The ovarian causes for an ovulatory dysfunction include:
Females are born with all of their eggs and they will use these eggs throughout their reproductive lifespan. At menopause, few to no remaining maturable eggs are thought to exist in the ovaries.
The decrease in fertility that is associated with maternal age is gradual rather than sudden and is usually thought to occur slowly after about the age of 30, then more rapidly after about 35 and much more rapidly after about 40 years of age.
The basis for the age related decline in fertility is not well characterized. It is widely believed that the best (most fertile) eggs undergo recruitment and maturation in the earlier portion of the reproductive lifespan and that those “left” in later years represent less ovulation and fertilization capable eggs.
A woman’s fertility may be directly related to the number of follicles (ovarian cysts containing maturable eggs) in her ovaries (that is, the “ovarian reserve”). The ovarian reserve is continually decreasing with maternal age due to the loss of many follicles each month.
There is also an age dependent increase in miscarriage. The reason for this is believed to be due to a greater number of errors in the final assortment of the egg’s chromosomes just prior to ovulation or at fertilization. These errors lead to an increased number of lethal chromosomal mutations in embryos. On the one hand it is unfortunate that there are so many chromosomal accidents and on the other hand it is fortunate that humans will quickly reject (abort) almost any chromosomal abnormality. The 0.6% rate of chromosomal anomalies in human liveborns is quite low compared to other animal species.
Surgery involving partial or complete removal of an ovary will result in fewer remaining eggs. Reports suggest that as little as one tenth of one ovary may be sufficient for fertility in the presence of an otherwise completely normal reproductive system. Certainly all other things being equal, the more eggs present in the ovary the greater the fertility.
Alkylating agents and/or higher cumulative dosages of any chemotherapy can destroy developing ovarian follicles. This may result in months to years of anovulation and amenorrhea. Generally, if the ovary does recover from the radiation or chemotherapy at a later date, the quality of the eggs that are matured is not compromised and therefore may result in normal pregnancies. There are no tests currently available to check remaining eggs for “any genetic problem” following these treatments.
When ovarian failure with amenorrhea occurs prior to 40 y/o this is called “premature ovarian failure” (POF). POF occurs in about 1 in 100 women. In the USA, a normal reproductive lifespan generally is from 14 to 44 y/o, and menopause occurs typically at about 52 y/o.
POF may be caused by a genetic abnormality. A normal duration reproductive life requires the presence of 2 fully functioning X chromosomes. If one X chromosome is completely lacking (resulting in “Turner’s syndrome”) then all the eggs that are present (in normal amount) during the female’s development within her mother’s uterus will have degenerated by the time of her birth. When a less severe abnormality exists on one of the X chromosomes, the only identified problem with the female may be POF due to the rapid depletion of her eggs. There are genetic tests (probes) available for some of these X chromosome abnormalities. Specific X testing may be useful for women with otherwise unexplained POF, especially if she has a female relative who might also carry the abnormality (who could then to use the information for her own family planning).
POF may be due to an immunologic abnormality. Autoimmune disease occurs when a woman’s immune system attacks her own organs. If this attack is directed against the ovary, ovarian failure is thought to be possible. I do not recommend these tests since anti-ovarian antibody testing can be expensive and it has been shown that up to 30% of normally ovulating women have the antiovarian antibodies.
Uncommon forms of POF exist. The “resistant ovary syndrome” (where numerous early stage follicles can be found but do not respond to FSH) and some “steroid hormone enzyme deficiencies” (where the enzymes required for hormone production are decreased or absent) possibly present as amenorrhea after a few spontaneous menses at puberty.
Cigarettes are associated with fertility problems. Research consistently demonstrates a significant decrease in fertility (up to 30-50%) when comparing smokers to nonsmokers.
Cigarette smoking may interfere with the communication between the brain and the ovary such that a smaller sized follicle develops. Cigarettes can limit the secretion of pituitary LH during the LH surge which might interfere with ovulation. Cigarettes can also directly reduce the number of eggs remaining in the ovary, with more than 13 studies showing that smokers go through menopause (ovarian failure due to egg depletion) 1-2 years prior to nonsmokers.
Cigarettes can result in tubal function abnormalities. Reports demonstrate that smokers have a 2-4 fold increase in ectopic pregnancy rate.
Cigarettes may result in implantation abnormalities. Reports demonstrate that smokers have up to 2 times as many miscarriages.
Cigarettes also result in male factor fertility abnormalities. Reports demonstrate decreases in semen analysis parameters in smokers.
When infection involves the reproductive organs the damage to those tissues can be extensive. If the ovary is involved, especially when there is an abscess involving the ovaries and tubes, the infection and inflammation can destroy the ovary to the point where a surgeon cannot even establish the presence of normal ovarian tissue. The woman can experience amenorrhea either immediately or within a year or so of treatment.
An abundant blood supply is required for the survival of the ovary, and if compromised either following surgery (uncommon) or due to blood clots developing in the vessels to the ovary (rare) deterioration of ovarian function may occur.
Endometriosis is associated with infertility but the mechanism is not clear. It is widely accepted that it is more difficult to stimulate ovulation with fertility medications in women with endometriosis.
Nonsteroidal anti-inflammatory drugs (NSAIDs) can inhibit ovulation. The physical release of the egg from the ovary seems to be partly dependent upon a class of molecules called prostaglandins. Medication that inhibits the production or function of prostaglandins (such as NSAIDs like Motrin or Alleve) may interfere with ovulation. NSAIDs have been shown to disrupt ovulation in rabbits and rodents.
Available Case Reports: