|
Infertility primarily refers to the biological inability of a man or a woman to contribute to conception. Infertility may also refer to the state of a woman who is unable to carry a pregnancy to full term. There are many biological causes of infertility, some which may be bypassed with medical intervention. Women who are fertile experience a natural period of fertility before and during ovulation, and they are naturally infertile during the rest of the menstrual cycle. Fertility awareness methods are used to discern when these changes occur; by tracking changes in cervical mucus or basal body temperature. Definition There are strict definitions of infertility used by many doctors. However, there are also similar terms, e.g. subfertility for a more benign condition and fecundity for the natural improbability to conceive.
Infertility Reproductive endocrinologists, the doctors specializing in infertility, consider a couple to be infertile if: - the couple has not conceived after 12 months of contraceptive-free intercourse if the female is under the age of 34
- the couple has not conceived after 6 months of contraceptive-free intercourse if the female is over the age of 35 (declining egg quality of females over the age of 35 account for the age-based discrepancy as when to seek medical intervention)
- the female is incapable of carrying a pregnancy to term.
Fecundity Healthy couples in their mid-20s having regular sex have a one-in-four chance of getting pregnant in any given month. This is called "Fecundity".
Subfertility A couple that has tried unsuccessfully to have a child for a year or more is said to be subfertile. The couple's fecundability rate is approximately 3-5%. Many of its causes are the same as those of infertility. Such causes could be endometriosis, or polycystic ovarian syndrome.
Prevalence Infertility affects approximately 10% of people of reproductive age, and 15% of couples. Roughly 40% of cases involve a male contribution or factor, 40% involve a female factor, and the remainder involve both sexes.
In the U.S. According to the American Society for Reproductive Medicine, infertility affects about 6.1 million people in the U.S., equivalent to ten percent of the reproductive age population. Female infertility accounts for one third of infertility cases, male infertility for another third, combined male and female infertility for another 15%, and the remainder of cases are "unexplained".
Causes This section deals with unintentional causes of sterility. For more information about surgical techniques for preventing procreation, see sterilization.
Primary vs. secondary Couples with primary infertility have never been able to conceive , while, on the other hand, secondary infertility is difficulty conceiving after already having conceived and carried a normal pregnancy. Technically, secondary infertility is not present if there has been a change of partners. Some women are infertile because their ovaries do not mature and release eggs. In this case synthetic FSH by injection or Clomid (Clomiphene citrate) via a pill can be given to stimulate follicles to mature in the ovaries.
Causes in either sex Factors that can cause male as well as female infertility are: - Genetic
- General factors
- Hypothalamic-pituitary factors:
Female infertility Factors relating only to female infertility are: - General factors
- Hypothalamic-pituitary factors:
- Ovarian factors
- Tubal/peritoneal factors
- Uterine factors
- Cervical factors
- Vaginal factors
- Genetic factors
Male infertility Factors relating only to male infertility include: - Pretesticular causes
- Hypogonadism due to various causes
- Drugs, alcohol, smoking
- Strenuous riding [Bicycle, Horseback]
- Testicular factors
- Posttesticular causes
Combined infertility In some cases, both the man and woman may be infertile or sub-fertile, and the couple's infertility arises from the combination of these conditions. In other cases, the cause is suspected to be immunological or genetic; it may be that each partner is independently fertile but the couple cannot conceive together without assistance.
Unexplained infertility In about 15% of cases the infertility investigation will show no abnormalities. In these cases abnormalities are likely to be present but not detected by current methods. Possible problems could be that the egg is not released at the optimum time for fertilization, that it may not enter the fallopian tube, sperm may not be able to reach the egg, fertilization may fail to occur, transport of the zygote may be disturbed, or implantation fails. It is increasingly recognized that egg quality is of critical importance and women of advanced maternal age have eggs of reduced capacity for normal and successful fertilization.
