Fertility

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Fertility

Fertility is defined as the quality of being fruitful and productive. Physiologically, it refers to the ability to conceive a child. A closely related term, fecundity, refers to the capability of conceiving and bearing live offspring, though in everyday language the two terms are often used synonymously. Before people had a better understanding of human reproduction, the term fertility was applied exclusively to women, but today the term may apply to either sex. Virility is a masculinized version of fertility and suggests robust sexual activity and the ability to impregnate women. Virility is also associated with culturally determined images of masculine appearance and behavior. In certain cultures (especially Latino), machismo, or an exaggerated sense of masculinity, is not only acceptable but often expected in virile men.

Biologically, women become fertile at puberty (usually between ages ten and thirteen) when the ovaries begin functioning. Each month, roughly corresponding to day fourteen of her menstrual cycle, the woman ovulates (releases an egg). It is during this time that she is most fertile. If sperm is present fertilization may occur in the fallopian tubes with the resulting embryo implanting in the uterus. Females continue to release one egg each month throughout their reproductive years, though after the age of thirty a woman's fertility begins to diminish. Infertility affects only 5 percent of women in their thirties; however, by the time they reach their thirties, they can expect a 25 percent chance of infertility, which is defined by the inability to conceive a pregnancy after one year of unprotected sex (six months if she is thirty or older). The chances of delivering a healthy baby (because of miscarriage or other medical conditions) are even less. The onset of menopause near the age of fifty marks the cessation of the woman's menstrual cycles and her ability to conceive a child. Men, however, remain sexually fertile throughout most of their adult life. After the onset of puberty, when the testicles begin functioning, males are able to produce a continual supply of sperm capable of impregnating a woman (though male fertility does diminish as men approach advanced years).

Most couples have no trouble conceiving. In the United States 85 percent of women will get pregnant within one year of unprotected sexual intercourse. Of the remaining 15 percent, most are not entirely infertile (very uncommon) but, rather, subfertile, meaning they may need medical or technological assistance to conceive a child. It is estimated that at the start of the twenty-first century 2.4 million couples worldwide experience infertility, and the number appears to be growing. Essentially, each step in the reproductive process contributes to fertility, and anything that interrupts or interferes with those processes may cause difficulty for couples trying to conceive a child. The two most common reasons for infertility are hormonal conditions (in either sex) or anatomical abnormalities (including blockages in the reproductive organs caused by disease).

Cultural influences, as well, including nutrition, sexual behavior, timing, economics, lifestyle, and emotions, may also influence fertility. In addition, the deferment of childbearing due to later age of marriage, the availability of reliable birth control and abortion, the changing roles of women in the workplace, and the tendency to delay childbearing until later in the marriage account for the increase in infertile couples.

FOLK REMEDIES FOR INFERTILITY

Primitive cultures, which lacked a full understanding of reproduction, often developed rituals and ceremonies to ensure that both the land and the people would be fruitful. Dances, prayers, sacrifices, and sacred rites were performed to try to influence those aspects of nature that could not be otherwise explained or controlled. Ancient people often personified the concept of fertility in the form of female deities such as the Greek's Aphrodite, the Roman's Venus, the Teutonic Freyja, the Irish's Brigit, and the pagan's Mother Nature. Societies as diverse as Incan, Babylonian, Slavonic, and Iroquoian believed that fertility of people and land were controlled by female deities and priestesses.

Though feminized versions of fertility were common, male images were also involved in fertility rituals. Some ancient cultures scattered the testicles and penises of animals on the fields to encourage crop fertility in a conflation of human and agricultural regeneration. Phallic symbols were thought to promote fertility, and many early Romans carried amulets that depicted phalluses of priapic proportions. In India early cultures believed that a female virgin would be fruitful if she were deflowered with a lingam, a stone in the shape of a phallus that symbolizes Shiva, the god responsible (among other things) for creation. Human and animal sacrifices and ritual prostitution were all performed in an attempt to bring fertility to the community. Many modern European and North American rituals and celebrations were born from early pagan fertility rites. The tradition of Easter eggs arises from two pagan symbols of fertility: the egg, and rabbits (which procreate efficiently and prodigiously). Phallic maypoles (some even included two rings representing the testicles) were erected for young couples to dance around in traditional spring rituals meant to assure a bountiful harvest.

