THE BIOLOGY OF STRESS
Historically it was believed that infertility, particularly "functional" infertility , was attributed to abnormal psychological functioning. It was not until the 1940's and 1950's that "psychogenic" infertility was considered as a major cause of failure to conceive in as many as 50% of the cases. However, psychological and emotional factors were still commonly believed to be the culprit as late as the 1960's
The psychological views of Freud were still in the forefront and Psychogenic infertility was attributed to suppressed unconscious beliefs about unresolved Oedipal conflict, ambivalence toward the mother, anxiety about sexual feelings. or conflicts of gender identity. Fortunately, medical science was moving forward on research in reproductive endocrinology as well as in psychology to de-emphasize psychopathology as the cause of infertility. Research today has found their is little basis for the previous beliefs. In fact, existing research in the advances of reproductive endocrinology unburdens couples of the additional guilt of thinking that it is their mental stress that may be responsible for their infertility. Research today demonstrates that STRESS in general plays a major role.
Stress can be likened to a stone rolling down a hill, it gains momentum and gathers more moss getting bigger and bigger. The inability to conceive can be likened to this, month after month of disappointment causes stress and only aggravates infertility, causing a vicious cycle.
THE SCIENCE BEHIND INFERTILITY AND STRESS
We have all heard in recent years how stress can effect our general health, but have you ever wondered how exactly it affects our reproductive health? It is likely that it plays a major role in cases of infertility.
It all has to do with the stress hormones that are released. Lifestyle factors in itself can aggravate infertility albeit stress directly interferes with the balanced release of hormones required for the production and release of a mature egg. Although the research on male infertility is much more limited, it is known that emotional stress can cause impotence and premature ejaculation, so one could assume that stress in the male could effect sperm production and mobility.
Stress is defined as any event that a person perceives as threatening, and to protect itself the body responds to stressors by producing a hormone called cortisol. Small amounts of cortisol can be a positive thing, for example, when test taking, it heightens our memory, it increases our reaction time when driving if we need to avoid an accident, and it can give us that quick burst of energy for survival. However, if the source of stress is constant and the levels of cortisol increases, it interferes with the function of the hypothalamus, the region of the brain that produces sex hormones.
MECHANISMS THROUGH WHICH STRESS REDUCES FERTILITY
The body has a natural automatic built in safety system. When it is threatened it immediately goes into survival mode and activates the sympathetic nervous system with the classic "fight or flight" response, which nature designed to allow for survival in challenging times . This process happens due to a mechanism which begins in the brain specifically the hypothalamus. The hypothalamus produces a hormone called corticotropin releasing factor (CRF) which activates the hypothalomus-pituitary-adrenal (HPA) system. These three glands work together through feedback mechanisms to perceive stressors. causing it to release neurotransmitters (chemical messengers) called catacolamines, as well as cortisol, the primary stress hormone. Adrenalin, the hormone released by the adrenal glands., though they helps us to escape from danger, and allow our bodies to successfully over come major stress and threats, they also inhibit our ability to utilize progesterone, a very important consideration for fertility.
Prolactin, a hormone which is released by the pituitary gland is usually released to stimulate lactation in preparation for nursing. (Most of us are aware that nursing mothers very rarely fall pregnant. ) However, under stress, the pituitary gland emits more prolactin in order to impair fertility. It is at this time the body is letting us know we should not be pregnant under stress.
Cortisol a major stress hormone has been shown to affect reproduction in multiple ways. It interferes with the surge of luteinizing hormone (LH) from the pituitary, delaying it and making the surge less powerful. LH is responsible for the final development of the follicle into the corpus luteum and the release of the egg. this has many negative impacts on healthy ovulation and on the hormones required to sustain implantation. Formation of a healthy corpus luteum is required to produce progesterone which allows for full development of the endometrial lining and hence, implantation.
High levels of glucocorticoid (stress hormone) are also known to reduce estrogen secretion by the follicle. Low estrogen levels will reduce fertile mucous and the development of the endometrial lining.
stress & infertility
Stress and stress hormones can cause infertility in the following ways:
Impairs follicle health and development by reducing the secretion of estrogen from the follicles which reduces the thickness of the endometrium and the fertile mucous.
Reduces the secretion of progesterone from the corpus luteum in the luteal phase, and thus affects implantation.
Increases prolactin secretion by the pituitary gland, which inhibits ovarian function.
Affects the surge of luteinizing hormone (LH) from the pituitary gland which is responsible for stimulating ovarian function. * Affects the part of the immune system responsibility for preventing miscarriage in early part of pregnancy.