The cortisol awakening response (CAR) across the female menstrual cycle.

The cortisol awakening response (CAR) has been established as a useful marker of hypothalamus-pituitary-adrenal (HPA) axis activity and has become a standard tool for stress research in ambulatory settings. Although much knowledge has been accumulated on a variety of factors modulating the CAR, the impact of the female menstrual cycle, especially during ovulation, still remains unclear. To the best of our knowledge, this is the first study that measured the CAR during menses, the follicular phase, ovulation and the luteal phase in a repeated measurement design. For this purpose, a final sample of 29 naturally cycling, healthy, non-smoking, and medication-free women collected saliva samples directly after awakening as well as 30, 45, and 60 min later during each of the four different phases. To determine the timing of ovulation, an ambulatory chromatographic ovulation test kit was applied. A repeated measurements ANOVA resulted in a significant interaction effect sample × cycle phase (p=0.04), with the highest awakening response during ovulation. While awakening cortisol levels were comparable across the four cycle phases (p=n.s.), the net increase was significantly elevated during ovulation (p=0.05). Our data also confirmed earlier cross-sectional results reporting no differences in the CAR between the follicular and luteal phase. Finally, a concurrent assessment of mood applying the POMS (Profile of Mood States) yielded no differences across the four cycle phases (all p=n.s.). In sum, the present data points to the idea that the CAR is elevated during ovulation, an effect which is presumably mediated by elevated sex steroid levels during the ovulation period.

Wolfram M ，Bellingrath S ，Kudielka BM 《-》

Effects of menstrual cycle phase and ovulation on the salivary cortisol awakening response.

The cortisol awakening response (CAR) is influenced by several state and trait variables, one of which might be the menstrual cycle in women. Previous results suggested that the CAR is enhanced around ovulation, which is why it has been recommended to avoid sampling during the ovulatory phase. In two separate studies, we aimed to replicate previous findings that reported the CAR's modulation across the menstrual cycle, especially during ovulation. In Study 1, a group of 27 healthy naturally cycling women collected saliva at 0, 30, 45, and 60 min post-awakening on two days during their follicular, ovulatory, and luteal phases in a repeated measures design. In Study 2, CAR samples were collected from 30 healthy naturally cycling women on seven consecutive days around the expected ovulation. To increase reliability of CAR measurements, participants' compliance of saliva sampling times was monitored, ovarian steroids (estradiol and progesterone) were collected, and ovulation was confirmed with specific test kits. Contrary to our expectations, we detected no differences in the CAR over the menstrual cycle, and no significant association with variations in estradiol and progesterone. In addition, we excluded confounding effects such as compliance and validated the cycle phase. These results suggest that the CAR is largely robust against hormonal variations across the menstrual cycle, including the mid-cycle phase around ovulation. However, further research is needed to understand the potential ovarian steroid-induced modulation of HPA axis functioning and the menstrual cycle's effects on salivary cortisol levels in psychobiological studies.

Haase L ，Vehlen A ，Strojny J ，Domes G ... -  《-》

No effects of repeated forced wakings during three consecutive nights on morning cortisol awakening responses (CAR): a preliminary study.

Dettenborn L ，Rosenloecher F ，Kirschbaum C 《-》

Evidence for altered hypothalamus-pituitary-adrenal axis functioning in systemic hypertension: blunted cortisol response to awakening and lower negative feedback sensitivity.

Wirtz PH ，von Känel R ，Emini L ，Ruedisueli K ，Groessbauer S ，Maercker A ，Ehlert U ... -  《PSYCHONEUROENDOCRINOLOGY》

Awakening responses and diurnal fluctuations of salivary cortisol, DHEA-S and α-amylase in healthy male subjects.

Ghiciuc CM ，Cozma-Dima CL ，Pasquali V ，Renzi P ，Simeoni S ，Lupusoru CE ，Patacchioli FR ... -  《-》