Causes of Female Infertility

Infertility is defined as the inability to become pregnant after a year or more of attempting to conceive. If a woman is over the age of 35, six months or more of trying to get pregnant may be an indicator of infertility. Women who are able to get pregnant, but can’t stay pregnant, could also be infertile.

The Pregnancy Process

In order for a pregnancy to be successful, each of the following four steps must occur:

  1. Ovulation: An egg must be released from one of the ovaries.
  2. Fertilization: A man’s sperm must combine with the female’s egg.
  3. Movement Through Fallopian Tube: The fertilized sperm must successfully travel through one of the fallopian tubes toward the uterus.
  4. Implantation: The fertilized egg has to attach to the inside of the uterus.

Causes of Infertility in Women

The female reproductive system is so complex that a large number of factors could affect a woman’s fertility.

Disrupted Ovulation 

If the ovaries are not releasing an egg, there is nothing for the sperm to fertilize. In many cases, issues with ovulation are the cause of infertility in women. The most common causes of disrupted ovulation include:

  • Polycystic Ovarian Syndrome. PCOS occurs when a woman’s estrogen and progesterone levels are imbalanced. Over time, this causes small cysts to develop on the ovaries. This syndrome makes it difficult to get pregnant because it has the potential to stop menstruation.
  • Hypothalamic Dysfunction. Hypothalamic dysfunction occurs when when FSH and LH, the two hormones responsible for ovulation, become imbalanced. This can be caused by extremely high or low weight and severe stress.
  • Premature Ovarian Insufficiency. This occurs when a woman under the age of 40 experiences a decline in ovarian function. The results are similar to early menopause.
  • Menopause. Menopause is the natural decline in ovarian function that typically occurs around the age of 50.

Fallopian Tube Swelling or Blockage 

The fallopian tubes are responsible for carrying the fertilized egg to the ovaries. When the egg cannot move through the fallopian tubes, it cannot attach to the wall of the uterus.

  • Pelvic Inflammatory Disease. Typically caused by an untreated STI, pelvic inflammatory disease is an infection that affects the uterus and fallopian tubes.
  • Previous Pelvic Surgery. If surgery was performed on or near the fallopian tubes, especially in the case of an ectopic pregnancy, this disruption may lead to an increased risk of infertility.

Uterine Dysfunction 

The uterus nurtures the fertilized ovum as it develops into a fetus and continues to do so until the baby is ready for birth. The most common uterine causes of infertility include:

  • Uterine Fibroids. Despite being mostly symptomless, these non-cancerous tumors can grow into the walls of the uterus and prevent a fertilized egg from attaching.
  • Endometriosis. The tissue that lines the uterus may begin to grow in other areas of the reproductive system. This condition often times results in ectopic pregnancies.

What Increases Risk of Female Infertility?

There are several contributing factors to a woman’s reproductive function. While some causes cannot be prevented, reducing or eliminating certain behaviors can potentially improve chances of becoming pregnant.

  • Age. Women over the age of 35 tend to have more fertility issues than those 34 or younger.
  • Smoking. The toxins in cigarettes can have a negative effect on reproductive health.
  • Alcohol Consumption. Studies have shown a link between heavy alcohol consumption and decreased female fertility.
  • Extreme Weight Gain or Loss. If a large amount of weight is gained or lost, especially in a short period of time, hormones levels can become imbalanced.
  • High stress. Over a period of time, high stress has the ability to affect hormone levels.

Learn about infertility treatment options.