Early people also sought herbal remedies to assure fertility. Pagans believed that mistletoe, because the parasitic plant grew halfway between Earth and the heavens, never touching the ground, contained mystical powers, which, among other things, could promote fertility. To maintain its potency the druids cut mistletoe with a gold sickle, being careful to keep it from touching the ground where it would lose its power. Because the plant was green year round, druids thought it contained the spirit of Mother Nature. Couples hoping to conceive kissed under its bough and took away a berry (which contained juices very similar to semen) each time until all the berries were gone and the mistletoe lost its potency.

Other folk beliefs held that mandrake root could cure sterility and act as an aphrodisiac to promote sexual vigor. In the Bible the long-barren Rachel eats mandrakes in order to conceive a child (Genesis 30). Jewish people called the fruit of the mandrake dudaim (or love apple) because of its purported ability to cure infertility. Ancient Greeks steeped it in vinegar or wine to make an infusion, which they drank. Even in the early twenty-first century in many Middle Eastern cultures, dried mandrake roots are carried as a charm to promote fertility. Yams have been long thought to promote both fertility and the incidence of twins in humans because they contain chemical compounds that are similar to female sex hormones. Ginseng, another home remedy for infertility and sexual dysfunction, is used by many couples to improve male sexual function (leading it to be called the herbal Viagra) and female fertility.

EUROPEAN AND NORTH AMERICAN MEDICINE AND TREATMENT OF INFERTILITY

Modern treatment for infertility consists of hormonal and reproductive technologies. Fertility drugs such as Clomid and Pergonal stimulate the follicles (the site of the egg in the ovaries) to mature and release one or more eggs. Artificial insemination, a practice dating back to the eighteenth century, has improved to allow for the concentration of sperm in men with low sperm counts (and in cases where there is an incompatibility between the man's sperm and the woman's cervical mucous). Artificial reproductive technologies (ART) have been developed that involve the surgical removal of the egg from the woman's ovaries. The most commonly known of these techniques is in vitro fertilization (IVF), in which the woman's egg is isolated in a laboratory Petri dish, mixed with sperm, and, if fertilization occurs, the resulting zygote (or very early stage of an embryo) is injected into the woman's uterus (which has been hormonally primed to accept a pregnancy) where it will implant. The procedure is expensive and time-consuming, but it offers the chance for many infertile couples to conceive.

There are numerous variations of the in vitro technique, such as gamete intrafallopian transfer (GIFT) where the embryo is returned to the fallopian tubes instead of the uterus in an attempt to let the process proceed as naturally as possible after fertilization. In cases where a woman's ovaries remain able to produce eggs but the egg is unable to travel to the uterus (because of disease or prior surgery), a surrogate woman may be contracted to carry the pregnancy to term for the infertile couple. The surrogate then legally relinquishes parental rights to the child after birth. In addition, a donor embryo may be implanted into an infertile woman. Technology offers many alternatives to natural conception, with resulting pregnancy rates equalling (if not better than) that of fertile couples. Pregnancies conceived by artificial reproduction technologies have a high risk (up to 35% of the time) of multiple births. It is estimated that at the beginning of the twenty-first century, about 1 percent of all births in the United States are the result of ART technology, and in other countries, such as Denmark, the rate is as high as 4 percent.

EFFECTS OF ATTITUDES ABOUT FERTILITY ON POPULATIONS

Though the fertility rate (a measure of the number of children born per woman) has generally been used as an indicator of population growth, it is becoming less reliable in many Asian countries such as China and India, which have very strong population control laws and offer incentives to control their exploding population growth. China's one-child policy limits each family to one offspring. Because of a cultural preference for boy children, there is a significant decrease in the number of girls born (because of selective abortion or infanticide). The practice of eliminating girl fetuses and babies is so widespread that it has created a lopsided gender ratio that threatens the social balance of Chinese society. The Chinese government is now trying to address the situation by proposing financial incentives to encourage couples to keep female children.

see also Contraception: I. Overview; Infertility; Reproduction (Procreation).

BIBLIOGRAPHY

Mystical Rites and Rituals: Initiation and Fertility Rites, Sacrifice, and Burial Customs, Incantation and Ritual Magic. 1975. London: Octopus Books, Phoebus.

Nevid, Jeffrey S; Louis Fichner-Fathus; and Spencer A. Rathus. 1995. Human Sexuality in a World of Diversity. 2nd edition. Boston: Allyn and Bacon.

Philips, Kim. Sexualities in History. 2001. New York: Routledge.

Smith, Anthony. The Body. 1986. Harrisonburg, VA: Donnelley & Sons.

Speroff, Leon; Robert H. Glass; and Nathan G. Kase. 1994. Clinical Gynecologic Endocrinology and Infertility. 5th edition. Baltimore, MD: Williams & Wilkins.

                                          Diane Sue Saylor