Premature ovarian failure
Premature ovarian failure is the loss of function of the ovaries before age 40. A commonly cited triad for the diagnosis is amenorrhea, hypergonadotropism, and hypoestrogenism. If it has a genetic cause, it may be called gonadal dysgenesis.
The term "primary ovarian insufficiency" was first used in 1942 by Fuller Albright who first described the condition. About 5 to 10% of women with primary ovarian insufficiency conceive subsequent to the diagnosis without medical intervention.
Signs and symptoms
On average, the ovaries supply a woman with eggs until age 51, the average age of natural menopause.POF is not the same as a natural menopause, in that the dysfunction of the ovaries, loss of eggs, or removal of the ovaries at a young age is not a normal physiological occurrence.
Infertility is the result of this condition, and is the most discussed problem resulting from it, but there are additional health implications of the problem, and studies are ongoing. For example, osteoporosis affects almost all women with POF due to an insufficiency of estrogen. There is also an increased risk of heart disease, hypothyroidism in the form of Hashimoto's thyroiditis, Addison's disease, and other autoimmune disorders.
Hormonally, POF is defined by abnormally low levels of estrogen and high levels of FSH, which demonstrate that the ovaries are no longer responding to circulating FSH by producing estrogen and developing fertile eggs. The ovaries will likely appear shriveled.
The age of onset can be as early as 11 years, or can even exist from birth, but varies widely. If a girl never begins menstruation, it is called primary ovarian failure. The age of 40 was chosen as the cut-off point for a diagnosis of POF. This age was chosen somewhat arbitrarily, as all women's ovaries decline in function over time. However an age needed to be chosen to distinguish usual menopause from the abnormal state of premature menopause. Premature ovarian failure has components to it that distinguish it from normal menopause.
By the age of 40, approximately one percent of women have POF. Women with POF usually experience menopausal symptoms that are more severe than the symptoms found in older menopausal women.
Emotional health
The most common words women use to describe how they felt in the 2 hours after being given the diagnosis of primary ovarian insufficiency are "devastated, "shocked," and "confused." These are words that describe emotional trauma. The diagnosis is more than infertility and affects a woman’s physical and emotional well-being. Patients face the acute shock of the diagnosis, associated stigma of infertility, grief from the death of dreams, anxiety and depression from the disruption of life plans, confusion around the cause, symptoms of estrogen deficiency, worry over the associated potential medical sequelae such as reduced bone density and cardiovascular risk, and the uncertain future that all of these factors create. There is a need for an evidence-based integrative medicine program to assist women with primary ovarian insufficiency. Presently such a program does not exist in the community, but a community of practice has formed to address this deficiency. Women with primary ovarian insufficiency perceive lower social support than control women, so building a trusted community of practice for them would be expected to improve their well being. It is important to connect women with primary ovarian insufficiency to an appropriate collaborative care team because the condition has been clearly associated with suicide related to the stigma of infertility. Suicide rates are known to be increased in women who experience infertility.Causes
The cause of POF is usually idiopathic. Some cases of POF are attributed to autoimmune disorders, others to genetic disorders such as Turner syndrome and Fragile X syndrome. An Indian study showed a strong correlation between incidence of POF and certain variants in the inhibin alpha gene. In many cases, the cause cannot be determined. Chemotherapy and radiation treatments for cancer can sometimes cause ovarian failure. In natural menopause, the ovaries usually continue to produce low levels of hormones, but in chemotherapy or radiation-induced POF, the ovaries will often cease all functioning and hormone levels will be similar to those of a woman whose ovaries have been removed. Women who have had a hysterectomy tend to go through menopause several years earlier than average, likely due to decreased blood flow to the ovaries. Family history and ovarian or other pelvic surgery earlier in life are also implicated as risk factors for POF.There are two basic kinds of premature ovarian failure. Case 1) where there are few to no remaining follicles and case 2) where there are an abundant number of follicles. In the first situation the causes include genetic disorders, autoimmune damage, chemotherapy, radiation to the pelvic region, surgery, endometriosis and infection. In most cases the cause is unknown. In the second case one frequent cause is autoimmune ovarian disease which damages maturing follicles, but leaves the primordial follicles intact. Also, in some women FSH may bind to the FSH receptor site, but be inactive. By lowering the endogenous FSH levels with ethinylestradiol or with a GnRH-a the receptor sites are free and treatment with exogenous recombinant FSH activates the receptors and normal follicle growth and ovulation can occur.
