The following is a summary of “Effects of menstrual cycle phase and ovulation on the salivary cortisol awakening response,” published in the February 2024 issue of Neurology by Haase, et al.

Several state and trait factors affect the cortisol waking reaction (CAR). For women, the periods may be one of these variables. Based on earlier research, it was suggested that the CAR is higher around ovulation. This is why it was suggested not to do any samples during this time. For a study, researchers sought to confirm earlier results that the CAR changes during the menstrual cycle, especially during ovulation, in two different studies. 

The first study looked at 27 healthy women who were naturally cycling. They took spit at 0, 30, 45, and 60 minutes after waking up on two days, during the follicular, ovulatory, and luteal stages. This was done using a method called “repeated measures.” In Study 2, CAR samples were taken from 30 healthy women who naturally cycled seven days in a row, right around when they were supposed to ovulate. To make the CAR measures more accurate, the subjects’ compliance with saliva sampling times was tracked, ovarian steroids (estradiol and progesterone) were collected, and test kits were used to prove ovulation. They were surprised that the CAR didn’t change during the menstrual cycle and that there wasn’t a significant link between changes in estradiol and progesterone. 

They also ruled out effects that could be confusing, like compliance, and made sure the cycle phase was correct. These findings show that the CAR is mostly resistant to hormone changes during the menstrual cycle, even when ovulation happens in the middle of the cycle. However, more study was needed to fully understand how ovarian steroids might change how the HPA axis works and how the menstrual cycle affects the amount of cortisol in saliva in psychobiological studies.

Source: sciencedirect.com/science/article/abs/pii/S0306453023006479