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Infertility Causes


The subject of infertility problems can be difficult to bring up or discuss. Because of social mores, many people feel uncomfortable talking about sexual matters, even with a fertility doctor. Furthermore, reluctance to investigate the cause of infertility may be influenced by traditional gender-based stereotypes. Many women have a strong desire to fulfill a maternal role, and the thought that they might be infertile can be very distressing. Men, on the other hand, are expected to be masculine and show little weakness, so learning about fertility problems could make them feel less virile. Despite these fears, it is essential to diagnose the causes of infertility, or finding the right fertility treatment could become an expensive guessing game.

Gender-based Infertility Problems

Until approximately 50 years ago, infertility was thought to be a woman's disease. Now, however, it is known that almost half of all fertility problems are due to male factor infertility. The most common causes of female and male infertility are discussed below.

  • Female Factor Infertility: The cause of infertility in women usually involves problems with ovulation. Signs of ovulation difficulties include non-existent or irregular menstrual cycles. Other causes of female infertility include birth defects within the uterus, uterine fibroids, and blocked fallopian tubes.
  • Male Factor Infertility: The cause of infertility in men can usually be traced to problems with the production of sperm. Men who produce no sperm suffer from a condition called azoospermia, and those with a low sperm count suffer from oligospermia. In addition, blocked reproductive tracts, malformed sperm, or inactive sperm can be a cause of male infertility.

Infertility and Age

Fertility problems can be a result of age, as both men and women's chances of conception decrease significantly with age.

  • Age and Female Fertility: Despite an increase in the percentage of middle-aged women who are successfully getting pregnant, studies have shown that women using their own eggs have a minimal chance of becoming pregnant after the age of 40. Those women over 40 who do become pregnant using their own eggs face a heightened risk of miscarriage. The reason female infertility becomes more likely over time is that egg production declines as a woman enters middle age, with many of the eggs produced containing chromosomal flaws that may cause infertility, birth defects, or miscarriage.
  • Age and Male Fertility: As more research is done on the subject, it has been determined that age can be the cause of female and male infertility. One study concluded that male infertility increased each year, resulting in an 11 percent decrease in successful pregnancies. As men age, their sperm declines in quality, volume, and motility.

Unexplained Infertility

It is believed that 10 to 20 percent of couples who are having fertility problems will receive a diagnosis of unexplained infertility. In simple terms, unexplained infertility means that after running fertility tests, the physician cannot find a medical cause for a patient's infertility. This does not necessarily indicate that there is no medical reason for the infertility. It only suggests that the medical causes of infertility that the tests specifically targeted are not the cause of the couple's infertility.

The diagnosis of unexplained infertility can be very frustrating for couples since not having a cause makes it difficult to find treatments for improving fertility. Many times additional tests may determine a cause of the infertility. There are cases, however, where there may be no real fertility problems, there may be external factors inhibiting conception including stress and personal habits, or the age of the couple may be the only cause of the infertility.

Semen Allergy

A semen allergy is a fairly uncommon cause of infertility; just 2 to 5 percent of the population experiences an allergic reaction to semen, a condition known as human seminal plasma hypersensitivity. This immune system reaction, which can occur in both men and women, produces antibodies which kill or disable sperm cells.

Semen Allergy Symptoms

Some of the symptoms of a semen allergy include:

  • Generalized itching
  • Hives
  • Swelling or blisters
  • Vaginal redness
  • Difficulty breathing (this is extraordinarily rare)
  • Infertility problems

Semen Allergies and Fertility Treatment

If you or your partner believes a semen allergy is causing fertility problems, an easy test can help. If allergic symptoms significantly diminish when using a condom during intercourse, then one or both of you may have human seminal plasma sensitivity. If it is a mild case, a doctor might recommend regular exposure to seminal fluid in order to desensitize the area.

However, more severe reactions, especially when they negatively affect fertility, require evaluation by an experienced infertility physician. Some treatment options may include:

  • Artificial Insemination
  • ICI
  • IUI
  • ICSI
  • IVF
  • Sperm Retrieval
  • Sperm Preparation

Pregnancy Statistics

Nearly 6 million pregnancies occur every year in the United States, with more than 4 million ending in live births.

Pregnancy Losses

Of the remaining 2 million pregnancies that do not end in a live birth, the pregnancy loss is due to:

  • Miscarriage: (about 600,000)
  • Termination: (about 1.2 million),
  • Ectopic Pregnancy: (about 64,000)
  • Molar Pregnancy: (about 6,000)
  • Stillbirth: (about 26,000)

Causes of Infertility

According to a report by the Society of Assisted Reproductive Technology, the causes of their infertility in couples who sought infertility treatment in 2006:

  • Male and female factor: 18 percent
  • Male factor: 17 percent
  • Female factor: 12 percent
  • Diminished ovarian reserve: 12 percent
  • Tubal factor: 9 percent
  • Ovulatory dysfunction: 6 percent
  • Endometriosis: 5 percent
  • Uterine factor: 1 percent
  • Unknown factor: 11 percent

Pregnancy Complications

Approximately 875,000 women each year experience complications during pregnancy. Annually there are about:

  • 467,000 premature births
  • 307,000 babies born with low birth weights
  • 155,000 born with birth defects
  • According to the Center for Disease Control's National Center for Health Statistics, 399 women died due to pregnancy or childbirth in 2001.

Weight Gain and Pregnancy

Data from a 2005 CDC study shows that nearly 67 percent of all pregnant women gain between 16 and 40 pounds during their pregnancy, a range that is considered healthy by most health care professionals. Only 13 percent gained less than 16 pounds, which is considered inadequate for most women, and about 20 percent gained more than 40 pounds, which is considered too much for all women.

Pregnancy Rates and Age

  • During the 1990s, the pregnancy rate for women ages 30-34 increased 3 percent, for ages 35-39 it increased 9 percent, and for ages 40-
  • A woman's chances of becoming pregnant decreases as she grows older. Younger couples are more likely to seek infertility treatment, since a healthy 30-year-old woman's chances of becoming pregnant drop from 20 percent to 5 percent by the time she is 40.
  • According to a 2005 CDC report on 422 fertility clinics, approximately 40 percent of couples that used ART were under 35 years of age, while only 9.5 percent were over 42 years of age.

Find a Fertility Specialist

If you are dealing with infertility problems, you need to meet with a doctor to determine the cause of your infertility. A qualified physician can assist you with both female and male infertility and discuss treatment plans for improving fertility. DocShop provides a search tool to assist you in finding a qualified fertility doctor near you.

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