Table 4.

Limitations of existing literature and recommendations for future research.

Limitation	Recommendation (s)
Variation in operationalization of stress	Further precision in conceptualization and measurement of stress Evaluate potential differences by type of stress and synergistic effects of different types of stress across developmental periods
Measurements of cortisol limited to one day, only one sample per day, or one gestational assessment	Repeated sampling of cortisol across multiple days and gestational timepoints to increase precision and account for changes in cortisol indices across pregnancy
Measurements of stress limited to one gestational assessment	Repeated measures of stress across gestation to account for changes in stress and/or perceptions of stress across pregnancy that may show distinct links with cortisol
Variation in covariates included (if any) in analytic models	Statistically controlling for confounding factors with demonstrated links to cortisol in pregnancy
Focus on between-person associations of stress with cortisol levels	Employ person-centered approaches or multilevel modeling to parse within- and between-person associations of stress and cortisol and account for individual differences