Abstract
Background: Interpretation of observational studies on associations between prefrontal cognitive functioning and hormone levels across the female menstrual cycle is complicated due to small sample sizes and poor replicability.Methods: This observational multisite study comprised data of n = 88 menstruating women from Hannover, Germany, and Zurich, Switzerland, assessed during a first cycle and n = 68 re-assessed during a second cycle to rule out practice effects and false-positive chance findings. We assessed visuospatial working memory, attention, cognitive bias and hormone levels at four consecutive time-points across both cycles. In addition to inter-individual differences we examined intra-individual change over time (i.e., within-subject effects).Results: Estrogen, progesterone and testosterone did not relate to inter-individual differences in cognitive functioning. There was a significant negative association between intra-individual change in progesterone and change in working memory from pre-ovulatory to mid-luteal phase during the first cycle, but that association did not replicate in the second cycle. Intra-individual change in testosterone related negatively to change in cognitive bias from menstrual to pre-ovulatory as well as from pre-ovulatory to mid-luteal phase in the first cycle, but these associations did not replicate in the second cycle.Conclusions: There is no consistent association between women's hormone levels, in particular estrogen and progesterone, and attention, working memory and cognitive bias. That is, anecdotal findings observed during the first cycle did not replicate in the second cycle, suggesting that these are false-positives attributable to random variation and systematic biases such as practice effects. Due to methodological limitations, positive findings in the published literature must be interpreted with reservation.
Highlights
In the scientific literature, female sex hormones and the menstrual cycle have been linked to cognitive performance (Farage et al, 2008; Sherwin, 2012)
A detailed account of the exact number of assays at each cycle phase, range, means and standard deviations for all hormone measures is provided in the Supplementary Table 1
As there was no evidence for any consistent association between sex hormones and prefrontal cognitive functions across both cycles, for the sake of parsimony, here we report the results for estrogen only
Summary
Female sex hormones and the menstrual cycle have been linked to cognitive performance (Farage et al, 2008; Sherwin, 2012). There are growing concerns that various positive associations reported in the literature could be true null associations, that is, methodological artifacts and chance findings (Ioannidis, 2005; Rosmalen and Oldehinkel, 2011; Ferguson and Heene, 2012; Hengartner, 2017) In support of this notion it has been demonstrated that due to scientific biases, first, false-positive findings are ubiquitous, second, that inflated effect sizes are common and, third, that the reproducibility of results is generally low in psychological and biomedical research (e.g., Kriegeskorte et al, 2009; Prinz et al, 2011; Ritchie et al, 2012; Button et al, 2013; Macleod et al, 2014; Open Science Collaboration, 2015; Muller et al, 2017). Interpretation of observational studies on associations between prefrontal cognitive functioning and hormone levels across the female menstrual cycle is complicated due to small sample sizes and poor replicability
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
