Subfertility - Causes, Diagnosis and Treatment

Subfertility – Causes, Diagnosis and Treatment

People always think of fertility to be in absolute terms like a person is either infertile or fertile. But in reality, it exists on a wide spectrum, where subfertility is at a substantial grey area, meaning it is between these two endpoints.

What Is Subfertility?

Subfertility meaning is generally any form of reduced fertility. It basically means, as a couple, you are less fertile when compared to other couples. When you are subfertile, it will take a longer time for you to get pregnant and you will encounter a longer period of trying and not conceiving. In this case, the chances of getting pregnant are still good even if you are not pregnant in the first two years.

How Subfertility Is Different from Infertility?

When you are trying to get pregnant, the distinction between infertility and subfertility matters. When a person is infertile, that person is not conceiving naturally after one year of trying and would need medical assistance to get pregnant and might not get pregnant at all without help. In the case of subfertility, there are still chances to get pregnant though it might take a longer time.

However, these terms should not be confused with a sterile person. A sterile person will not be able to get pregnant without any medical assistance while an infertile person might have a very tiny chance to get pregnant on their own.

Here is where it might get confusing: a couple is infertile when they have tried for at least one year. This is why it is recommended to see a doctor if you are not getting pregnant after a year. However, there are couples who were actually subfertile though they did not get pregnant in a year. Such couples only need more time and do not necessarily need treatment.

What Are the Causes of Subfertility?

couple checking Subfertility test results

The causes of subfertility are a little similar to those of infertility. The trouble in conceiving could lie in male infertility or female infertility or a combination of both. Certain lifestyle choices could also be the reason for subfertility. After diagnosis, many causes of subfertility can be treated, and your chances of conceiving might improve significantly. It is important to remember that there are many cases of subfertility where the cause is unknown.

The common causes of subfertility known in medical history are:

  • Sperm abnormalities (e.g., azoospermia, oligospermia, HIV, diabetes, )
  • Ovulation issues, including polycystic ovary syndrome (PCOS), premature ovarian insufficiency (POI), or diminished ovarian reserve (DOR)
  • Uterine abnormalities, like separate uterus, double uterus, or fibroids
  • Scarring around the fallopian tubes or ovaries
  • Endometriosis (minimal/mild or moderate/severe)
  • Advancing female age
  • Unexplained subfertility
  • Fallopian tube problems (eg, occlusion, adhesions, partial tubal defects, a history of gonorrhoea or chlamydia, etc.)
  • Problem with sperm delivery

Other health conditions like thyroid and adrenal gland disorders can also contribute to this condition. Women with autoimmune diseases like lupus or rheumatoid arthritis (RA) might have premature ovarian insufficiency (egg loss) that can lessen the chances of conceiving. The other biggest contributor to unexplained subfertility would be smoking (both passive and active).

Women over the age of 35 and males over the age of 40, overweight or underweight people, folks with exposure to marijuana, tobacco, alcohol, radiation, or environmental toxins, and people on certain medications are at an increased risk of subfertility.

Diagnosis of Subfertility

Doctors specialising in the field of fertility can diagnose subfertility. To start with, your doctor will collect the medical history of both partners and run a physical examination like a pelvic exam for women and an examination of the genitals for men.

Diagnosis of Subfertility

The work-up for infertility and subfertility are sort of similar, except that more attention is paid to the changing lifestyle like weight, smoking, and diet. Others include:

  • Review of a couple’s diet
  • A good medical history including the weight of a woman
  • Ovarian ultrasound
  • Menstrual abnormalities
  • Semen analysis
  • Genetic testing in the male to rule out disorders of chromosomes
  • Hormone testing in the female partner (e.g. follicle stimulating hormone and Anti-Müllerian hormone)
  • Other diagnostic techniques (like hysteroscopy and laparoscopic) might be useful if indicated.

Treatment for Subfertility

The main difference between infertile people and those that are subfertile is in how they treat the condition. In subfertile couples, medical treatment might not be so aggressive or immediate, specifically in the early stages of the problem. Many reasons for subfertility can be improved by changing their lifestyle.

If changing the lifestyle or other treatments did not improve the condition, i.e. if you did not get pregnant even after making many changes, then you could try other medical treatments including fertility medications, surgery, in-vitro fertilisation (IVF), or a combination of these treatments.

What Lifestyle Changes Can Help in Boosting Subfertility?

Lifestyle Changes Can Help in Boosting Subfertility

If you are subfertile, making a few lifestyle changes is better to try at first as it offers very few side effects and complications. A few of the lifestyle changes include:

  • Taking supplements like FertilAid for Women or Men can help to improve the chances of getting pregnant.
  • It is better to avoid smoking as it affects fertility for both men and women. In women, smoking reduces the number of eggs in the ovary at a given time (ovarian reserve) and compromises the functioning of the uterine environment and fallopian tubes.
  • Alcohol consumption should be stopped and caffeine consumption in women should be limited as it has been linked to subfertility in women.
  • You should consider exercising moderately but not excessively because this can affect the sperm count for men and the menstrual cycle for women for female subfertility.
  • The basal body temperature should be monitored very closely.
  • The frequency of sexual intercourse can be adjusted because it is found that frequent sex might further reduce an already lower sperm count.
  • Obesity can affect fertility as it leads to hormonal irregularities which can interfere with ovulation. Weight reduction is also important. Similar to being overweight, being underweight can also lead to subfertility, so weight management in case of being underweight is also important.
  • It is better to avoid sexual lubricants since it has a chance to affect sperm motility.
  • In the case of male subfertility, avoid overheating the testes through hot showers, saunas, or baths.
  • It is better to change from briefs to boxers to prevent the overheating of testes.

You are likely to get frustrated and maybe even worried if you have been trying to get pregnant for several months without being successful. This still does not mean you are infertile and need fertility treatments. It just means you might need a longer than-average time to conceive. It is best to talk to your doctor if you did not get pregnant even after a year (or 6 months if you are 35 or older). If all the test results are normal, then there is a good chance you will, within another year of trying, get pregnant. If you have decided to go for fertility treatments, then know that many subfertile couples get pregnant with basic treatments.


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Also Read:

Reasons Why You Are Not Getting Pregnant
Female Infertility: Causes, Treatment and Prevention
Home Remedies to Increase Fertility in Men and Women

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