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Infertility Drugs Infertility Drugs DefinitionInfertility drugs are medicines that help bring about pregnancy.PurposeInfertility is the inability of a man and woman to achieve pregnancy after at least a year of having regular sexual intercourse without any type of birth control. There are many possible reasons for infertility, and finding the most effective treatment for a couple may involve many tests to find the problem. For pregnancy to occur, the woman's reproductive system must release eggs regularly—a process called ovulation. The man must produce healthy sperm that are able to reach and unite with an egg. And once an egg is fertilized, it must travel to the woman's uterus (womb), become implanted and remain there to be nourished.If a couple is infertile because the woman is not ovulating, infertility drugs may be prescribed to stimulate ovulation. The first step usually is to try a drug such as clomiphene. If that does not work, human chorionic gonadotropin (HCG) may be tried, usually in combination with other infertility drugs.Clomiphene and HCG may also be used to treat other conditions in both males and females.DescriptionClomiphene (Clomid, Serophene) comes in tablet form and is available only with a physician's prescription. Human chorionic gonadotropin is given as an injection, only under a physician's supervision.Clomiphene citrate is used to increase the natural production of the hormones that stimulate ovulation in otherwise healthy women. When clomiphene is administered, the body produces higher levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), and gonadotropins. These hormones induce ovulation.Human chorionic gonadotropin (hCG) is sold under many brand names including Gonic, Pregnyl and Profasi. This hormone stimulates the gonads in both men and women. In men, hCG increases androgen production. In women, it increases the levels of progesterone. Human chorionic gonadotropin can help stimulate ovulation in women.Although some people believe that hCG can help lose weight, there is no evidence that this hormone offers any benefit in weight loss programs. It should not be used for this purpose.A number of other natural and synthetic hormones are used to induce ovulation. Urofollitropins (Fertinex) is a concentrated preparation of human hormones, while follitropin alfa (Gonal-F) and follitropin beta (Follistim) are human FSH preparations of recombinant DNA origin. Developments in this field are continuous. For example, in June 2004, the U.S. Food and Drug Administration (FDA) approved a follitropin beta injection in individualized doses for women to self-inject.Menotropins (Pergonal, Humegon, Repronex) are given with human chorionic gonadotropin to stimulate ovulation in women and sperm production in men.Recommended dosageThe dosage may be different for different patients. The physician who prescribed the drug or the pharmacist who filled the prescription will recommend the correct dosage.Clomiphene must be taken at certain times during the menstrual cycle and patients should follow directions exactly.PrecautionsSeeing a physician regularly while taking infertility drugs is important.Treatment with infertility drugs increases the chance of multiple births. Although this may seem like a good thing to couples who want children very badly, multiple fetuses can cause problems during pregnancy and delivery and can even threaten the babies' survival.Having intercourse at the proper time in the woman's menstrual cycle helps increase the chance of pregnancy. The physician may recommend using an ovulation prediction test kit to help determine the best times for intercourse.Some people feel dizzy or lightheaded, or less alert when using clomiphene. The medicine may also cause blurred vision and other vision changes. Anyone who takes clomiphene should not drive, use machines or do anything else that might be dangerous until they have found out how the drugs affect them.Questions remain about the safety of long-term treatment with clomiphene. Women should not have more than six courses of treatment with this drug and should ask their physicians for the most up-to-date information about its use.Special conditionsPeople who have certain medical conditions or who are taking certain other medicines may have problems if they take infertility drugs. Before taking these drugs, patients should tell the physician about any of these conditions:ALLERGIES. Anyone who has had unusual reactions to infertility drugs in the past should let his or her physician know before taking the drugs again. The physician should also be told about any allergies to foods, dyes, preservatives, or other substances.PREGNANCY. Clomiphene may cause birth defects if taken during pregnancy. Women who think they have become pregnant while taking clomiphene should stop taking the medicine immediately and check with their physicians.OTHER MEDICAL CONDITIONS. Infertility drugs may make some medical conditions worse. Before using infertility drugs, people with any of these medical problems should make sure their physicians are aware of their conditions:- Endometriosis
- Fibroid tumors of the uterus
- Unusual vaginal bleeding
- Ovarian cyst
- Enlarged ovaries
- Inflamed veins caused by blood clots
- Liver disease, now or in the past
- Depression.
USE OF CERTAIN MEDICINES. Taking infertility drugs with certain other medicines may affect the way the drugs work or may increase the chance of side effects.Side effectsWhen used in low doses for a short time, clomiphene and HCG rarely cause side effects. However, anyone who has stomach or pelvic pain or bloating while taking either medicine should check with a physician immediately. Infertility drugs may also cause less serious symptoms such as hot flashes, breast tenderness or swelling, heavy menstrual periods, bleeding between menstrual periods, nausea or vomiting, dizziness, lightheadedness, irritability, nervousness, restlessness, headache, tiredness, sleep problems, or depression. These problems usually go away as the body adjusts to the drug and do not require medical treatment unless they continue or they interfere with normal activities.Other side effects are possible. Anyone who has unusual symptoms after taking infertility drugs should get in touch with a physician.InteractionsInfertility drugs may interact with other medicines. When this happens, the effects of one or both of the drugs may change or the risk of side effects may be greater. Anyone who takes infertility drugs should let the physician know all other medicines she is taking.ResourcesPeriodicalsGeorgi, Kristen. "News from the FDA." Patient Care June 2004: 10.Key termsEndometriosis — A condition in which tissue like that normally found in the lining of the uterus is present outside the uterus. The condition often causes pain and bleeding.Fetus — A developing baby inside the womb.Fibroid tumor — A noncancerous tumor formed of fibrous tissue.Ovary — A reproductive organ in females that produces eggs and hormones. |