Female Subfertility - Causes, Risk Factors, Diagnosis and Treatment

Introduction:

For a successful pregnancy, a woman needs to produce a healthy egg; a man needs to produce healthy sperm, followed by the fertilization of the egg by sperm and the settling of the fertilized egg in the uterus to grow into a baby. Subfertility is any reduced fertility in couples that leads to a prolonged time for conception. It has been considered a significant health issue among people worldwide. It has been associated with many reversible causes and can occur in both men and women. In men, subfertility is calculated based on the quality of semen, whereas in women, subfertility is generally associated with menstrual cycle disorders.

What Is Subfertility?

Subfertility is a type of reduced fertility seen in couples where the possibility of natural conception exists but takes longer than usual. Studies suggest couples can conceive within 12 months of regular unprotected sexual intercourse. Couples who have unprotected sexual contact regularly and do not get pregnant are considered subfertile. Few women are affected by a condition characterized by the ability to get pregnant but unable to carry the baby to a term known as impaired fecundity.

How Is Subfertility Different from Infertility?

The terms infertility and subfertility are frequently used interchangeably, but they are not the same. Subfertility is characterized by a delay in conceiving, whereas infertility is the impotence of conceiving naturally even after one year of trying. In infertility, one of the partners has a condition that makes pregnancy impossible, and hence infertility is the absolute inability to conceive. In subfertility, the couple only has difficulty getting pregnant, possibly due to medical conditions like tubal diseases or sperm deficiencies. The striking difference between infertility and subfertility is that couples with infertility can never get pregnant naturally without medical help. In contrast, couples with subfertility have chances of getting pregnant naturally without any medical intervention.

What Is Female Subfertility?

According to the World Health Organization (WHO), female subfertility is the failure to achieve a clinical pregnancy even after 12 months of regular sexual intercourse or due to impairing a woman’s reproductive capacity.

What Are the Causes of Female Subfertility?

Subfertility in couples may be due to female factors, male factors, or sometimes due to unknown reasons. The common conditions causing female subfertility are as follows:

• Ovulation Problems: The most common cause of female subfertility is problems related to ovulation. When ovulation does not take place, an egg will not be released for fertilization. The absence of egg release from the ovaries during the menstrual cycle is seen commonly in the following conditions. They are as follows:

• Polycystic Ovary Syndrome (PCOS): Polycystic ovary syndrome is a hormonal disorder characterized by the abnormal production of the male hormone androgen by the ovaries leading to irregular menstrual periods, infertility, acne, and excess hair growth. PCOS can cause irregular ovulation or prevent ovulation in women.

• Premature Ovarian Insufficiency (POI): Premature ovarian insufficiency is when the ovaries stop functioning normally before age 40, which may be due to certain medical conditions or treatments like chemotherapy and radiation therapy.

• Diminished Ovarian Reserve (DOR): Diminished ovarian reserve is a condition in women characterized by the reduced egg count in the ovaries, which decreases the ovaries' normal reproductive potential. Diminished ovarian reserve can occur due to aging, treatments like chemotherapy or radiation therapy, certain medical conditions, or previous ovarian surgeries.

• Pituitary Gland and Hypothalamus Conditions: Certain conditions of the pituitary gland and hypothalamus hinder the ability to produce hormones required to maintain normal ovarian function.

• Uterine Abnormalities: The uterus or womb is the place where a baby grows. Defects or abnormalities in the uterus can interfere with the ability to get pregnant. Some of the common uterine conditions responsible for subfertility are as follows:

  • Double Uterus: The double uterus is a congenital abnormality (structural or functional anomalies that are developed before birth) in which a female has two narrow uterine cavities, with each uterus having its ovary and fallopian tube. A double uterus has been associated with several pregnancy complications.

  • Bicornuate Uterus: A bicornuate uterus is a congenital abnormality in which the uterus is heart-shaped and has two cavities instead of one.

  • Separate Uterus: A separate uterus is a congenital abnormality in which a band of tissue runs down the center of the uterus dividing it into two sections.

• Fibroids: Fibroids are abnormal growths that develop inside or around the uterus. Fibroids may obstruct the fallopian tube or stop a fertilized egg from settling inside the uterus.

• Cervical Mucus Problems: Thick mucus present at the neck of the uterus causes difficulty for the sperm to get inside and reach the egg.

