Stress & Fertility: A Summary of Studies (February 19, 2024 PDF)

Monday, February 19, 2024 STRESS & FERTILITY What is Fertility? Fertility: capacity to reproduce (entails both getting pregnant and carrying to term) Infertility: 12 months trying with no pregnancy; inability to carry to term GONADS Gonads: A sex gland in which gametes are produced - gonad: ovary /...

Monday, February 19, 2024 STRESS & FERTILITY What is Fertility? Fertility: capacity to reproduce (entails both getting pregnant and carrying to term) Infertility: 12 months trying with no pregnancy; inability to carry to term GONADS Gonads: A sex gland in which gametes are produced - gonad: ovary / testis produce egg/sperm Production is regulated by various hormones - The hypothalamus releases a releasing hormone which travels to the anterior pituitary - In the anterior pituitary, LH and FSH are released - Gonads are released Biology HPG AXIS Hypothalamus (GRH) > Anterior Pituitary (LH/FSH) > Gonads (egg/sperm) LUTEINIZING HORMONE (LH) Creation of gonads (sperm/eggs) - Too high: premature menopause/ testicular failure - Too low: failure of gonadal function - Females: LH surge: acute rise of LH which triggers ovulation - Males: Production of testosterone and affects spermatogenesis FOLLICLE-STIMULATING HORMONE (FSH) Stimulates production of germ cells (environment) - Too high: premature menopause/ testicular failure - Too low: failure of gonadal function - Females: Growth and recruitment of ovum Promotes pregnancy continuation - Males: Stimulates maturation of seminiferous tubules and spermatogenesis 1 Monday, February 19, 2024 EFFECTS OF STRESS Triggers hypothalamus and anterior pituitary directly Directly acts on the release of LH/ FSH Study — Stress suppresses reproduction function in male rats Method: rats placed in acute vs chronic immobilization stress Results: ✓ High Glucocorticoids = cortisol levels = high RFRP expression in the dorsomedial hypothalamus (DMH) ✓ Increase in RFRP is associated with inhibition of downstream HPG activity ✓ Lower Reproductive function Study — Chronic stress condition Methods: Immobilized for 3 hrs / day for 14 days Results: ✓ Led to up-regulation of RFRP ✓ LH lowers the longer they are under stress ✓ Under chronic stress, cortisol increases = LH decreases Stress suppresses reproduction function in male rats 2 Monday, February 19, 2024 Study — Fertility of male adult rats subjected to stress (1) Procedure: rats forced to swim for 3 mins in water at 32°C daily for 15 days Tested for: testicular weight, seminal vesicle weight, ventral prostate weight Fertility assessment: control and stressed males were mated with sexually mature normal females Results: ✓ Stress caused by forced swimming did not affect fertility ✓ Significantly low spermatid production ✓ Prolonged stress effects spermatogenesis (seen after a cycle of sperm production) Study — Fertility of male adult rats subjected to stress (2) Procedure: immobilization on rats were 40 days old rats (pre-puberty), Immobilized for 6 hrs/ day for either 15 or 60 days ; 55-day-old were placed with receptive adult females to examine sexual behaviour; 100-day-old rats were mated with sexually mature females to assess fertility rates Results: ✓ Adult rats presented a significant low in fertility rates ✓ Enhances sexual performance at the onset of puberty ✓ Decrease fertility during adulthood in male rats PRENATAL STRESS (RATS) - Prenatal stress => Fewer conceptions, more spontaneous abortions and fewer viable young Offspring = low birth weight + less likely to survive the neonatal period - Influence the balance of adrenal and gonadal hormones during a critical stage of fetal hypothalamic differentiation Producing a variety of reproductive dysfunctions in adulthood Environmental Aspect (psychosocial) Stress Related Disorders in Women Chronic anovulation Decreased sperm count Hypothalamic amenorrhea Decreased sperm motility Pseudocyesis Altered sperm morphology Stress-related eating disorders Impotence Exercise and menstrual dysfunction Ejaculatory disorders Hyperprolactinemia Decreased serum LH and testosterone Early pregnancy failure 3 Stress Related Disorders in Men Monday, February 19, 2024 Study — Workplace Hazards Participants: Infertile Men (255) vs. Fertile Men (273) Results: ✓ Solvents & paintings