Subfertility - subfertility causes, subfertility and infertility

What is subfertility?

Subfertility refers to the failure to conceive within 1 year of unprotected regular sexual intercourse.

Subfertility is classified into two categories, namely primary subfertility and secondary subfertility. Patients with primary subfertility have no previous conception before, while those with secondary subfertility had successful conceptions before, but cannot be conceived currently.

What is the prevalence of subfertility in Hong Kong?

About 15% couples in Hong Kong suffer from subfertility. In other words, about 1 in 6 couples are affected. Besides, subfertility increases with the age of female and is affected by other factors in both men and women.

What causes subfertility?

Subfertility may be caused by multiple factors. Traditionally, Chinese people believe that women are the culprit of subfertility. However, this is a common misconception. In fact, male and female factors share similar chances in subfertility.

Female factors

  1. Advanced age: chances of subfertility increase with women’s age, especially after 35 years of age
  2. Ovulation problems: no eggs available for fertilization
  3. Tubal dysfunction: fallopian tubes may be blocked due to several reasons, common ones include inflammation of the fallopian tube (also known as salpingitis, which is usually caused by sexually transmitted diseases) and congenital tubal obstruction
  4. Ectopic pregnancy: female with past history of ectopic pregnancy may experience increased chance of ectopic pregnancy in future pregnancies.

Male factors

  1. Semen abnormalities: abnormalities in sperm morphology (shape) and motility may affect chances of conception.
  2. Lifestyle: Smoking and alcohol,
  3. Damage in reproductive systems: undescended testes, damage to the genital tract due to previous injuries or illnesses

Unexplained fertility

  • Age: female greater than 35 years of age have half the fecundity and chances of abnormal chromosome increase.
  • Prolonged time of abstains
    the rate of spontaneous conception rate decreases to less than 10% per year after 3 years of unsuccessful conception

Other causes

  • Coital difficulties
  • Immunological problems
  • Congenital abnormalities of the uterus

The information on this website is for general educational purpose only.
Readers should consult their physician before considering treatment, and should not interpret their condition solely based on the information above.