• Fallopian Tube Obstructions: Blockage in the fallopian tube can prevent the egg from reaching the sperm. It can be caused due to various reasons like pelvic inflammatory disease, scar tissue from previous surgery like surgery for ectopic pregnancy (a condition in which the fertilized egg grows outside the uterus), endometriosis (a condition in which cells similar to the uterine lining grows outside the uterus), and sexually transmitted diseases like chlamydia or gonorrhea.

• Medications: Certain medications like Spironolactone, anti-inflammatory drugs, and medicines used for treating mental health disorders may cause subfertility in women.

What Are the Risk Factors for Female Subfertility?

Certain factors that increase the risk of female subfertility are as follows:

• Women who are above the age of 35.

• Being underweight or overweight.

• Excessive smoking of marijuana or tobacco and alcohol consumption.

• Excessive emotional or physical stress.

• Certain medications.

• Radiation exposure.

• Exposure to environmental toxins like pesticides and lead.

How to Diagnose Subfertility in Women?

A fertility specialist usually makes the diagnosis of subfertility. The doctor would collect a detailed history of the sexual and medical history of both partners. The doctor would also perform a thorough physical examination of the woman, including a pelvic examination. Few tests are usually performed to diagnose female subfertility. They are as follows:

• Blood Tests: Blood tests determine the hormone levels related to ovulation.

• Transvaginal Ultrasound: This test is done to check for abnormalities in a woman's reproductive organs.

• Hysterosalpingography: Hysterosalpingography is an X-ray procedure that is used to evaluate the conditions of the uterus and fallopian tubes.

• Ovarian Reserve Testing: Ovarian reserve testing helps detect the quantity and quality of eggs.

How to Treat Subfertility in Women?

As subfertile couples have chances of getting pregnant naturally, the treatment mainly focuses on finding the underlying cause and increasing the chances of natural pregnancy. For example, if subfertility in a woman is caused due to any specific drug, stopping or changing the drug may lead to natural pregnancy. However, if there is no particular cause for subfertility in women, the common treatment methods used are as follows:

• Medications: Medications like Clomiphene and Tamoxifen are useful in stimulating the ovaries to produce eggs. In patients with diabetes and PCOS, Metformin may be given along with Clomiphene. Letrozole may be prescribed to lower progesterone levels in some patients, thereby increasing the secretion of follicle-stimulating hormone (FSH) and increasing egg production. In patients with ovulation problems due to high prolactin levels, Bromocriptine or Cabergoline may be prescribed.

• Intrauterine Insemination (IUI): Intrauterine insemination is a procedure in which the semen sample of the male partner is washed and filtered in a laboratory and inserted into the uterus using a catheter and speculum. While undergoing this treatment, the female partner should take medications that stimulate ovulation.

• Assisted Reproductive Technology (ART): ART involves handling eggs, sperm, or embryos outside the body. The different methods that come under assisted reproductive technology are as follows:

  • In Vitro Fertilization (IVF): IVF is the most common form of assisted reproductive technology. In IVF, eggs are retrieved from a woman’s ovaries and fertilized with sperm inside a laboratory. The fertilized egg is then implanted inside the uterus, which develops into a baby.

  • Intracytoplasmic Sperm Injection (ICSI): The doctor injects healthy sperm directly into a mature egg. This is highly beneficial in cases of male subfertility.

  • Donor Eggs: Donor eggs are useful for women who cannot produce healthy eggs.

  • Gestational Carrier: It is beneficial for women who do not have a functional uterus or are at high risk for pregnancy.

  • Embryo Donation: This involves donating unused embryos formed by couples during subfertility treatment to other subfertile couples. However, the baby will not be genetically related to the parents in this method.

• Lifestyle Changes: Few lifestyle changes like stopping alcohol and smoking, maintaining a healthy body weight, using ovulation predictor kits to find out the best time to have intercourse, and finding out when the woman is most fertile can increase the chances of natural pregnancy in subfertile females.

Conclusion:

Subfertility is the delay in conceiving more than the expected time. Even though it can be frustrating, certain lifestyle changes, along with treatment methods under the guidance of a doctor, would increase the chances of pregnancy. Hence, women with known medical conditions, women below 35 years who cannot conceive for more than one year, or women above 35 years who cannot conceive within six months should consult a doctor and undergo prompt treatment.