There are many causes of infertility, which can be defined as” difficulty in becoming pregnant (conceiving) despite having regular sex when not using contraception for one year”.
Age is one of the most determining factors. Older women tend to be less fertile than younger women. The fall off of fertility seems to be greatest once you are past your middle 30s and more severe is the fall beyond 40years. Stress is another factor that can also affect libido and leads to anxiety and indirectly lead to fertility issues.
Ovulation problems in women
Not producing eggs (ovulating) is the cause of problems in about 1 in 4 couples. In some women, this is a permanent problem. In some it only happens from time to time: some months ovulation occurs and some months it doesn’t. There are various causes of ovulation problems including:
- Polycystic ovary syndrome (PCOS).
- Hormone problems like thyroid disorders ,prolactin disorders etc
- Being very underweight or overweight
- .Premature ovarian insufficiency.
- Some women with medical disorders, such as uncontrolled diabetes, cancers and chronic kidney disease, may not ovulate.
- Drugs—chemotherapeutic drugs
- Various other problems with the ovary such as certain genetic problems.
The fallopian tube, cervix, or uterine problems
These are the cause in about 2 or 3 in 10 couples with infertility. Problems include:
- Endometriosis, which causes about 1 in 20 cases of infertility.
- Pelvic inflammatory disease (PID).
- Previous surgery to the Fallopian tubes, cervix, or uterus.
- Large fibroids.
Causes of infertility in men
In some couples, the male partner may be responsible alone(50%) or in combination with the female partner. The most common reason for male infertility is a problem with sperm, due to an unknown cause. The sperm may be reduced in number(count), less able to swim forwards (motility), and/or be abnormal in their form(morphology).
There are various factors that may affect sperm production and male infertility. These include:
- Current or past infection of the testicles (for example, mumps).
- Current or past infections of another part of the sperm-producing system, such as gonorrhoea or other sexually transmitted infections.
- Tumours of the testicles.
- Testicles that haven’t dropped (descended) properly.
- Certain drugs like sulfasalazine, nitrofurantoin, tetracyclines, cimetidine, colchicine, allopurinol, some chemotherapy drugs, and anabolic steroids.
- Scarring from previous operations (such as an inguinal hernia repair) may block the ducts which carry sperm, and affect fertility.
- A varicocele may possibly affect male fertility.
- Hormonal problems such as Cushing’s syndrome or hyperprolactinaemia.
- Genetic conditions such as Klinefelter’s syndrome and Kallman’s syndrome.
- Obesity may reduce fertility in men.
No cause can be found in about 1 in 4 couples with infertility.