Understanding the causes of infertility in couples

The misconception that infertility is predominantly a female issue is erroneous. Male-factor infertility affects an equal number of couples as female-factor infertility. Furthermore, a quarter of couples seeking infertility treatment exhibit multiple factors or conditions that impede their reproductive ability. In recent years, age-related infertility has emerged as a pressing challenge. Peak fertility rates are observed in both sexes at 24, followed by a gradual decline. The decline becomes significant after the age of 35. Infertility can arise from various factors and can affect individuals of all sexes and age groups. In cases where a couple experiences difficulty conceiving, both partners are equally likely to be responsible. Thus, both individuals are generally evaluated for infertility if a couple is having trouble conceiving.


Infertility can arise from a multitude of potential etiologies. Consulting with a clinician specializing in infertility is recommended to identify the underlying cause of fertility issues and determine the most effective treatment options. In some instances, infertility may be idiopathic, characterized by a lack of identifiable etiology, referred to as unexplained infertility. Although it can be a source of frustration, unexplained infertility can be managed through various therapeutic modalities.

Most Common Causes of Infertility in Women:

  1. Infertility in women can have several contributing factors. The most common causes are age-related factors, tubal disease, endometriosis, endometrial polyps, ovulation disorders, and uterine fibroids.
  2. As a woman’s age increases, her chances of conceiving decrease due to a decline in the number of healthy eggs produced, especially after age 36. Tubal disease or problems with the fallopian tubes can also prevent the sperm from meeting the egg, making it difficult to conceive.
  3. Endometriosis, a condition affecting about 10% to 20% of women of reproductive age, occurs when endometrial tissues, which usually line the uterus, implant and grow outside the uterus, such as in the ovaries, fallopian tubes, or bladder.
  4. This can interfere with conception by blocking the fallopian tubes or impairing the embryo’s ability to implant
  5. Endometrial polyps refer to abnormal growths that develop in the inner lining of the uterus. If these polyps are large or multiple polyps, they can negatively impact fertility by interfering with the embryo’s ability to implant itself and develop properly. Therefore, it is highly recommended that they be removed. However, the impact of small or single polyps on fertility is still a matter of debate among medical experts.
  6. Approximately 25% of infertility cases are caused by ovulation disorders, which can result in infrequent or absent ovulation. Polycystic Ovarian Syndrome (PCOS) is one of the most prevalent disorders that affect ovulation, but other causes include ovarian insufficiency and hypothalamic amenorrhea.
  7. Uterine fibroids are non-cancerous growths in the uterus. They are ubiquitous, occurring in approximately 40% of women. However, the presence of fibroids alone doesn’t necessarily cause infertility or predispose a woman to pregnancy loss. Fibroids that distort the uterine cavity impact an embryo’s ability to implant and should be removed surgically. The impact of fibroids located elsewhere in the uterus is controversial and does not always require surgery.


Upon completing fertility testing, it has been found that nearly 20% of couples remain uncertain as to the cause of their infertility. This medical condition is referred to as unexplained infertility, which should not be confused with a lack of explanation, as routine tests may not have identified the exact cause.

It is essential to recognize that unexplained infertility can be a source of frustration and emotional distress for couples. While the absence of a definitive cause may be challenging, medical professionals must strive to provide support, guidance, and compassion to those affected.

Further research is needed to understand better the underlying factors that contribute to unexplained infertility. In the meantime, healthcare providers must work collaboratively with patients to explore alternative options and develop personalized treatment plans to help them achieve their fertility goals.


Male factor infertility is a prevalent condition that affects nearly half of all couples who experience difficulty conceiving. It is the second most significant issue after a woman’s age. The underlying causes of male infertility are diverse, and they can be attributed to problems that affect sperm production or the transport process.

  1. Various factors can cause male infertility, including azoospermia, a condition in which no sperm is produced and found in ejaculation.
  2. Antibodies that attack sperm are another cause of infertility, as immune system cells can mistakenly identify sperm as harmful invaders and attempt to eliminate them. Three main types of sperm antibodies exist, including Immunoglobulin G (IgG), Immunoglobulin A (IgA), and Immunoglobulin M (IgM).
  3. Varicocele is another cause of male infertility, in which the swelling of the veins that drain the testicles can impact sperm quality. This condition can affect one or both testes, although most men with varicocele present no symptoms.
  4. Poor-quality sperm is also a common cause of infertility. A range of health and lifestyle factors such as smoking, excessive drinking, drug use including steroids and recreational drugs, weight, body mass index, and past medical conditions such as undescended testis, hernia, STD, severe trauma, or acute viral illness can cause it.
  5. Male fertility and age are also correlated, as the quality of sperm declines after the age of 45, resulting in an increased risk of miscarriage, autism, and mental health disorders. The time it takes to get pregnant can also increase as the male partner ages.
  6. Problems with sexual intercourse can also contribute to infertility, such as erectile dysfunction, premature ejaculation, painful intercourse, anatomical abnormalities, or psychological or relationship problems that interfere with sex.
  7. Sperm transport issues are another cause, as different tubes carry sperm, and they can become blocked due to numerous causes, including infections, trauma, or abnormal development such as cystic fibrosis or similar inherited conditions.
  8. Tumors can also affect male fertility, as cancers and non-malignant tumors can impact the male reproductive organs directly or indirectly through glands that release hormones related to reproduction, such as the pituitary gland. Additionally, surgery, radiation, or chemotherapy to treat tumors can affect male fertility.
  9. Certain medications can also impair sperm production and decrease male fertility, including testosterone replacement therapy, extended-term anabolic steroid use, cancer medication (chemotherapy), certain antifungal medications, some ulcer drugs, and certain other medications.


Specific health and lifestyle factors have been identified as potential contributors to fertility problems. These factors may include

  1. Advanced maternal age, generally understood to mean women over 35, and significant deviations from healthy body weight.
  2. Exposure to chemotherapy or radiation
  3. Prolonged exposure to environmental toxins such as lead or pesticides and substance abuse, including alcohol and drug use, have all been linked to fertility issues.
  4. Other factors to consider include a history of pelvic inflammatory disease, injury to the testicles or scrotum, overheated testicles due to wearing overly tight clothing, and undescended testicles.
  5. Finally, it’s worth noting that smoking cigarettes has also been associated with increased fertility problems.

Given the potentially significant impact of these factors on fertility, individuals and healthcare providers must remain vigilant in mitigating risk and promoting optimal health outcomes. By carefully monitoring and addressing potential risk factors, we may be able to improve the chances of successful conception and healthy pregnancies for those who may be struggling with fertility issues.

Infertility can be a challenging experience that causes considerable stress and anxiety. If you are over the age of 35 years and have not been successful in conceiving after 12 months of trying, it is advisable to consult your healthcare provider. Our team of fertility experts at 9M Fertility centres across Hyderabad, Pune and Bhubaneshwar, can offer assistance in identifying the underlying cause of your infertility and developing a customized treatment plan to address it. Maintaining a positive outlook during this process is crucial, as most individuals can achieve successful conception with proper treatment.



Leave a Comment

Your email address will not be published. Required fields are marked *