Common Causes of Infertility. Infertility can be caused by problems in either the male or female reproductive system. It can also be a result of an illness or injury. For women, problems with ovulation (releasing an egg) are common. Other problems include blocked fallopian tubes, pelvic surgery and scar tissue, uterine fibroids, a narrowed cervix or lack of cervical mucus, endometriosis and cancer treatment.
1. Causes of Infertility – Ovulation Disorders
One of the most common causes of infertility is a problem with ovulation. This can happen due to a variety of reasons, such as polycystic ovary syndrome (PCOS), or it can be caused by disorders affecting the endocrine system such as hypothalamic amenorrhea.
It can also occur due to blockage in the fallopian tubes that carry sperm. This can be caused by pelvic inflammatory disease (PID), which is an infection of the uterus, fallopian tubes and/or ovaries. It can also be caused by endometriosis, which occurs when pieces of the womb lining start to grow in other places such as the ovaries or in the fallopian tubes.
Lastly, a problem with the cervix can cause infertility. This can happen if the cervix is too small or the lining is too thick to allow an egg to implant. In males, a low number of healthy sperm or a defect in the chromosomes can also lead to infertility.
2. Causes of Infertility – Endometriosis
Endometriosis is one of the leading causes of female infertility. It occurs when cells similar to those found in the uterine lining grow outside of the womb and then bleed each month. The blood cannot leave the body, so it is reabsorbed into the tissue inside the pelvis, creating inflammation, pain and scarring.
Symptoms include painful periods, pain during sex and infertility. Other symptoms include bowel issues, like constipation or diarrhea, bloating and heavy menstrual bleeding.
Doctors don’t know why women with endometriosis have fertility problems, but they suspect it has to do with inflammation, hormone changes and the ability of the fallopian tubes to carry eggs. Surgery to remove the endometrial growths improves pregnancy rates in women with mild to moderate cases. If severe, a hysterectomy (removal of the uterus and fallopian tubes) may be needed to reduce inflammation and increase fertility. Medications can also help.
3. Causes of Infertility – Polycystic Ovary Syndrome (PCOS)
One of the most common causes of infertility is polycystic ovary syndrome (PCOS). It’s a hormone disorder that affects 8-13% of reproductive-aged women. It leads to irregular periods, excess androgen levels and cysts in the ovaries. It may also increase a woman’s risk of heart disease, metabolic syndrome and endometrial cancer. It often runs in families.
For a woman to get pregnant, an egg from her ovaries has to be fertilised by sperm from her partner. The fertilised egg must then implant in the uterus. A few female fertility problems can prevent this from happening, including a blockage in the fallopian tubes or abnormalities of the uterus such as fibroids or endometriosis.
For a man to make healthy sperm, the testicles have to produce testosterone and other male hormones. A few health conditions like anemia and Cushing’s syndrome and medications such as sulfasalazine (Azulfidine) and anabolic steroids can reduce sperm production. Damage to the vas deferens from radiation or chemotherapy for cancer can also cause sperm production problems.
4. Causes of Infertility – Irregular Menstrual Cycles (IMC)
A woman who has irregular menstrual cycles is more likely to have trouble becoming pregnant than a women who has regular menstrual cycles. Irregular menstrual cycles can be caused by health problems, hormone imbalances or problems with ovulation. They can also be a sign that the uterus has not completed its job of passing an egg into the fallopian tube.
In men, infertility can be caused by problems with the ejection of semen or by sperm abnormalities such as low numbers or poor shape (morphology) and movement (motility). Semen is the fluid that contains sperm and comes from the prostate gland and seminal vesicles. Semen can become blocked by surgery on the genital tract, inguinal hernias and scar tissue from previous infections. Certain medications such as sulfa drugs and radiation can also affect male fertility.
Approximately 40% of infertility is due to problems with the female reproductive system, while the rest is due to problems in the male reproductive system or a combination of both.
5. Causes of Infertility – Age
In women, age is one of the most common causes of infertility. The number of ovarian eggs decreases as a woman gets older, and the quality of these eggs decreases too which increases the chances of chromosomal abnormalities and miscarriages. Conditions affecting the ovaries such as ovulation disorders, polycystic ovarian syndrome and hypothalamic amenorrhea can also impact fertility.
Male infertility is often caused by a low count or poor movement of sperm, which can be due to an underlying medical condition such as diabetes, low testosterone levels (male hypogonadism) and other hormonal imbalances. In addition, male infertility can be caused by problems with the ejaculate tube or testicles that block sperm from entering the fallopian tubes.
A sperm test can be performed to examine the quality and quantity of a man’s sperm. A sample of semen can be collected from the penis to check the sperm count, sperm motility and shape.
6. Causes of Infertility – Genetics
Many people think infertility is a woman’s issue, but it affects men and women of all ages. Fertility issues can be caused by both male and female factors, and in some cases are unexplained.
The most common causes of infertility are problems with ovulation or structural issues in the uterus and fallopian tubes. Symptoms of these issues can include pelvic pain, heavy or skipped periods, and irregular vaginal bleeding.
In males, the most common causes of infertility are low sperm production or blockages that prevent the delivery of sperm. These can be due to chronic illnesses, injuries or lifestyle choices. Genetics may also contribute to male infertility. This is particularly true with Klinefelter syndrome, a condition that affects the X chromosome and leads to lower levels of testosterone.
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