Causes of Infertility

By August 14, 2018Infertility Causes

Infertility is common, affecting approximately one in ten women of reproductive age and the incidence is increasing. Male infertility is present in approximately 50% of these cases. More women are seeking care due to increased awareness and new highly successful infertility treatments.

Definition of Infertility

The American Society of Reproductive Medicine (ASRM) defines infertility as the inability to conceive after one year of regular, unprotected intercourse. The time is shortened to six months in women over 35 because as women age fertility can decline rapidly.

What Causes Infertility

The pages linked below have detailed information on the major causes of infertility and their treatments.

Causes of Infertility in Women

  • Ovulatory Disorders– Ovulatory disorders are a common infertility cause and include diseases like PCOS. Ovulation can often be regulated using fertility drugs, such as Clomid, Letrozole, and Metformin. If oral medications aren’t successful, IUI combined with Clomid/Letrozole and/or FSH is often the next step. Most patients become pregnant without needing IVF.
  • Endometriosis-Endometriosis can damage the fallopian tubes, ovaries, and other organs. It can also create an inflammatory environment in the pelvis. Endometriosis is often accompanied by pain during intercourse, urination, or bowel movements. Depending on its severity, it can usually be treated with drugs or laparoscopic surgery.
  • Blockage of the Fallopian Tubes– The tubes must be open for the eggs to reach the fertilization site and endometriosis is a common cause of tubal blockage. Some women also want to have a previous tubal sterilization procedure reversed. IVF usually produces excellent success rates in women with blocked or damaged tubes as the sole cause of infertility.
  • Cervical Mucous Problems– Sperm must swim through the cervical mucus to reach an egg. IUI is usually effective in treating poor cervical mucus since sperm are placed directly in the uterus.
  • Uterine Abnormalities– Women can be born with uterine abnormalities or might develop fibroids and/or polyps. Many times these conditions can be treated surgically.
  • PCOS- Polycystic ovarian syndrome leads to ovulatory irregularities and is one of the most common causes of infertility. PCOS is caused by excess androgens (male hormones) and oral Metformin is an effective treatment.
  • Miscarriage– Miscarriage is more common in older women and those who had a previous miscarriage. One cause is a genetic condition known as aneuploidy where there is an abnormal number of chromosomes. This condition increases as women age.
  • Genetic Diseases– IVF with PGD can diagnose many genetic diseases, which is especially important in high risk patients (known carriers of genetic disease). Embryos are biopsied using PGD and abnormal embryos aren’t transferred to the uterus.
  • Unexplained Infertility– When a cause of infertility can’t be identified, it is termed unexplained. IUI or IVF are often effective treatments.

Causes of Infertility in Men

  • Male Infertility– Half of all infertility cases will have varying degrees of male infertility. IUI is often effective for treating mild to moderate male infertility and IVF with ICSI is often needed when it is severe.


Can Infertility Be Treated

Studies show that early treatment by an infertility specialist results in pregnancy sooner at lower cost. Women in their thirties should see a specialist after six months (or sooner) of trying to conceive. Fertility can decline rapidly in this age group and ovarian reserve (egg quality) should be measured as soon as possible.