Apr 29, 2011

How In Vitro Fertilization Works

In vitro fertilization (IVF) is the joining of a woman’s egg and a man’s sperm in a laboratory dish. In vitro means “outside the body.” Fertilization means the sperm has attached to and entered the egg.

Normally, an egg and sperm are fertilized inside a woman’s body. If the fertilized egg attaches to the lining of the womb and continues to grow, a baby is born about 9 months later. This process is called natural or unassisted conception.
IVF is a form of assisted reproductive technology (ART). This means special medical techniques are used to help a woman become pregnant. IVF has been successfully used since 1978. It is most often tried when other, less expensive fertility techniques have failed.


       IVF  is  indicated  when  alternative  treatments  are  either  unlikely  to  achieve  pregnancy  or  have  failed  to  result  in  pregnancy.      
        If  you  have  blocked  fallopian  tubes  or  extensive  pelvic  adhesions  preventing  your  egg  from  entering  the  fallopian  tubes,  IVF  is  indicated.
        If  you  have  severe  endometriosis  and  are  unable  to  conceive  in  spite  of   one  or  more  operations,  IVF would  offer  a  better  chance  of  conception.

Apr 16, 2011

Six Common Misconceptions about Immunization

This list of six common misconceptions was originally written by the Centers for Disease Control and Prevention in the United States primarily for use by practitioners giving vaccinations to children in their practices.

An edited version is reproduced here as useful information for health-care workers giving vaccination as well as concerned parents. In this modern age of communication, health-care workers will encounter patients who have reservations about getting vaccinations for themselves or their children. There can be many reasons for fear of or opposition to vaccination. Some people have religious or philosophic objections. Some see mandatory vaccination as interference by the government into what they believe should be a personal choice. Others are concerned about the safety or efficacy of vaccines, or may believe that vaccine-preventable diseases do not pose a serious health risk.

All health-care workers giving vaccines have a responsibility to listen to and try to understand a patient's concerns, fears, and beliefs about vaccination and to take them into consideration when offering vaccines. These efforts will not only help to strengthen the bond of trust between staff and patient but will also help determine which, if any, arguments might be most effective in persuading these patients to accept vaccination.
These pages address six common misconceptions about vaccination that are often cited by concerned parents as reasons to question the wisdom of having their children vaccinated. If staff can respond with accurate rebuttals perhaps we can not only ease parents' minds on these specific issues but discourage them from accepting other anti-vaccine "facts" at face value. The goal of health care providers is not to browbeat parents into vaccinating, but to make sure they have accurate information with which to make an informed decision.

1. "Diseases had already begun to disappear before vaccines were introduced, because of better hygiene and sanitation."

Statements like this are very common in anti-vaccine literature, the intent apparently being to suggest that vaccines are not needed. Improved socioeconomic conditions have undoubtedly had an indirect impact on disease. Better nutrition, not to mention the development of antibiotics and other treatments, have increased survival rates among the sick; less crowded living conditions have reduced disease transmission; and lower birth rates have decreased the number of susceptible household contacts. But looking at the actual incidence of disease over the years can leave little doubt of the significant direct impact vaccines have had, even in modern times.
For example, there have been periodic peaks and valleys throughout the years, but the real, permanent drop in measles incidence coincided with the licensure and wide use of measles vaccine beginning in 1963.
Other vaccine-preventable diseases show a roughly similar pattern in incidence, with all except hepatitis B showing a significant drop in cases corresponding with the advent of vaccine use. (The incidence of hepatitis B has not dropped as much because infants vaccinated in routine programs will not be at high risk of disease until they are at least teenagers. Therefore a 15-year lag can be expected between the start of routine infant vaccination and a significant drop in disease incidence.) Haemophilus influenzae type b (Hib) vaccine is another good example, because Hib disease was prevalent until the early- to mid- 1990s, when conjugate vaccines that can be used for infants were finally developed. (The polysaccharide vaccine previously available could not be used for infants, in whom most cases of the disease were occurring.)

How Marijuana Affects the Brain

Apr 6, 2011

Vitamin D and Reducing Cancer Risk

             Given that the potential role of vitamin D in cancer prevention has been widely touted, many people were surprised that cancer-related considerations didn't figure prominently in the new Dietary Reference Intakes for vitamin D established by the Institute of Medicine (IOM). An IOM committee on which we served, charged with determining the population needs for vitamin D in North America, reviewed the evidence linking vitamin D with both skeletal and nonskeletal health outcomes. The committee concluded that vitamin D plays an important role in bone health and that the evidence provides a sound basis for determining the population's needs. For outcomes beyond bone health, however, including cancer, cardiovascular disease, diabetes, and autoimmune disorders, the evidence was found to be inconsistent and inconclusive as to causality.