Diagnosis
Male infertility The diagnosis of infertility begins with a medical history and physical exam by a urologist, preferably one with experience or who specializes in male infertility. The provider may order blood tests to look for hormone imbalances or disease. A semen sample will be needed. Blood tests may indicate genetic causes.
Efficiency In the majority of cases of male infertility and low sperm quality, no clear cause can be identified with current diagnostic methods.
Medical history The cornerstone of the male partner evaluation is the history. It should note the duration of infertility, earlier pregnancies with present or past partners, and whether there was previous difficulty with conception. The history should include prior testicular (penis) insults (torsion, cryptorchidism, trauma), infections (mumps orchitis, epididymitis), environmental factors (excessive heat, radiation, chemotherapy), medications (anabolic steroids, cimetidine, and spironolactone may affect spermatogenesis; phenytoin may lower FSH; sulfasalazine and nitrofurantoin affect sperm motility), and drug use (alcohol, smoking, marijuana). Sexual habits, frequency and timing of intercourse, use of lubricants, and each partner's previous fertility experiences are important. Loss of libido and headaches or visual disturbances may indicate a pituitary tumor. The past medical or surgical history may reveal thyroid or liver disease (abnormalities of spermatogenesis), diabetic neuropathy (retrograde ejaculation), radical pelvic or retroperitoneal surgery (absent seminal emission secondary to sympathetic nerve injury), or hernia repair (damage to the vas deferens or testicular blood supply).
Physical examination A complete examination of the infertile male is important to identify general health issues associated with infertility. For example, the patient should be adequately virilized; signs of decreased body hair or gynecomastia may suggest androgen deficiency. The scrotal contents should be carefully palpated with the patient standing. As it is often psychologically uncomfortable for men to be examined, one helpful hint is to make the examination as efficient and as matter of fact as possible. The peritesticular area should also be examined. Irregularities of the epididymis, located posterior-lateral to the testis, include induration, tenderness, or cysts.
Sperm sample - Main article: semen quality
The volume of the semen is measured, as well as the number of sperm in the sample. How well the sperm move is also assessed. This is the most common type of fertility testing.
Blood sample A blood sample can reveal genetic causes of infertility, e.g. a Y chromosome microdeletion, cystic fibrosis.
Female infertility Diagnosis of infertility begins with a medical history and physical exam. The healthcare provider may order tests, including the following: - an endometrial biopsy, to verify ovulation and inspect the lining of the uterus
- hormone testing, to measure levels of female hormones at certain times during a menstrual cycle
- day 2 or 3 measure of fsh and estrogen, to assess ovarian reserve
- measurements of thyroid function (a thyroid stimulating hormone(TSH) level of between 1 and 2 is considered optimal for conception)
- laparoscopy, which allows the provider to inspect the pelvic organs
- measurement of progesterone in the second half of the cycle to help confirm ovulation
- Pap smear, to check for signs of infection
- pelvic exam, to look for abnormalities or infection
- a postcoital test, which is done soon after intercourse to check for problems with sperm surviving in cervical mucous (not commonly used now because of test unreliability)
- special X-ray tests
Diagnosis and treatment of infertility should be made by physicians who are fellowship trained as reproductive endocrinologists. Reproductive Endocrinologists are usually Obstetrician-Gynecologists with advanced training in Reproductive Endocrinology & Infertility (in North America). These highly educated professionals and qualified physicians treat Reproductive Disorders affecting not only women but also men, children, and teens. Prospective patients should note that reproductive endocrinology & infertility medical practices do not see women for general maternity care. The practice is primarily focused on helping their patients to conceive and to correct any issues related to recurring pregnancy loss.
Treatment - Main article: Assisted reproductive technology
Treatment of infertility usually starts with medication. In vitro fertilization (IVF) in addition to various forms and developments of it (ICSI, ZIFT, GIFT) is another solution. They all include that the fertilization takes place outside the body. On the other hand, an insemination can make a fertilization inside the body. Other techniques are e.g. tuboplasty, assisted hatching and PGD.
