in Respiration
Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration. In the respiratory system, this principle...

