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|Classification and external resources|
|Classification and external resources|
Infertility is fundamentally the inability to conceive a baby. Infertility also refers to the state of a woman who is unable to carry a pregnancy to full term. There are many biological causes of infertility, including some that medical intervention can treat. Infertility has increased by 4 percent since the 1980s, mostly from problems with fecundity due to an increase in age. About 40 percent of the issues involved with infertility are due to the man, another 40 percent due to the woman, and 20 percent result from complications with both partners.
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.
Definitions of infertility differ. Demographers tend to define infertility as childlessness in a population of women of reproductive age, whereas the epidemiological definition refers to "trying for" or "time to" a pregnancy, generally in a population of women exposed to a probability of conception. The time needed to pass (during which the couple tries to conceive) for that couple to be diagnosed with infertility differs between different jurisdictions. Existing definitions of infertility lack uniformity, rendering comparisons in prevalence between countries or over time problematic. Therefore, data estimating the prevalence of infertility cited by various sources differs significantly. A couple that tries unsuccessfully to have a child after a certain period of time (often a short period, but definitions vary) is sometimes said to be subfertile, meaning less fertile than a typical couple. Both infertility and subfertility are defined as the inability to conceive after a certain period of time (the length of which vary), so often the two terms overlap.
The World Health Organization defines infertility as follows:
|“||Infertility is the inability to conceive a child. A couple may be considered infertile if, after two years of regular sexual intercourse, without contraception, the woman has not become pregnant (and there is no other reason, such as breastfeeding or postpartum amenorrhoea). Primary infertility is infertility in a couple who have never had a child. Secondary infertility is failure to conceive following a previous pregnancy. Infertility may be caused by infection in the man or woman, but often there is no obvious underlying cause.||”|
One definition of infertility that is frequently used in the United States by reproductive endocrinologists, doctors who specialize in infertility, to consider a couple eligible for treatment is:
These time intervals would seem to be reversed; this is an area where public policy trumps science. The idea is that for women beyond age 35, every month counts and if made to wait another 6 months to prove the necessity of medical intervention, the problem could become worse. The corollary to this is that, by definition, failure to conceive in women under 35 isn't regarded with the same urgency as it is in those over 35.
In the UK, the NICE guidelines define infertility as failure to conceive after regular unprotected sexual intercourse for 2 years in the absence of known reproductive pathology.
Researchers commonly base demographic studies on infertility prevalence on a five-year period. Practical measurement problems, however, exist for any definition, because it is difficult to measure continuous exposure to the risk of pregnancy over a period of years.
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 either carried the pregnancy to term or had a miscarriage). Secondary infertility is not present if there has been a change of partners (this follows tautologically from the convention of speaking of couples, rather than individuals, as being infertile; if there is a change of partners, then a new couple is created, with its own chances to be infertile.)
Prevalence of infertility varies depending on the definition, i.e. on the time span involved in the failure to conceive.
This section deals with unintentional causes of sterility. For more information about surgical techniques for preventing procreation, see Sterilization (surgical procedure).
Factors that can cause male as well as female infertility are:
German scientists have reported that a virus called Adeno-associated virus might have a role in male infertility, though it is otherwise not harmful. Mutation that alters human DNA adversely can cause infertility, the human body thus preventing the tainted DNA from being passed on.
The following causes of infertility may only be found in females. For a woman to conceive, certain things have to happen: intercourse must take place around the time when an egg is released from her ovary; the systems that produce eggs and sperm have to be working at optimum levels; and her hormones must be balanced.
For women, problems with fertilisation arise mainly from either structural problems in the Fallopian tube or uterus or problems releasing eggs. Infertility may be caused by blockage of the Fallopian tube due to malformations, infections such as chlamydia and/or scar tissue. For example, endometriosis can cause infertility with the growth of endometrial tissue in the Fallopian tubes and/or around the ovaries. Endometriosis is usually more common in women in their mid-twenties and older, especially when postponed childbirth has taken place.
Another major cause of infertility in women may be the inability to ovulate. Malformation of the eggs themselves may complicate conception. For example, polycystic ovarian syndrome is when the eggs only partially developed within the ovary and there is an excess of male hormones. 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.
Other factors that can affect a woman's chances of conceiving include being overweight or underweight, or her age as female fertility declines after the age of 35.
Sometimes it can be a combination of factors, and sometimes a clear cause is never established.
Common causes of infertility of females include:
The main cause of male infertility is low semen quality. In men who have the necessary reproductive organs to procreate, infertility can be caused by low sperm count due to endocrine problems, drugs, radiation, or infection. There may be testicular malformations, hormone imbalance, or blockage of the man's duct system. Although many of these can be treated through surgery or hormonal substitutions, some may be more indefinite. Infertility associated with viable, but immotile sperm may be caused by primary ciliary dyskinesia.
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.
In the US, up to 20% of infertile couples have unexplained infertility. 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. Also, polymorphisms in folate pathway genes could be one reason for fertility complications in some women with unexplained infertility.
If both partners are young and healthy and have been trying to conceive for one year without success, a visit to a physician or women's health nurse practitioner (WHNP) could help to highlight potential medical problems earlier rather than later. The doctor or WHNP may also be able to suggest lifestyle changes to increase the chances of conceiving.
Women over the age of 35 should see their physician or WHNP after six months as fertility tests can take some time to complete, and age may affect the treatment options that are open in that case.
A physiiann or WHNP takes a medical history and gives a physical examination. They can also carry out some basic tests on both partners to see if there is an identifiable reason for not having achieved a pregnancy. If necessary, they refer patients to a fertility clinic or local hospital for more specialized tests. The results of these tests help determine the best fertility treatment.
