End-tidal carbon monoxide measurements in women with pregnancy-induced hypertension and preeclampsia.
OBJECTIVE
We sought to compare the end-tidal carbon monoxide breath levels in pregnant women with and without pregnancy-induced hypertension and preeclampsia.


METHODS
We prospectively performed end-tidal carbon monoxide measurements corrected for ambient carbon monoxide in nonsmoking women during late gestation (>31 weeks). The study group included 22 women with pregnancy-induced hypertension or symptoms of preeclampsia and a control group of 20 normotensive pregnant women.


RESULTS
The carbon monoxide measurements corrected for ambient carbon monoxide (mean +/- SD) were significantly lower (P <.01) in the hypertensive group than in the control group (1.17 +/- 0.35 vs 1.70 +/- 0.54 ppm). The study group had a significantly higher number of low (<1.2 ppm) end-tidal carbon monoxide measurements corrected for ambient carbon monoxide (13 [59.1%] vs 1 [5.0%]; P <.001). The end-tidal carbon monoxide measurements corrected for ambient carbon monoxide remained significantly lower in comparison with those found in the control group when the study group was divided into women with pregnancy-induced hypertension only (n = 11) and those with preeclampsia (n = 11) (1.19 +/- 0.37 ppm; P <.01; and 1.15 +/- 0.41 ppm; P <.01; respectively).


CONCLUSIONS
Our findings suggest that carbon monoxide formation may be significantly lower in women with pregnancy-induced hypertension and preeclampsia. These data suggest that carbon monoxide could have a contributory role in the apparent paradox of the seemingly protective effect of smoking to decrease the risk of preeclampsia.
Baum
M
M
Department of Obstetrics and Gynecology, Chaim Sheba Medical Center of Tel-Hashomer, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
Schiff
E
E
Kreiser
D
D
Dennery
P A
PA
Stevenson
D K
DK
Rosenthal
T
T
Seidman
D S
DS
D000328:Adult; D002248:Carbon Monoxide; D005260:Female; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D011225:Pre-Eclampsia / Q000503:physiopathology*; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000503:physiopathology*; D011263:Pregnancy Trimester, Third; D011446:Prospective Studies; D012016:Reference Values; D013990:Tidal Volume
D002248:Carbon Monoxide