Hyperosmia is suspected in pregnancy; however, no empirical study using 
validated measures of olfactory function has clearly confirmed the anecdotal 
reports of this phenomenon. The goal of the current study is to compare the 
olfactory sensitivity of pregnant women to that of nonpregnant women and men. 
All participants rated their sense of smell and pregnant women listed the odors 
to which they were most sensitive. Detection thresholds were measured using a 
well-validated protocol. A group of pregnant and nonpregnant women was studied 
longitudinally using a signal detection procedure designed to detect small 
differences in sensitivity. Pregnant women, particularly in the 1st trimester, 
rated their sense of smell to be higher than nonpregnant women and men and 
indicated many (primarily unpleasant) odors to which they were more sensitive. 
Women rated their sense of smell higher than men. However, there was no sex 
difference in thresholds and neither thresholds nor signal detection measures of 
sensitivity were significantly affected by either sex or pregnancy status. The 
implications of the lack of relationship between self-report and measures of 
olfactory sensitivity, particularly in pregnancy, are discussed.