Understanding Infertility

If you’re reading this article, you may be among the one in six adults worldwide who have experienced infertility. Whether you’ve recently been diagnosed or are concerned about your reproductive health, know that you’re not alone on this journey.

Infertility can be an emotionally challenging experience, often accompanied by feelings of frustration, grief, and uncertainty. While the medical aspects are important to understand, it’s equally essential to acknowledge the emotional toll this process can take. This guide aims to provide evidence-based information about infertility while recognizing the complex emotions you may be experiencing.

What Is Infertility?

The American Society for Reproductive Medicine (ASRM) defines infertility as “a disease, condition, or status characterized by the inability to achieve a successful pregnancy based on a patient’s medical, sexual, and reproductive history, age, physical findings, diagnostic testing, or any combination of those factors.”

For clinical purposes, infertility is generally defined as:

• For women under 35: Not conceiving after 12 months of regular, unprotected intercourse
• For women 35 and older: Not conceiving after 6 months of regular, unprotected intercourse

It’s important to understand that infertility doesn’t necessarily mean you can never have children. Rather, it indicates there may be factors making conception more challenging.

Important Related Terms

Several terms are commonly used when discussing fertility:

• Fecundity: The capacity to have a live birth.
• Fecundability: The probability of achieving pregnancy in a single menstrual cycle with adequate sperm exposure that results in a live birth.
• Fertility: The ability to have a clinical pregnancy.
• Primary infertility: Infertility in a couple who has never had a child.
• Secondary infertility: Infertility in a couple who has previously conceived.

How Common Is Infertility?

According to the World Health Organization (WHO), approximately one in six adults worldwide has experienced infertility at least once in their lifetime. This prevalence is similar across both high-income countries (17.8%) and low/middle-income countries (16.5%).

Several factors influence infertility prevalence:

• Age: Analysis from the 2016 Global Burden of Disease Study found females aged 20-24 had the lowest rates of infertility (approximately 3%), while those aged 35-39 had the highest rates (approximately 5.5%).
• Prior pregnancies: Nulliparous individuals (those who have never been pregnant) as a group had more than twice the prevalence of infertility compared with parous individuals (13% versus 6%), with nulliparous individuals aged 35-39 having a nearly fourfold increased prevalence compared with their parous counterparts (27.2% versus 7%).
• Access to healthcare: The ability to access reproductive health services is associated with reduced prevalence of infertility, likely through improved screening and treatment of gynecologic disease and infection.

Understanding Normal Fertility

To understand infertility, it helps to know what “normal” fertility looks like. Most pregnancies occur within the first six menstrual cycles of trying to conceive. For a couple with no fertility issues, the chance of conception in any given month (called “fecundability”) is about 15-25%.

However, this doesn’t mean that all couples who don’t conceive within six months have a fertility problem. Many healthy couples may take longer to conceive naturally. Studies show that 80-90% of couples will conceive within 12 months of regular, unprotected intercourse.

Factors that influence normal fertility include:

• Female age: A woman’s fertility begins to decline significantly starting around age 32, with a more dramatic decrease after age 37.
• Frequency and timing of intercourse: Conception is most likely when intercourse occurs in the 2-3 days leading up to and including ovulation.
• General health factors: Nutrition, weight, stress levels, and certain medical conditions can impact fertility.

What Causes Infertility?

Infertility is rarely attributable to just one person in a relationship. According to a World Health Organization study of 8500 infertile couples, causes of infertility typically break down as follows:

• Female factors only: 37%
• Male factors only: 8%
• Both male and female factors: 35%
• Unexplained infertility: 5%
• Other/pregnancy achieved during evaluation: 15%

Common Causes in Women

1. Ovulatory Disorders (25% of female infertility)

Ovulatory disorders prevent regular release of eggs from the ovaries. The World Health Organization classifies these disorders into three categories:

• WHO Class 1 (5-10%): Hypogonadotropic hypogonadal anovulation, such as functional hypothalamic amenorrhea from excessive exercise, low body weight, or stress.
• WHO Class 2 (70-85%): Normogonadotropic normoestrogenic anovulation, most commonly polycystic ovary syndrome (PCOS).
• WHO Class 3 (10-30%): Hypergonadotropic hypoestrogenic anovulation, such as premature ovarian insufficiency or primary ovarian failure.

Symptoms of ovulatory disorders may include irregular or absent menstrual periods, although some women with ovulatory disorders still have regular cycles.

