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Updated: May 19, 2026

Using a Murine Model of Psychosocial Stress in Pregnancy as a Translationally Relevant Paradigm for Psychiatric Disorders in Mothers and Infants
Published on: June 13, 2021
Preconception stress and the secondary sex ratio: a prospective cohort study
Rebecca J Chason1, Alexander C McLain, Rajeshwari Sundaram
1Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA. rebecca.chason@nih.gov
Objective:
To study the association between salivary stress biomarkers and the secondary sex ratio.
Design:
Prospective, longitudinal cohort study.
Setting:
Community setting in the United Kingdom.
Patient(S):
On discontinuation of contraception for purposes of becoming pregnant, 338 women aged 18-40 years with complete data (90%) were followed until pregnant or up to six menstrual cycles.
Intervention(S):
None.
Main Outcome Measure(S):
Secondary sex ratio.
Result(S):
Human chorionic gonadotropin pregnancies were detected in 207 (61%) women of whom 130 (63%) delivered singleton infants with available gender data. The adjusted odds ratio for a male birth was decreased for women in the highest quartile (AOR = 0.26; 95% confidence interval = 0.09, 0.74) of salivary cortisol relative to women in the lowest quartile during cycle 1. An inverse relation was observed between α-amylase and the 2° sex ratio, though not statistically significant.
Conclusion(S):
Our findings are consistent with a reversal in the 2° sex ratio with increasing preconception salivary cortisol concentrations. This relation suggests that activation of the hypothalamus-pituitary-adrenal axis may have implications in sex allocation and requires further study.
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