Table 2.

Characteristics of the included studies: Male and Female.

References	Title	Study Design	Sample size & Age	Duration of infertility	Inclusion criteria	Cause(s) of infertility	Methods of cortisol measurement	Day, time and types of biological sample collected	Methods & Results	Conclusion
(21)	Stress in couples undergoing assisted reproductive technology	Prospective study	150 patients/75 couples (Mean age, female pregnant: 30.9 ± 4.9, male pregnant: 32.2 ± 4.1, female not pregnant: 33.9 ± 3.9, male not pregnant: 35.3 ± 3.5 years)	From 5.5 ± 3.5 to 5.5 ± 2.4 years	Couples with primary infertility in their first ART treatment cycle, with a BMI of 20.0–29.9 kg/m2.	Primary infertility, female factor: endometriosis, ovulatory disorders, and poor ovarian reserve, and tubal factor Male factor: based on WHO criteria (2010)	Cortisol level was measure using enzyme-linked immunosorbent assay.	Saliva; collected at 15, 30, and 60 min upon waking up prior to the start of gonadotropins in GnRH antagonist cycle (first day of their ART cycle)	There was no significant difference in cortisol levels between different interval upon waking up (15, 30, and 60 mins) in male and female samples. The median value of cortisol level was significantly higher in women who became pregnant than those who did not [24.7 ng/ml (19.9–63.1) vs. 20.7 (10.4–30.4), respectively]. No significant difference was seen in the cortisol level of male between the two groups.	Based on the interval after waking up, the study discovered no statistically significant variation in cortisol levels. However, pregnant women's cortisol levels were higher than those of non-pregnant women, while no such difference was seen in males.