2. Tubal Factors (22% of female infertility)

Damaged or blocked fallopian tubes prevent sperm from reaching the egg or the fertilized egg from reaching the uterus. Causes include:

• Prior pelvic inflammatory disease (often from untreated sexually transmitted infections)
• Previous abdominal or pelvic surgery
• Severe endometriosis
• Ectopic pregnancy
• Congenital abnormalities

Most women with tubal blockage have no symptoms, making regular screening for sexually transmitted infections important for prevention.

3. Endometriosis (15% of female infertility)

Endometriosis occurs when tissue similar to the uterine lining grows outside the uterus. It can affect fertility through multiple mechanisms:

• Anatomical distortion from pelvic adhesions
• Damage to ovarian tissue
• Altered immune environment affecting fertilization and implantation
• Impaired egg quality

Symptoms may include painful periods, pain during intercourse, chronic pelvic pain, or abnormal bleeding, though some women have no symptoms.

4. Uterine Factors

Several uterine conditions can impact fertility:

• Fibroids (leiomyomas): Benign muscle tumors that can distort the uterine cavity or block the fallopian tubes, particularly submucosal fibroids that project into the uterine cavity.
• Uterine polyps: Small, usually benign growths that protrude into the uterine cavity.
• Uterine anomalies: Congenital malformations such as a septate or bicornuate uterus.
• Intrauterine adhesions (Asherman syndrome): Scar tissue inside the uterus, often from prior surgeries.

5. Cervical Factors (3% of female infertility)

Issues affecting the cervix can include:

• Abnormal cervical mucus that may impede sperm transport
• Previous treatments for abnormal cervical cells (like LEEP or cone biopsy)
• Structural abnormalities

6. Age-Related Decline in Ovarian Reserve

A woman is born with all the eggs she’ll ever have, and both the quantity and quality of these eggs decline with age:

• At birth: 1-2 million eggs
• At puberty: 300,000-500,000 eggs
• By age 37: Accelerated decline in both quantity and quality
• By age 40: Often significant reduction in fertility potential

The decline in egg quality is primarily due to an increase in chromosomal abnormalities as women age.

Common Causes in Men (26% of all infertility cases)

Male factor infertility is categorized by where in the process the issue occurs:

1. Pre-testicular Causes

Hormonal imbalances affecting sperm production:

• Hypothalamic or pituitary disorders
• Androgen resistance
• Thyroid or adrenal disorders
• Use of anabolic steroids

2. Testicular Causes

Problems with the testes themselves:

• Varicocele: Enlarged veins in the scrotum that raise testicular temperature (found in about 40% of men with fertility problems)
• Genetic disorders (Klinefelter syndrome, Y chromosome microdeletions)
• Undescended testicles (cryptorchidism)
• Testicular trauma or torsion
• Mumps orchitis
• Exposure to toxins, radiation, or chemotherapy

3. Post-testicular Causes

Issues with sperm transport or function:

• Obstructions in the epididymis, vas deferens, or ejaculatory ducts
• Absence of vas deferens (often associated with cystic fibrosis gene mutations)
• Retrograde ejaculation
• Sexual dysfunction (erectile dysfunction, ejaculatory problems)
• Antibodies against sperm

4. Idiopathic Male Infertility

In about 30-40% of male infertility cases, the exact cause cannot be identified despite normal physical examination and hormonal studies.

Combined Factors

Both partners may have fertility issues that, while not significant enough to cause infertility individually, together reduce the probability of conception.

Unexplained Infertility

In about 10-20% of couples, no specific cause is found despite comprehensive testing. This is called “unexplained infertility.” This diagnosis can be frustrating, but it doesn’t mean treatment isn’t possible. Many couples with unexplained infertility still conceive with treatment or, sometimes, spontaneously over time.

When Should You Seek Help?

The timing of an infertility evaluation depends primarily on the woman’s age and any known health factors:

• Women under 35: After 12 months of trying to conceive
• Women 35-40: After 6 months of trying to conceive
• Women over 40: After 3 months or immediately
• Any age with known fertility risk factors: Immediate evaluation is appropriate

Risk factors that might warrant earlier evaluation include:

• Irregular or absent menstrual periods
• Known or suspected endometriosis
• Known or suspected tubal disease or uterine abnormalities
• History of pelvic infections or surgeries
• Previous cancer treatment
• Male partner with known fertility issues
• History of recurrent pregnancy loss

The Infertility Evaluation Process

A comprehensive fertility evaluation typically examines both partners simultaneously. Here’s what to expect:

