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Abstract STUDY QUESTION To what extent is exposure to cellular telephones associated with male fertility? SUMMARY ANSWER Overall, we found little association between carrying a cell phone in the front pants pocket and male fertility, although among leaner men (BMI <25 kg/m2), carrying a cell phone in the front pants pocket was associated with lower fecundability. WHAT IS KNOWN ALREADY Some studies have indicated that cell phone use is associated with poor semen quality, but the results are conflicting. STUDY DESIGN, SIZE, DURATION Two prospective preconception cohort studies were conducted with men in Denmark (n = 751) and in North America (n = 2349), enrolled and followed via the internet from 2012 to 2020. PARTICIPANTS/MATERIALS, SETTING, METHODS On the baseline questionnaire, males reported their hours/day of carrying a cell phone in different body locations. We ascertained time to pregnancy via bi-monthly follow-up questionnaires completed by the female partner for up to 12 months or until reported conception. We used proportional probabilities regression models to estimate fecundability ratios (FRs) and 95% confidence intervals (CIs) for the association between male cell phone habits and fecundability, focusing on front pants pocket exposure, within each cohort separately and pooling across the cohorts using a fixed-effect meta-analysis. In a subset of participants, we examined selected semen parameters (semen volume, sperm concentration and sperm motility) using a home-based semen testing kit. MAIN RESULTS AND THE ROLE OF CHANCE There was little overall association between carrying a cell phone in a front pants pocket and fecundability: the FR for any front pants pocket exposure versus none was 0.94 (95% CI: 0.0.83–1.05). We observed an inverse association between any front pants pocket exposure and fecundability among men whose BMI was <25 kg/m2 (FR = 0.72, 95% CI: 0.59–0.88) but little association among men whose BMI was ≥25 kg/m2 (FR = 1.05, 95% CI: 0.90–1.22). There were few consistent associations between cell phone exposure and semen volume, sperm concentration, or sperm motility. LIMITATIONS, REASONS FOR CAUTION Exposure to radiofrequency radiation from cell phones is subject to considerable non-differential misclassification, which would tend to attenuate the estimates for dichotomous comparisons and extreme exposure categories (e.g. exposure 8 vs. 0 h/day). Residual confounding by occupation or other unknown or poorly measured factors may also have affected the results. WIDER IMPLICATIONS OF THE FINDINGS Overall, there was little association between carrying one’s phone in the front pants pocket and fecundability. There was a moderate inverse association between front pants pocket cell phone exposure and fecundability among men with BMI <25 kg/m2, but not among men with BMI ≥25 kg/m2. Although several previous studies have indicated associations between cell phone exposure and lower sperm motility, we found few consistent associations with any semen quality parameters. STUDY FUNDING/COMPETING INTEREST(S) The study was funded by the National Institutes of Health, grant number R03HD090315. In the last 3 years, PRESTO has received in-kind donations from Sandstone Diagnostics (for semen kits), Swiss Precision Diagnostics (home pregnancy tests), Kindara.com (fertility app), and FertilityFriend.com (fertility app). Dr. L.A.W. is a fibroid consultant for AbbVie, Inc. Dr. H.T.S. reports that the Department of Clinical Epidemiology is involved in studies with funding from various companies as research grants to and administered by Aarhus University. None of these studies are related to the current study. Dr. M.L.E. is an advisor to Sandstone Diagnostics, Ro, Dadi, Hannah, and Underdog. Dr. G.J.S. holds ownership in Sandstone Diagnostics Inc., developers of the Trak Male Fertility Testing System. In addition, Dr. G.J.S. has a patent pending related to Trak Male Fertility Testing System issued. TRIAL REGISTRATION NUMBER N/A
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Sensing the walking velocity of a person by using mobile devices
In an indoor space, determining a person’s speed of mobility has a lot of research significance and applicability in real-world scenarios. This research has developed a mobile application to investigate how to determine a person’s walking speed. The goal was to determine a person’s walking speed by using the number of steps. There has been similar work to test the accelerometer sensor in detecting steps. However, the accuracy of using the steps to calculate the velocity was not studied. This application uses the accelerometer sensor in the mobile device to detect steps and then compute the velocity. The accelerometer provides information about the user’s motion and acceleration, and an algorithm was developed to use that data to determine the steps. Once steps are determined, the person’s speed is calculated by using the change of location within a pre-determined space and time. Therefore, accurately measuring the number of steps was vital and it was determined that the position of the mobile device in the body plays a significant role in that accuracy. Therefore, the experiment used three device positions: the pants front pocket, the right hand, and the backpack. While walking, the number of steps were manually counted and recorded. A comparison was made between the recorded number of steps to the application’s measured steps. The experiment was conducted multiple times for each device position. The placement of the mobile devices in the front pants pocket gives the most accurate results, whereas the other two device positions gave reasonably accurate results. The position of the device played an important part in the research and had a significant impact on the accuracy of the results. In the future, testing can include additional device positions. Additionally, other mobile device sensors could be included in the testing and can be compared with this approach.
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- Award ID(s):
- 2131100
- PAR ID:
- 10354397
- Date Published:
- Journal Name:
- The Twenty-Sixth ACM Annual Consortium for Computing Sciences in Colleges Northeastern Conference
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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