What is Subfertility and why does it happen?

by admin-blog-kh | March 10, 2025 9:51 am

Summary

Subfertility is a condition in which a woman experiences inordinate delay in conceiving a child. It is often confused with infertility but the two are different. In this article, we will examine the causes for subfertility, why some people are more at risk of this than others, how the condition is diagnosed and finally how it is treated.

Introduction to Fertility 

Conceiving a child is the most common desire among married couples in India. According to fertility experts[1], the chances of conception are dependent on how fertile the couple are. That is, how healthy the man’s sperms are and how healthy the woman’s eggs are. And how easily can conception happen without any hurdles in the woman’s body. However, not every couple has the perfect situation, as a result, some women are not able to conceive in-spite of several attempts, or some conceive after a long delay. Accordingly, there are 3 different situations or conditions:

• Fertility: There is no biological hurdle either in the man or woman and they are able to have frequent intercourse with the desire to start a family. Normally, healthy couples should be able to conceive a child within a year of frequent sexual intercourse, around 2 to 3 times a week, timed around the woman’s fertile period in her menstrual cycle.
• Infertility: The couple have frequent sexual intercourse, that is perfectly timed. Yet, even after a year, the woman is not able to conceive. The causes could be male factors, female factors, or even unknown factors. The couple will require medical intervention in order to bear a biological child (adoption being the non-biological option).
• Subfertility: In most fertile women under 30 years of age, the woman is able to conceive, within 6 menstrual cycles as long as the couple are engaging in frequent sexual intercourse that is well-timed. However, in some women, the wait is longer, beyond 6 cycles, or 6 months, in which case the couple is considered ‘slightly subfertile’. The chances of conception are still there but there is a long period of unwanted non-conception (as opposed to wanted non-conception where the couple are delaying conception through the use of contraceptives.)

At this point, its good to note, that the above timeframes are defined for women below 30 years of age. For those above 30 years, the corresponding timeframes are longer.

Causes of Subfertility 

Fertility experts believe there are several known causes which can be broadly divided into 6 categories:

Ovulation Issues

Ovulation is a process, or phase in the menstrual cycle in which one of two ovaries release an egg, also called ovum. The egg travels down the fallopian tube where it waits for a sperm to fertilize the same (the two ovaries alternate in releasing one egg, during each cycle). There can be problems in this process, such as:

• Premature Ovarian Insufficiency or POI: Also called premature menopause, in which ovaries fail to ovulate, in-spite of the woman’s age being less than 40, due to some medical condition or cancer treatments such as chemotherapy
• Polycystic Ovary Syndrome (PCOS), a condition that prevents ovulation, or causes delayed or irregular ovulation
• Diminished Ovarian Reserve (DOR). The normal ovarian function is regulated by hormones secreted by the pituitary gland and hypothalamus region of the brain. They regulate the number of eggs that will be released by a woman in her lifetime. In some women, an aging hypothalamus or pituitary can cause a drop in the woman’s egg-count. This makes conception difficult or delayed.
• A previous ovarian surgery, which can damage the cervix and fallopian tubes

Fallopian Tube Obstruction

• If there are obstructions in the fallopian tube, the sperm cannot meet the egg so fertilization does not happen. Obstructions can be caused by:
• Endometriosis: this is a serious condition in which the endometrium, which is the lining of the uterus, is found outside the uterus and not inside as it should be. This can damage the fallopian tubes or even the ovaries, making ovulation and the egg’s journey – a challenge.
• Ectopic pregnancy[3] is a condition in which the fertilized egg gets implanted outside the uterus. This egg cannot survive for long, so a surgery may be required to terminate this pregnancy. Scar tissue from a previous surgery for ectopic pregnancy can cause subfertility.
• A history of unprotected sex leading to sexually transmitted diseases such as gonorrhoea and chlamydia
• Pelvic inflammatory disease (PID): This is an infection of the ovaries, uterus and fallopian tubes caused when sexually transmitted bacteria spread from the vagina upwards.

Uterine abnormalities

The uterus is where the fertilized embryo develops into a baby. Any abnormalities in the uterus can prevent such a growth, or even conception. Some of these defects are congenital (present since birth), or developed later. They are:

• Double uterus or didelphys uterus: here the uterus has two small cavities each with their own opening. Women with this abnormality are at the risk of subfertility, miscarriage and premature birth.
• Septate uterus: Here, a band of tissue divides the uterus into two sections. Surgery will be required to correct this defect, after which only can the woman conceive.
• Fibroids: These are benign tumours (not malignant cancers) of the muscles in the uterus. These growths can develop inside or on the uterus. A common condition, fibroids create a range of problems, one of which is blocking of the fallopian tubes.
• Bicornuate uterus: Here, the uterus has two cavities instead of one, resembling the shape of a heart. This defect reduces the chances of conception or prolongs the same.

