Stress & Fertility

Stress & Fertility

Overview

  • Presenters: Dr. Syd Miller, Stephane Jette, Cindy Lucio, Andrea Tkalec

  • Scope of the discussion on fertility, infertility, stress, its effects, physiological mechanisms, and empirical studies.

What is Fertility & Infertility?

  • Fertility:

    • Defined as the capacity to reproduce, which includes both getting pregnant and carrying a pregnancy to term.

  • Infertility:

    • Defined as attempting to conceive for 12 months without a pregnancy.

    • Includes the inability to carry a pregnancy to term.

Gonads

  • Definition: Sex glands that produce gametes, specifically gonads referred to as ovaries (female) and testes (male).

  • Hormonal Regulation of Production:

    • The hypothalamus releases gonadotropin-releasing hormone (GnRH).

    • GnRH travels to the anterior pituitary, stimulating the release of:

    • Luteinizing hormone (LH)

    • Follicle-stimulating hormone (FSH)

  • This production pathway is vital for reproductive function in both sexes.

HPG Axis (Hypothalamic-Pituitary-Gonadal Axis)

  • Key Components:

    • Gonadotropin-releasing hormone (GnRH) from the hypothalamus stimulates the anterior pituitary.

    • Anterior pituitary releases:

    • Luteinizing Hormone (LH)

    • Follicle-Stimulating Hormone (FSH)

  • Roles of LH and FSH:

    • LH is critical in:

    • Triggering ovulation in females through an LH surge.

    • Stimulating testosterone production in males, which is essential for spermatogenesis.

    • FSH is critical in:

    • Stimulating production and growth of germ cells.

    • Promoting pregnancy continuation in females and aiding spermatogenesis in males.

Effects of Stress on Reproductive Function

Stress and Reproductive Function in Male Rats

  • Impact of Acute and Chronic Stress:

    • Stress, particularly immobilization stress, leads to increased production of glucocorticoids, which subsequently inhibits downstream HPG activity, thereby reducing reproductive function (Kirby et al., 2009).

  • In a study:

    • 3 hours of immobilization stress for 14 days led to increased RFRP levels affecting HPG functioning.

  • Forced Swimming Stress Procedure:

    • Wistar rats were forced to swim for 3 minutes daily for 15 days.

    • Measurements included testicular weight and seminal vesicle weight.

    • Results indicated:

    • No effect on fertility despite reduced spermatid production.

    • Prolonged stress negatively affects spermatogenesis.

Prenatal Stress in Rats

  • Prenatal stress leads to:

    • Fewer conceptions, higher rates of spontaneous abortion, and lower viability in young.

    • Affects balance of adrenal and gonadal hormones during key developmental stages, causing adult reproductive dysfunction (Herrenkohl, 1979).

Environmental Psychosocial Factors in Stress and Fertility

  • Stress-related disorders in women:

    • Examples include chronic anovulation and hyperprolactinemia.

  • Stress-related disorders in men:

    • Affect sperm count, motility, and morphology leading to infertility.

Workplace Hazards

  • Comparison of infertile vs. fertile men using extensive questionnaires.

    • Infertile men show increased exposure to stressors (e.g., solvents) which negatively affects sperm metrics.

  • Identified a dose-response relationship where increased stress correlated with decreased sperm quality.

Stress and Conception

  • Research hypothesized less stress might correlate with conception months, contrasting with months without conception (Ed-Helaly et al., 2010).

  • 13 women were assessed over cycles with stress self-reports, hormonal assays indicating:

    • Self-reports showed correlations, but hormone assays did not provide significant statistical correlation due to methodological limitations (Boivin et al., 2006).

Age, Social Position, and Stress Impact on Fertility

  • Lower social positions correspond with higher stress effects on fertility, whilst higher positions do exert a significant stress impact.

  • Age influences, where older age appeared to reduce stress's negative impact on reproductive functions (Boivin et al., 2006).

Sperm Quality Related to Stress

  • A study on 744 fertile men revealed that major life stressors correlated with:

    • Decreased sperm concentration and motility.

    • Increased likelihood of below-normal sperm metrics as per WHO guidelines (Sanders & Bruce, 1997).

Emotional Stress and Sperm Health

  • Emotional stress leads to a significant reduction in the number of “healthy” sperm, showing a direct relationship between psychological state and reproductive health (Collodel et al., 2008).

Psychological Implications of Infertility

  • Infertility often portrayed as role failure, producing roles and identity stresses impacting psychological well-being and infertility perceptions (Greil et al., 1988).

  • Infertile women view their situation as more stressful compared to male partners, leading to compounded emotional responses potentially reducing fertility chances.

Risk Factors for Miscarriage

  • Elevated stress levels during pregnancy have been associated with higher miscarriage risks (80%), shown in comparative studies (Wisborg et al., 2008).

  • However, high stress alone isn’t a direct miscarriage risk; rather it’s the behavioral responses (e.g., substance use) under stress that can pose risks (Nelson et al., 2003).

Summary Points

  • Stress has significant correlations with hormonal changes negatively influencing reproductive health.

  • Environmental factors, including stressors from work and social pressures, contribute directly to reproductive difficulties.

  • Difficulty conceiving leads to increased stress, which can create a cyclical relationship fostering further fertility problems.

References

  • Compiled essential references from various studies regarding the impact of stress on fertility, emphasizing both psychological and physiological aspects of reproductive health.