Treatment depends on the cause of infertility, but may include counselling, fertility treatments, which include in vitro fertilization. According to ESHRE recommendations, couples with an estimated live birth rate of 40% or higher per year are encouraged to continue aiming for a spontaneous pregnancy. Treatment methods for infertility may be grouped as medical or complementary and alternative treatments. Some methods may be used in concert with other methods. Drugs used for women include Clomiphene citrate, Human menopausal gonadotropin, Follicle-stimulating hormone, Human chorionic gonadotropin, Gonadotropin-releasing hormone analogs, Aromatase inhibitor, Metformin.
In 2007 the FDA cleared the first at home tier one medical conception device to aid in conception. The key to the kit are cervical caps for conception. This at home [cervical cap] insemination method allows all the semen to be placed up against the cervical os for six hours allowing all available sperm to be placed directly on the cervical os. For low sperm count, low sperm motility, or a tilted cervix using a cervical cap aids conception. This is a prescriptive medical device, but not commonly prescribed by physicians.
For some causes of infertility, assisted natural conception can provide couples with a pregnancy rate at least as high as the one provided by fertility treatment. This is typically for couples with unexplained infertility, sperm count above 5M/ml, one tube blocked, or other mild infertility causes.
Medical treatment of infertility generally involves the use of fertility medication, medical device, surgery, or a combination of the following. If the sperm are of good quality and the mechanics of the woman's reproductive structures are good (patent fallopian tubes, no adhesions or scarring), physicians may start by prescribing a course of ovarian stimulating medication. The physician or WHNP may also suggest using a conception cap cervical cap, which the patient uses at home by placing the sperm inside the cap and putting the conception device on the cervix, or intrauterine insemination (IUI), in which the doctor or WHNP introduces sperm into the uterus during ovulation, via a catheter. In these methods, fertilization occurs inside the body.
If conservative medical treatments fail to achieve a full term pregnancy, the physician or WHNP may suggest the patient undergo in vitro fertilization (IVF). IVF and related techniques (ICSI, ZIFT, GIFT) are called assisted reproductive technology (ART) techniques.
ART techniques generally start with stimulating the ovaries to increase egg production. After stimulation, the physician surgically extracts one or more eggs from the ovary, and unites them with sperm in a laboratory setting, with the intent of producing one or more embryos. Fertilization takes place outside the body, and the fertilized egg is reinserted into the woman's reproductive tract, in a procedure called embryo transfer.
Fertility tourism is the practice of traveling to another country for fertility treatments. It may be regarded as a form of medical tourism. The main reasons for fertility tourism are legal regulation of the sought procedure in the home country, or lower price. In-vitro fertilization and donor insemination are major procedures involved.
There are several ethical issues associated with infertility and its treatment.
Many countries have special frameworks for dealing with the ethical and social issues around fertility treatment.
The consequences of infertility are manifold and can include societal repercussions and personal suffering. Advances in assisted reproductive technologies, such as IVF, can offer hope to many couples where treatment is available, although barriers exist in terms of medical coverage and affordability. The medicalization of infertility has unwittingly led to a disregard for the emotional responses that couples experience, which include distress, loss of control, stigmatization, and a disruption in the developmental trajectory of adulthood.
Infertility may have profound psychological effects. Partners may become more anxious to conceive, 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.
The emotional losses created by infertility include the denial of motherhood as a rite of passage; the loss of one’s anticipated and imagined life; feeling a loss of control over one’s life; doubting one’s womanhood; changed and sometimes lost friendships; and, for many, the loss of one’s religious environment as a support system.
Emotional stress and marital difficulties are greater in couples where the infertility lies with the man.
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.
In an effort to end the shame and secrecy of infertility, Redbook in October 2011 launched a video campaign, The Truth About Trying, to start an open conversation about infertility, which strikes one in eight women in the United States. In a survey of couples having difficulty conceiving, conducted by the pharmaceutical company Merck, 61 percent of respondents hid their infertility from family and friends. Nearly half didn't even tell their mothers. The message of those speaking out: It's not always easy to get pregnant, and there's no shame in that.
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. It has been suggested that infertility be classified as a form of disability.
Infertility is often not seen (by the West) as being an issue outside industrialized countries. This is because of assumptions about overpopulation problems and hyper fertility in developing countries, and a perceived need for them to decrease their populations and birth rates. Fertility treatments, even simple ones such as treatment for STIs that cause infertility, are therefore not usually made available to individuals in these countries.
Despite this, infertility has profound effects on individuals in developing countries, as the production of children is often highly socially valued and is vital for social security and health networks as well as for family income generation. Infertility in these societies often leads to social stigmatization and abandonment by spouses. Infertility is, in fact, common in sub-Saharan Africa. Unlike in the West, secondary infertility is more common than primary infertility, being most often the result of untreated STIs or complications from pregnancy/birth.
High costs may also be a factor and research by the Genk Institute for Fertility Technology, in Belgium, claimed a much lower cost methodology (about 90% reduction) with similar efficacy, which may be suitable for some fertility treatment.
Perhaps except for infertility in science fiction, films and other fiction depicting emotional struggles of assisted reproductive technology have had an upswing first in the latter part of the 2000s decade, although the techniques have been available for decades. Yet, the amount of people that can relate to it by personal experience in one way or another is ever growing, and the variety of trials and struggles is huge.
Other individual examples are referred to individual subarticles of assisted reproductive technology
Inhorn, Marcia C. 2003. "Global infertility and the globalization of new reproductive technologies: illustrations from Egypt." Social Science & Medicine 56(9):1837-1851. Lock, Margaret and Vinh-Kim Nguyen. 2011. An anthropology of biomedicine: Wiley-Blackwell.