             Based on vitamin D's importance to bone health, the recommended dietary allowances (RDAs) are 600 IU per day for persons 1 to 70 years of age and 800 IU per day for persons over 70 — intakes corresponding to a serum 25-hydroxyvitamin D level of at least 20 ng per milliliter (50 nmol per liter). Because of wide variation in skin synthesis of vitamin D and the known risks of skin cancer, we derived the RDAs under the assumption that sun exposure would be minimal. The committee also concluded that the prevalence of vitamin D inadequacy in North America has been overestimated. Most North Americans have serum 25-hydroxyvitamin D concentrations above 20 ng per milliliter, which is adequate for bone health in at least 97.5% of the population.
Key Points
  • Vitamin D is essential for the formation, growth, and repair of bones and for normal calcium absorption and immune function. It is obtained primarily through exposure of the skin to ultraviolet radiation in sunlight, but it can also be obtained from some foods and dietary supplements (see Questions 1 and 4).
  • Some studies suggest that higher intakes of vitamin D from food and/or supplements and higher levels of vitamin D in the blood are associated with reduced risks of colorectal cancer; however, the research results overall have been inconsistent (see Question 7).
  • Whether vitamin D is associated with reduced risks of other cancers, including breast, prostate, and pancreatic cancers, remains unclear (see Questions 8, 9, 10, and 11).
  • The National Cancer Institute (NCI) does not recommend for or against the use of vitamin D supplements to reduce the risk of colorectal or any other type of cancer (see Question 14).

    Note: The information in this fact sheet is not to be used as the basis for making health claims about products containing vitamin D.

  • What is vitamin D?
  • How much vitamin D is needed for health?
  • What are the health effects of vitamin D deficiency?
  • How much vitamin D is in fortified foods and supplements?
  • Is it safe to take vitamin D supplements?
  • Is there a role for vitamin D in reducing cancer risk?
  • Is there evidence that vitamin D can help reduce the risk of colorectal cancer?
  • Is there evidence that vitamin D can help reduce breast cancer risk?
  • Is there evidence that vitamin D can help reduce prostate cancer risk?    
  • Is there evidence that vitamin D can help reduce pancreatic cancer risk?
  • Is there evidence that vitamin D can help reduce the risk of other rare cancers?
  • What are the possible mechanisms by which vitamin D may modify cancer risk?
  • How can people get enough sunlight for vitamin D synthesis while minimizing the risk of skin cancer?
  • Does NCI recommend the use of vitamin D supplements to prevent colorectal or other cancers?         
  1. What is vitamin D?
    Vitamin D is technically not a vitamin. It is the name given to a group of fat-soluble prohormones (substances that are precursors to hormones that usually have little hormonal activity by themselves). Two major forms of vitamin D that are important to humans are vitamin D2, or ergocalciferol, and vitamin D3, or cholecalciferol. Vitamin D2 is made naturally by plants, and vitamin D3 is made naturally by the body when the skin is exposed to ultraviolet radiation (in particular, UVB radiation) in sunlight. Vitamin D2 and vitamin D3 can also be commercially manufactured. The active form of vitamin D in the body is 1,25-dihydroxyvitamin D, or calcitriol, which can be made from either vitamin D2 or vitamin D3. To make the active form, vitamin D2 and vitamin D3 are modified in the liver to produce 25-hydroxyvitamin D, which travels through the blood to the kidneys, where it is modified further to make 1,25-dihydroxyvitamin D.
    Vitamin D is involved in a number of processes that are essential for good health, including the following:
    • It helps improve muscle strength and immune function.
    • It helps reduce inflammation.
    • It promotes the absorption of calcium from the small intestine.
    • It helps maintain adequate blood levels of the calcium and phosphate needed for bone formation, mineralization (incorporating minerals to increase strength and density), growth, and repair (1–3).
    Most people get the vitamin D they need through sunlight exposure. It can also be obtained through the diet, but very few foods naturally contain vitamin D. These foods include fatty fish, fish liver oil, and eggs. Smaller amounts are found in meat and cheese. Most dietary vitamin D comes from fortified foods, such as milk, juices, yogurt, bread, and breakfast cereals. Vitamin D can also be obtained through dietary supplements. Fortified foods and dietary supplements usually contain either vitamin D2 or vitamin D3. A person’s vitamin D status is usually checked by measuring the level of 25-hydroxyvitamin D in their blood serum.
  2. How much vitamin D is needed for health?

Liya Kebede: Fighting for Maternal Health

According to Save the Children one in three women have no professional assistance during childbirth.

While the more fortunate are aided by traditional attendants many are alone during delivery putting them and their babies at grave risk.
In the age of modern medicine, why do so many mothers and newborns continue to go without proper care?

Source: http://english.aljazeera.net
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