Contraceptive Use Affects Overall Olfactory Performance: Investigation of Estradiol Dosage and Duration of Intake

<div><p>The influence of female sex steroids on cognitive performance and sensory perception has been investigated for decades. However, previous research that studied olfaction revealed inconsistent results. The main aim of this study was to investigate the effects of different ethinyl estradiol (EE) concentrations of oral contraceptives and duration of intake on olfactory function. Forty-two healthy women, with regular intake of either high or low EE dosage over at least one year and up to 15 years participated in this study. Results revealed a significant concordance between <i>a priori</i> categorization in the two groups with high and low EE dosage and data-driven hierarchical clustering (p = 0.008). Furthermore, significantly higher olfactory performance was observed in women using low-dose products compared to women using high-dosed products (p = 0.019). These findings indicate different effects of pill use with regard to EE concentration. We therefore strongly recommend the acquisition of information about EE dosage of oral contraceptives to reduce potential confounding factors when investigating sensory systems.</p></div

Detailed results of olfactory performance measures in the two groups of low (0.020mg EE) and high-dose (0.030mg EE) OCs and the control condition of women who do not take any OCs.

<p>Detailed results of olfactory performance measures in the two groups of low (0.020mg EE) and high-dose (0.030mg EE) OCs and the control condition of women who do not take any OCs.</p

Graphic representation of the correlation between overall olfactory performance (TDI score) and the duration of OC intake.

<p>High (circles) and low (triangles) estradiol dosage in OC products are presented separately. Lines mark the corresponding linear trend. This graph shows the interaction between EE dose and duration of intake. Each point in the plot represents the individual response of a participant in the olfactory performance assessment.</p

Cluster analysis.

<p>Agglomerative hierarchical cluster analysis for the whole data set to define the natural division of groups: Pairs of object were defined in the data set (for every subject: duration of intake and TDI score), then a similarity matrix representing every pair of objects of the data set was obtained and a hierarchical cluster tree was built by using the distance information. Clustering then was subsequently conducted by pruning the branches of the hierarchical tree based on the consistency criterion and two subclusters were obtained (cluster 1: marked with dots, cluster 2: marked with crosses).</p

Comparison of image quality at the thoracic outlet.

<p>Axial images with similar window setting (W900/L250) using the standard protocol and FBP (A) and at low-dose, using SAFIRE for image reconstruction (B). Both studies were rated having excellent diagnostic image quality. Higher vessel attenuation and reduced image noise is evident at low-dose and SAFIRE (B).</p

Results from group comparison of radiation dose (unpaired t-test).

<p>Data are means±standard deviations.</p><p>CDTI = Computed Tomography Dose Index (mGy); DLP = Dose Length Product (mGy*cm); ED = estimated effective dose (mSv).</p

CT study protocols and patient characteristics. Scan Range/Patients data presented as means±standard deviations (range).

<p>CT study protocols and patient characteristics. Scan Range/Patients data presented as means±standard deviations (range).</p

Box-Whisker plots of the estimated mean effective dose (mSv) for the study protocols.

<p>Box-Whisker plots of the estimated mean effective dose (mSv) for the study protocols.</p

Group comparison of objective image quality (mean vessel attenuation, muscle attenuation, background noise, CNR, SNR).

<p>Mixed model ANOVA was used for group comparison of objective image quality. Data are means±standard deviations.</p><p>HU = Houndsfield units, CNR = contrast-to-noise ratio, SNR = signal-to-noise ratio. BN = Standard deviation HU.</p><p>*BN at the level of the aorta = BN ACC.</p>†<p> = Significance level <0.05.</p

Ratings of the three applied substances CO₂, menthol and cinnamaldehyde.

<p>^a Bonferroni corrected</p><p>^b High values indicate pleasant/ familiar stimuli</p><p>^c High values indicate painful stimuli</p><p>^d Percentage of subjects who were able to label the substance correctly</p><p>Ratings of the three applied substances CO₂, menthol and cinnamaldehyde.</p