materials, Stress, VDTs, Shift Work ✓ Stress effect in dose-response manner ✓ Sperm Motility and Morphological Index Infertile Months vs. Fertile Months (women) Research Question: Do women have less stress in the months they actually conceive? Hypothesis: Less Stress = Months with Conception / More stress = Months without Conception Results: ✓ On months where hormones were higher/lower = no difference in conceptions ✓ On months where women reported more stress/mood changes = more difficulty to conceive AGE & SOCIAL POSITION Summary: Sample: Already those with Fertility Problem (but considered reproductively able medically) Comparison: “Success” vs “Fail” to get pregnant 2 factors important to get pregnant: Age and Social Position = Moderators Age: Age up = Less effect of stress on fertility Social Position (SES): Lower Social Position = More effect of stress on fertility Higher Social Position = More effect of stress on Fertility Study — Sperm Quality and Stress Participants: Fertile Men (n = 744) Goal: Is sperm quality (motility and shape) affected by major stressful events? Results: the experience of 2+ life events was associated with: ✓ decreased sperm concentration, TC, and percent motile sperm (sperm significantly affected) ✓ increased likelihood of classification below WHO thresholds for ‘‘normal’’ for concentration, motility, and morphology Effects of stress on sperm quality - Emotional stress plays a detrimental role on fertility The ejaculate of 20 men was studied the number of “healthy” sperm was significantly reduced in participants who were depicted as being stressed ✓ The results show that the number of “healthy” sperm was significantly higher after the therapy 4 Monday, February 19, 2024 ✓ i.e. if stressed, sperm becomes less healthy; when receiving therapy, sperm becomes healthier Infertility causes stress which leads to more infertility Stress, gender & fertility - Women experiencing social pressure for motherhood view infertility as more stressful - Research has shown that working out of the home is beneficial to women - Women whose roles are limited pending motherhood, may experience infertility experience more distress than women engaged in multiple roles Inability to conceive: has been depicted as role failure and as socially stigmatizing - This produces stressors on the need to conceive - If a women cannot conceive a child she will become increasingly more stressed which will reduce her chances of conceiving - Infertile wives perceive their fertility problem as much more stressful than their husbands - Infertile wives felt themselves as being more responsible for the infertility Husbands also attributed the responsibility to their wives This feeling of inadequacy led the women to stress even more about getting pregnant which isn’t beneficial to fertility STRESS ÈFERTILITY PROBLEMS - Excessive emotional stress can cause chronic anovulation (no egg, no pregnancy) - Elevated cortisol levels are associated with amenorrhea DISTRESS & FERTILITY - Potential predictors of distress Gender role identity and infertility Career role salience and infertility Social pressure for motherhood and infertility Study — Predictors of distress in women being treated for infertility Participants: 119 women (from 23-49 yo) Results: ✓ 42% of the participants in this study experienced clinically significant levels of distress ✓ 62% were considered to be clinically symptomatic for stress disorders ✓ Participants tended to view infertility as very stressful Stress & Miscarriage - Stress may lead to miscarriage in pregnant women - Compared with women with an intermediate level of psychological stress during pregnancy, women with a high level of stress had 80% increased risk of stillbirth 5 Monday, February 19, 2024 DIFFERING OUTCOMES - Women reporting high stress did not have an higher risk of miscarriage when looking at stress alone - Women under stress were more likely to use drugs, which might be risk factors for miscarriage independently Summary - Stress influences the HPG axis leading to a decrease in gonad functioning - Environmental factors seem to play a role in stress related to reproductive difficulties - Difficulty conceiving or carrying to term, leads to stress about infertility which leads to increased future fertility problems 6