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Subfertility - What it is

Infertility or Subfertility refers to being unable to achieve pregnancy despite regular unprotected intercourse of more than 12 months. This issue is not uncommon, affecting up to 15% of couples worldwide.
Infertility may result from an issue with either the male or female partner, or it might be a combination of factors from both parties that prevent pregnancy. With careful evaluation, there are therapies available that can increase the chances of conceiving a child.

Subfertility - Symptoms

There are multiple potential causes for infertility, which can include:

Abnormalities in sperm production/function: This can be due to:
  • Genetic defects
  • Scrotal/testicular conditions: Varicocele (engorged veins within the scrotum affecting quality of sperm), previous undescended testis or testicular torsion (twisting of the testis, which affects blood flow and causing damage)
  • Hormonal imbalances such as low testosterone levels, which can contribute to impairments in sperm production
  • Drugs like anabolic steroids, certain antibiotics, or marijuana, as well as some medical treatments for cancer, like radiotherapy or chemotherapy can also affect sperm production
Obstruction in the delivery of sperm: This is due to an obstruction within the sperm ducts, limiting delivery of sperms from the testes into the semen. This could be due to genetic diseases like cystic fibrosis, or previous infections or injury.

Environmental exposures: A less common cause for infertility, but can include cigarette smoking, significant alcohol intake, malnutrition, or obesity.

Idiopathic: Up to 40% of men with infertility might have abnormal sperms, but without an obvious cause.

Subfertility - How to prevent?

Subfertility - Causes and Risk Factors

Subfertility - Diagnosis

Several tests will be performed when you seek a urologic specialist.

Semen Analysis: The fundamental evaluation for male infertility – in order to conceive a child, the male testis has to produce enough healthy sperm that is effectively ejaculated in the semen. Two or more semen samples will generally be collected, which are then analysed for several factors including sperm counts, activity, and whether the sperms have a normal shape/configuration.  

Hormone evaluation: Blood tests will be taken to determine the level of reproductive hormones including testosterone.

Other more specialised tests might be performed depending on findings from the initial evaluation, and these include:

Genetic testing: Further blood tests might be taken, especially if low sperm counts are present, to determine if an underlying genetic disorder is present.

Scrotal ultrasound: This is usually performed if there are abnormalities on the semen analysis, and is used to detect diseases associated with infertility, including varicocele and testicular cancer.

Subfertility - Treatments

Treatment can broadly be divided into lifestyle management, medications, or surgical therapy. In general, the choice of treatment depends on the underlying cause for the infertility, as well as you and your partner’s preferences. 

Lifestyle modifications: Alterations to lifestyle and/or environmental exposures can have a positive effect on sperm parameters, including -

  • Physical exercise: Regular moderate-to-high intensity exercise is recommended, as it has not only been shown to result in better sperm parameters, but improves a man’s hormonal profile as well. It also has an added benefit of decreasing the risk of several long-term chronic diseases.
  • Weight loss: Weight loss, especially for obese individuals, can have a positive effect on both sperm parameters and testosterone levels.
  • Smoking cessation
  • Moderate alcohol consumption: Heavy long-term alcohol consumption negative affects hormone levels, and should be moderated.
  • Antioxidants: There might be some improvements with sperm parameters with use of antioxidants like Vitamin C and E and coenzyme Q10, and can be taken.
  • Hormone medications: These medications are generally prescribed if the hormone evaluation is abnormal; they aim to modulate hormone levels which then improves testicular function and induces sperm production.
  • Sperm retrieval: These are techniques to obtain sperm directly from the testis or epididymis when sperms are absent in the semen. This is done via a surgical procedure, and a biopsy of the testis is usually also performed at the same time.
  • Varicocelectomy: For patients with varicocele, the blood present within the engorged veins increases the temperature of the scrotum, which compromises sperm production and fertility. A varicocelectomy might be performed, where the engorged veins are cut through a small incision in the scrotum.
Assisted Reproduction Techniques (ART): These are performed in conjunction with our colleagues from the Department of Obstetrics and Gynaecology, and includes:
  • Intrauterine insemination: Involves introduction of sperms directly into the womb of the female at the time of ovulation.
  • In-vitro fertilisation (IVF): Involves retrieval of eggs from the female, which are then inseminated with sperms obtained from the male. The fertilised embryos are then implanted into the uterus.

Subfertility - Preparing for surgery

Subfertility - Post-surgery care

Subfertility - Other Information

The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth

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