Experimental Study on the Effects of Acute Carbon Monoxide Intoxication during Pregnancy on Fetal Growth in Rat

Abstract

This study was carried out to observe the effect of acute carbon monoxide (CO) poisoning on the gestational process and outcome, and to develop the proper method to evaluate it Primiparous Sprague-Dawley rats were exposed for 1 hour to a CO of 1800 ppm or 2 hours to a CO of 1400 ppm resulting in blood carboxyhemoglobin levels of 68-72% on day 11 of gestation when active organogenesis is beginning. Half the rats exposed to a CO of 1400 ppm for 2 hours were treated with hyperbaric oxygen (HBO) 15 minutes after CO exposure. Only the group exposed to a CO of 1400 ppm for 2 hours sustained significant damage to the pregnancy. Though no significant pregnancy interruption resulted in the group exposed to CO at a concentration of 1800 ppm for 1 hour, the fetal growth were significantly retarded. The fetuses of rats treated with HBO after exposure to CO did not show growth retardation other than a decrease in the ratio of biparietal diameter to crown-rump length. Carbon monoxide was not found to be teratogenic in any experimental groups.