Prevention
Male infertility Some cases of male infertility may be avoided by doing the following: - Avoid smoking as it damages sperm DNA
- Avoid drugs and medications known to cause fertility problems, like steroids and some antifungal medications.
- Avoid excessive exercise.
- Avoid exposure to environmental hazards such as pesticides and heavy metals such as lead, mecury and cadmium.
- Avoid frequent hot baths or use of hot tubs.
- Avoid tight underwear or pants.
- Eat a diet with adequate folic acid, vitamin C, Zinc, calcium, magnesium, selenium, iron loaded food.
- Get early treatment for sexually transmitted diseases.
- Have regular physical examinations to detect early signs of infections or abnormalities.
- Keep diseases, such as diabetes and hypothyroidism, under control.
- Practice safer sex to avoid sexually transmitted diseases.
- Take a lycopene supplement.
- Wear protection over the scrotum during athletic activities.
Female infertility Some cases of female infertility may be prevented by taking the following steps: - Avoid excessive exercise.
- Avoid smoking.
- Control diseases such as diabetes and hypothyroidism
- Eat a well balanced nutritious diet with plenty of fresh fruits and vegetables (plenty of folates).
- Follow good weight management guidelines.
- Practice safer sex to avoid sexually transmitted diseases.
- Get early treatment for sexually transmitted diseases.
- Have regular physical examinations (including pap smears) to detect early signs of infections or abnormalities.
- Limit caffeine and alcohol intake.
- Ask your mother (biological) to share any unusual or abnormal issues she had related to conceiving. For example, premature menopause in your mother can be genetic and passed on to you, which limits the years in which you will have optimal egg quality.
- Fertility starts declining after age 27 and drops at a somewhat greater rate after age 35 It should be noted, however, that fertility does not ultimately cease before menopause.
Ethics There are several ethical issues associated with infertility and its treatment. - High-cost treatments are out of financial reach for some couples.
- Debate over whether health insurance companies should be forced to cover infertility treatment.
- Allocation of medical resources that could be used elsewhere
- The legal status of embryos fertilized in vitro and not transferred in vivo.
- Anti-abortion opposition to the destruction of embryos not transferred in vivo.
- IVF and other fertility treatments have resulted in an increase in multiple births, provoking ethical analysis because of the link between multiple pregnancies, premature birth, and a host of health problems.
- Religious leaders' opinions on fertility treatments.
- Infertility caused by DNA defects on the Y chromosome is passed on from father to son. If natural selection is the primary error correction mechanism that prevents random mutations on the Y chromosome, then fertility treatments for men with abnormal sperm (in particular ICSI) only defer the underlying problem to the next male generation.
Psychological impact Infertility may have profound psychological effects. Partners may become more anxious to conceive, ironically increasing sexual dysfunction. Marital discord often develops in infertile couples, especially when they are under pressure to make medical decisions. Women trying to conceive often have clinical depression rates similar to women who have heart disease or cancer. Even couples undertaking IVF face considerable stress, especially the female partner. For those who don't desire to have children, infertility may have a positive psychological impact, particularly in areas where emergency contraception and abortion services are difficult to obtain.
Social impact In many cultures, inability to conceive bears a stigma. In closed social groups, a degree of rejection (or a sense of being rejected by the couple) may cause considerable anxiety and disappointment. Some respond by actively avoiding the issue altogether; middle-class men are the most likely to respond in this way . Groups like INCIID provide social support and disseminate information to lessen the burden. There are legal ramifications as well. Infertility has begun to gain more exposure to legal domains. An estimated 4 million workers in the U.S. used the Family and Medical Leave Act (FMLA) in 2004 to care for a child, parent or spouse, or because of their own personal illness. Many treatments for infertility, including diagnostic tests, surgery and therapy for depression, can qualify one for FMLA leave.
See also Infertility in science fiction
Category: Bio-medical
Type: Glossaries and Dictionaries
|