For Women

1. Medical History and Physical Exam

Your doctor will ask about:

• Menstrual history (regularity, duration, flow, pain)
• Previous pregnancies and their outcomes
• Sexual history (frequency, timing, difficulties)
• Previous contraceptive use
• Medical conditions and medications
• Surgical history
• Family history of reproductive issues
• Lifestyle factors (smoking, alcohol, caffeine, exercise, stress)

The physical exam may include:

• Checking for signs of hormonal imbalances (excess hair growth, acne, thyroid abnormalities)
• Pelvic examination to check for abnormalities of the vagina, cervix, uterus, or ovaries
• Assessment of body mass index (BMI)

2. Ovulation Assessment

Several methods can determine if and when you’re ovulating:

• Menstrual history: Regular cycles with symptoms like breast tenderness or mild cramping mid-cycle suggest ovulation is occurring.
• Basal body temperature (BBT) charting: A slight temperature rise (0.4-1.0°F) occurs after ovulation.
• Ovulation predictor kits: These detect the luteinizing hormone (LH) surge that triggers ovulation.
• Mid-luteal progesterone level: A blood test about 7 days before your expected period can confirm ovulation; levels >3 ng/mL indicate recent ovulation.
• Endometrial biopsy: Rarely used today, this was historically done to evaluate the uterine lining for evidence of ovulation.

3. Ovarian Reserve Testing

These tests assess the quantity of remaining eggs:

• Anti-Müllerian hormone (AMH): A blood test that can be done at any time during the menstrual cycle; higher levels indicate better ovarian reserve.
• Day 3 follicle-stimulating hormone (FSH) and estradiol: Blood tests done on the third day of your period; lower FSH (<10 mIU/mL) and estradiol (<80 pg/mL) levels suggest good ovarian reserve.
• Antral follicle count: An ultrasound examination to count small follicles in the ovaries; more follicles indicate better ovarian reserve.
• Clomiphene citrate challenge test: Less commonly used now, this test involves taking clomiphene for 5 days and measuring FSH levels before and after.

It’s important to note that while these tests can predict how you might respond to fertility treatments, they cannot necessarily predict your chances of natural conception.

4. Tubal Patency Assessment

Tests to evaluate whether your fallopian tubes are open include:

• Hysterosalpingogram (HSG): X-ray procedure where dye is injected through the cervix to visualize the uterine cavity and fallopian tubes.
• Sonohysterogram or Hysterosalpingo-contrast sonography (HyCoSy): Ultrasound procedure where saline or other contrast is injected through the cervix to evaluate the uterine cavity and fallopian tubes.
• Laparoscopy with chromopertubation: Surgical procedure where dye is injected through the cervix while the doctor directly visualizes the fallopian tubes through a laparoscope to check for blockages.

5. Uterine Evaluation

Methods to assess the uterine cavity for abnormalities include:

• Transvaginal ultrasound: Basic imaging of the uterus and ovaries.
• Saline infusion sonohysterography: Ultrasound with saline injected into the uterus to better visualize the cavity.
• Hysteroscopy: Procedure where a tiny camera is inserted through the cervix to directly visualize the uterine cavity.

6. Additional Testing

Depending on your situation, your doctor might recommend:

• Thyroid function tests: Thyroid disorders can affect fertility.
• Prolactin level: Elevated prolactin can affect ovulation.
• Testing for other hormonal imbalances: Such as androgens in women with PCOS.
• Genetic testing: If certain genetic conditions are suspected.
• Tests for immunological factors: In select cases.

For Men

1. Semen Analysis

This is typically the first test performed for male partners and evaluates:

• Volume: Normal is 1.5 mL or more
• Concentration: Normal is 15 million sperm per milliliter or more
• Motility: Normal is 40% or more sperm with forward progression
• Morphology: Normal is 4% or more sperm with normal shape
• Other factors: White blood cells, agglutination (clumping), viscosity

Abnormal results should be confirmed with at least one additional analysis, typically 2-3 months apart.

