While this study did not involve IVF patients, its conclusions nevertheless have relevance to women trying to fall pregnant with IVF. The study showed a clear relationship with higher stress levels and reduced conception rates. This may be one of the ways that acupuncture, which reduces stress hormones, can improve fertility.
OBJECTIVE: To assess salivary stress biomarkers (cortisol and alpha-amylase) and female fecundity.
DESIGN: Prospective cohort design.
SETTING: United Kingdom.
PATIENT(S): 274 women aged 18-40 years who were attempting pregnancy.
INTERVENTION(S): Observation for six cycles or until pregnancy: women collected basal saliva samples on day 6 of each cycle, and used fertility monitors to identify ovulation and pregnancy test kits for pregnancy detection.
MAIN OUTCOME MEASURE(S): Salivary cortisol (mug/dL) and alpha-amylase (U/mL) concentration measurements; fecundity measured by time-to-pregnancy and the probability of pregnancy during the fertile window as estimated from discrete-time survival and Bayesian modeling techniques, respectively.
RESULT(S): Alpha-amylase but not cortisol concentrations were negatively associated with fecundity in the first cycle (fecundity odds ratio = 0.85; 95% confidence interval 0.67, 1.09) after adjusting for the couples' ages, intercourse frequency, and alcohol consumption. Statistically significant reductions in the probability of conception across the fertile window during the first cycle attempting pregnancy were observed for women whose salivary concentrations of alpha-amylase were in the upper quartiles in comparison with women in the lower quartiles (highest posterior density: -0.284; 95% interval -0.540, -0.029).
CONCLUSION(S): Stress significantly reduced the probability of conception each day during the fertile window, possibly exerting its effect through the sympathetic medullar pathway.