What causes infertility?
Infertility may be caused by a number of different factors, in either the male or female reproductive systems. However, it is sometimes not possible to explain the causes of infertility.
In the female reproductive system, infertility may be caused by:
PCOD is a hormonal condition that affects approximately 5- 10% of women in their childbearing ages (12 to 45-years). While the prevalence of PCOD differs, it affects around 9% to 22% of Indian women. The numbers are about 2% to 7% in China and Sri Lanka.
In this condition, the hormones of a woman go out of balance which creates various symptoms, including the absence of ovulation, irregular menstrual cycle, difficulty conceiving, weight gain, acne, and hirsutism. PCOD, also known as PCOS (Polycystic Ovarian Syndrome), if left untreated, can lead to further health complications, like diabetes, obesity, heart diseases, and high cholesterol.
Common Symptoms of PCOD/PCOS
The preliminary signs and symptoms of PCOD usually develop during the first cycle of menstruation at puberty. PCOD may also develop later due to increased weight over the years. There are various symptoms of PCOD. Some of the common signs are
- tubal disorders such as blocked fallopian tubes, which are in turn caused by untreated sexually transmitted infections (STIs) or complications of unsafe abortion, postpartum sepsis or abdominal/pelvic surgery;
- uterine disorders which could be inflammatory in nature (such as such endometriosis), congenital in nature (such as septate uterus), or benign in nature (such as fibroids);
- disorders of the ovaries, such as polycystic ovarian syndrome and other follicular disorders;
- disorders of the endocrine system causing imbalances of reproductive hormones. The endocrine system includes hypothalamus and the pituitary glands. Examples of common disorders affecting this system include pituitary cancers and hypopituitarism.
The relative importance of these causes of female infertility may differ from country to country, for example due to differences in the background prevalence of STIs, or differing ages of populations studied.In the male reproductive system, infertility may be caused by:
- obstruction of the reproductive tract causing dysfunctionalities in the ejection of semen. This blockage can occur in the tubes that carry semen (such as ejaculatory ducts and seminal vesicles). Blockages are commonly due to injuries or infections of the genital tract.
- hormonal disorders leading to abnormalities in hormones produced by the pituitary gland, hypothalamus and testicles. Hormones such as testosterone regulate sperm production. Example of disorders that result in hormonal imbalance include pituitary or testicular cancers.
- testicular failure to produce sperm, for example due to varicoceles or medical treatments that impair sperm-producing cells (such as chemotherapy).
- abnormal sperm function and quality. Conditions or situations that cause abnormal shape (morphology) and movement (motility) of the sperm negatively affect fertility. For example, the use of anabolic steroids can cause abnormal semen parameters such sperm count and shape.
Environmental and lifestyle factors such as smoking, excessive alcohol intake and obesity can affect fertility. In addition, exposure to environmental pollutants and toxins can be directly toxic to gametes (eggs and sperm), resulting in their decreased numbers and poor quality, leading to infertility.