Genetic associations include:
- Genetic disorders
- Autoimmune diseases
- Tuberculosis of the genital tract
- Smoking
- Radiation and/or chemotherapy
- Ovarian failure following hysterectomy
- Prolonged GnRH therapy
- Enzyme defects
- Resistant ovary
- Induction of multiple ovulation in infertility
DNA repair deficiency
protein plays an essential role in the repair of DNA double-strand breaks by homologous recombination. Women with a germline BRCA1 mutation tend to have premature menopause as evidenced by the final menorrhea appearing at a younger age. BRCA1 mutations are associated with occult primary ovarian insufficiency. Impairment of the repair of DNA double-strand breaks due to a BRCA1 defect leads to premature ovarian aging in both mice and humans.In addition to BRCA1, the MCM8-MCM9 protein complex also plays a crucial role in the recombinational repair of DNA double-strand breaks. In humans, an MCM8 mutation can give rise to premature ovarian failure, as well as chromosomal instability. MCM9, as well as MCM8, mutations are also associated with ovarian failure and chromosomal instability. The MCM8-MCM9 complex is likely required for the homologous recombinational repair of DNA double-strand breaks that are present during the pachytene stage of meiosis I. In women homozygous for MCM8 or MCM9 mutations, failure to repair breaks apparently leads to oocyte death and small or absent ovaries.
Diagnosis
Serum follicle-stimulating hormone measurement alone can be used to diagnose the disease. Two FSH measurements with one-month interval have been a common practice. The anterior pituitary secretes FSH and LH at high levels due to the dysfunction of the ovaries and consequent low estrogen levels. Typical FSH in POF patients is over 40 mlU/ml.Treatment
Fertility
Between 5 and 10 percent of women with POF may become pregnant. Currently no fertility treatment has officially been found to effectively increase fertility in women with POF, and the use of donor eggs with in-vitro fertilization and adoption are popular as a means of achieving parenthood for women with POF. Some women with POF choose to live child-free.Currently New York fertility researchers are investigating the use of a mild hormone called dehydroepiandrosterone in women with POF to increase spontaneous pregnancy rates. Published results from studies conducted on DHEA have indicated that DHEA may increase spontaneously conceived pregnancies, decrease spontaneous miscarriage rates and improve IVF success rates in women with POF.
Additionally, over the last five years a Greek research team has successfully implemented the use of dehydroepiandrosterone for the fertility treatment of women suffering with POF.The majority of the patients were referred for donor eggs or surrogacy, however after a few months of DHEA administration, some succeeded in getting pregnant through IVF, IUI, IUTPI or natural conception. Many babies have been born after treatment with DHEA.
Ovarian tissue cryopreservation can be performed on prepubertal girls at risk for premature ovarian failure, and this procedure is as feasible and safe as comparable operative procedures in children.
In 2013, Kawamura in Japan and his collaborators at Stanford University published a paper showing a new way to treat infertility of POI patients by fragmenting ovaries followed by in vitro treatment of ovarian fragments with Akt stimulators and autografting. They successfully promoted follicle growth, retrieved mature oocytes, and performed in vitro fertilization. Following embryo transfer, a healthy baby was delivered. This IVA approach has been successfully adopted by a group in Zhengzhou University, China with two cases. Up to summer of 2018, there were more than one dozen successful cases in Japan, China, Spain, Poland, and Denmark.
Hormonal replacement
Most people develop symptoms of estrogen deficiency, including vasomotor flushes and vaginal dryness, both of which respond to hormone replacement therapy. There are several contraindications of estrogen supplement, including smokers over 35 years of age, uncontrolled hypertension, uncontrolled diabetes mellitus, or history of thromboemboli events.Women younger than 40 year with primary ovarian insufficiency benefit from physiologic replacement of hormones. Most authorities recommend that this hormone replacement continue until age 50 years, the normal age of menopause. The leading hormone replacement regimen recommended involves the administration of estradiol daily by either skin patch or vaginal ring. This approach reduces the risk of pulmonary embolism and deep venous thrombosis by avoiding the first pass effect on the liver that is induced by oral estrogen therapy. To avoid the development of endometrial cancer young women taking estradiol replacement need also to take a progestin in a regular cyclic fashion. The most evidence supports the use of medroxyprogesterone acetate per day for days one through 12 of each calendar month. This will induce regular and predictable menstrual cycles. It is important that women taking this regimen keep a menstrual calendar. If the next expected menses is late it is important to get a pregnancy test. It this is positive, the woman should stop taking the hormone replacement. Approximately 5 to 10% of women with confirmed primary ovarian insufficiency conceive a pregnancy after the diagnosis without medical intervention.
The transdermal estradiol patch is commonly recommended due to several advantages. It provides the replacement by steady infusion rather than by bolus when taking daily pills. It also avoids the first-pass effect in the liver.