Problems with sperm production

Sperm production in the male can be impaired due to one or more issues. This will create a low volume of sperms, preventing timely conception. Some of the issues are:

• Sexually transmitted diseases like gonorrhoea, chlamydia and HIV
• Type-2 diabetes
• Infectious diseases such as mumps
• Varicocele: A condition in which veins in the testes get enlarged. This results in low quantity and quality of sperms.
• Cancer and cancer treatments such as chemotherapy
• Congenital conditions such as Klinefelter syndrome

Problems with sperm delivery

Such problems prevent an adequate quantity of sperms and good quality of sperms from reaching the egg, for fertilization. Causes include:

• Structural abnormalities such as a blockage in the testicle
• Injury or damage to the testes from vehicle accidents, or on-field collisions in sports
• Congenital conditions such as cystic fibrosis[5]
• Cervical mucous: a thick layer of mucous can cover the cervix and prevent sperms from reaching the egg
• Premature ejaculation
• A previous vasectomy

Other Causes

Medicines: Anti-inflammatory drugs, medicines given for mental health conditions, and spironolactone

• Substance abuse: Smoking, alcoholism, drug abuse and reckless use of anabolic steroids
• Hormonal issues caused by glucocorticoid medication, Cushing’s syndrome or hormone therapy.
• Genetic disorders: such as Y-chromosome microdeletion, or myotonic dystrophy

Risk Factors 

• Age: Women over 35 years and men over 40 years are at higher risk of subfertility than their younger counterparts
• Stress: Excessive physical or emotional stress can cause issues in ovulation, sperm production and sperm delivery
• Exposure to radiation can affect sperm quality and quantity in men, and ovulation in women
• Exposure to environmental toxins, such as lead and pesticides can affect sperm quality and quantity in men
• Thyroid conditions or thyroid hormone abnormalities
• Iron overload in the body
• Cardiovascular disease, metabolic factors, high cholesterol[6] and hypertension[7]
• Trauma due to sexual and domestic violence

Diagnosis 

Tests for women 

• Blood tests to check baseline hormonal levels such as mid-luteal phase progesterone to assess ovulation, to screen infections, and to check thyroid and prolactin levels
• Transvaginal baseline ultrasound to assess the health of the reproductive organs and get the ovarian antral follicle count
• Hysterical sapingogram (HSG) to evaluate the condition of the fallopian tubes and do a pre-conception screening of the uterus for RBC count (to rule-out anaemia), vitamin D and iron levels, for diabetes, and to check immunity for rubella and chicken pox
• Anti-Mullerian Hormone Testing (AMH) or ovarian reserve testing to check the quality and quantity of eggs

Tests for men 

Semen analysis – to check quality and quantity of sperms

• Blood tests to check levels of various hormones including testosterone
• Testicular ultrasound, to check for abnormalities in the testicles
• Testicular biopsy to check for abnormalities in the testicles
• Genetic testing to look for congenital problems that can affect fertility

Treatment 

Treatment options are wide and varied depending on whether the male has the problem, or the female, and what exactly is the issue. Before putting the couple on any treatment plan, the doctors will help them boost their natural chances of conception, by making changes to their lifestyle, by constantly monitoring certain factors and getting them vaccinated for certain ailments.

At Kauvery Hospital, with branches in Chennai, Hosur, Salem, Tirunelveli, and Trichy, we provide comprehensive care and support for couples experiencing subfertility[9]. Our team of experts offers personalized diagnosis and treatment plans to enhance your chances of conception. Trust us to guide you on your journey towards parenthood with compassion and expertise.

Frequently Asked Questions

What is subfertility?
Subfertility is when conception is delayed despite regular, well-timed intercourse.

How is subfertility different from infertility?
Subfertility involves a delay in conceiving, while infertility means no conception after a year of trying.

What are the main causes of subfertility?
Causes include ovulation issues, fallopian tube blockages, uterine abnormalities, and problems with sperm production or delivery.

What risk factors increase the chances of subfertility?
Risk factors include age, stress, exposure to toxins, and certain health conditions.

How is subfertility diagnosed?
Diagnosis is done through blood tests, ultrasounds, and fertility screenings for both partners.

What treatment options are available for subfertility?
Treatments range from lifestyle changes and medications to surgical interventions, depending on the underlying cause.

 

Kauvery Hospital is globally known for its multidisciplinary services at all its Centers of Excellence, and for its comprehensive, Avant-Grade technology, especially in diagnostics and remedial care in heart diseases, transplantation, vascular and neurosciences medicine. Located in the heart of Trichy (Tennur, Royal Road and Alexandria Road (Cantonment), Chennai (Alwarpet & Vadapalani), Hosur, Salem, Tirunelveli and Bengaluru, the hospital also renders adult and pediatric trauma care.

Chennai Alwarpet – 044 4000 6000 •  Chennai Vadapalani – 044 4000 6000 • Trichy – Cantonment – 0431 4077777 • Trichy – Heartcity – 0431 4003500 • Trichy – Tennur – 0431 4022555 • Hosur – 04344 272727 • Salem – 0427 2677777 • Tirunelveli – 0462 4006000 • Bengaluru – 080 6801 6801

Source URL: https://www.kauveryhospital.com/blog/ivf-fertility/what-is-subfertility-and-why-does-it-happen/

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