2. Hormone Testing

If the semen analysis shows abnormalities, blood tests may be done to check:

• Testosterone
• Follicle-stimulating hormone (FSH)
• Luteinizing hormone (LH)
• Prolactin
• Thyroid hormones

3. Genetic Testing

This may be recommended in cases of severe male factor infertility:

• Karyotype (chromosome analysis)
• Y-chromosome microdeletion analysis
• Cystic fibrosis gene mutation testing (if absence of vas deferens is found)

4. Specialized Tests

In some cases, additional testing might include:

• Scrotal ultrasound: To look for varicoceles or other abnormalities
• Testicular biopsy: Rarely performed, to evaluate sperm production
• Post-ejaculatory urinalysis: To check for retrograde ejaculation
• Sperm function tests: Such as DNA fragmentation or sperm penetration assays

Treatment Options

Treatment depends on the underlying cause of infertility and may include:

Lifestyle Modifications

Weight Management

Both underweight and overweight conditions can affect fertility:

• Underweight: Women with BMI <18.5 may have hypothalamic amenorrhea that improves with weight gain.
• Overweight/Obesity: PCOS symptoms often improve with weight loss; studies show that just a 5-10% weight loss in women with PCOS can restore ovulation in 55-100% of women within six months.

Smoking and Vaping Cessation

Research clearly shows that smoking negatively impacts fertility:

• In women: Earlier menopause, reduced ovarian reserve, impaired fallopian tube function
• In men: Reduced sperm count, motility, and normal forms; increased DNA damage

Moderate Alcohol and Caffeine

• Alcohol: Excessive consumption (>8 drinks/week) may reduce fertility in women
• Caffeine: Very high intake (>500 mg/day, or about 5 cups of coffee) may slightly reduce fertility

Timing of Intercourse

• Having intercourse every 1-2 days during the fertile window maximizes chances
• Using ovulation prediction kits can help identify the fertile window
• Lubricants that are “fertility friendly” are preferable, as some lubricants can impair sperm movement

Medical Treatments

For Ovulatory Disorders

1. Clomiphene Citrate: 
   • Oral medication that stimulates ovulation
   • Success rates: 60-80% ovulation rate, 30-40% pregnancy rate within 6 cycles
   • Risk of multiple pregnancy: 5-8% (mostly twins)
   • Common side effects: Hot flashes, mood swings, headaches, visual disturbances
2. Letrozole (Aromatase Inhibitor): 
   • Alternative oral medication for ovulation induction
   • Often preferred for women with PCOS (higher live birth rates than clomiphene)
   • Lower multiple pregnancy rates than clomiphene
   • Common side effects: Joint/muscle pain, hot flashes, headaches
3. Gonadotropins: 
   • Injectable hormones (FSH, LH) that directly stimulate the ovaries
   • Used when oral medications fail or in specific conditions
   • Success rates: 70-90% ovulation rate, 20-60% pregnancy rate per cycle
   • Higher risk of multiple pregnancy (10-30%) and ovarian hyperstimulation syndrome
   • Requires close monitoring with ultrasound and blood tests
4. Metformin: 
   • Insulin-sensitizing medication primarily used for PCOS with insulin resistance
   • May be used alone or in combination with clomiphene
   • Common side effects: Gastrointestinal symptoms (nausea, diarrhea)
5. Bromocriptine/Cabergoline: 
   • For hyperprolactinemia (elevated prolactin levels)
   • Restores ovulation in 80-90% of women with this condition

For Male Factor Infertility

1. Hormonal Treatments: 
   • Gonadotropins for hypogonadotropic hypogonadism
   • Antiestrogens (clomiphene, tamoxifen) in selected cases
2. Medications for Specific Conditions: 
   • Antibiotics for genital tract infections
   • Treatment of erectile dysfunction or ejaculatory problems
3. Antioxidant Supplements: 
   • Some evidence supports antioxidants (vitamin E, vitamin C, selenium, zinc) for improving sperm parameters, though results are mixed

Surgical Interventions

For Women

1. Hysteroscopy: 
   • Removal of uterine polyps, fibroids, or adhesions
   • Correction of uterine septum
   • Usually outpatient procedure with quick recovery
2. Laparoscopy: 
   • Treatment of endometriosis through ablation or excision of implants
   • Removal of ovarian cysts
   • Lysis of pelvic adhesions
   • Tubal surgery in selected cases
3. Tubal Surgery: 
   • Tuboplasty: Repair of damaged tubes
   • Fimbrioplasty: Opening of blocked fimbrial ends
   • Tubal reanastomosis: Reconnection of tubes after previous sterilization
   • Success rates vary widely based on the extent and location of damage
4. Laparoscopic Ovarian Drilling: 
   • For PCOS patients who don’t respond to medications
   • Creates small punctures in the ovary to reduce androgen production
   • Ovulation rates of 70-80% following the procedure

For Men

1. Varicocele Repair: 
   • Surgical correction of enlarged veins in the scrotum
   • Improves semen parameters in about 60-70% of men
   • Pregnancy rates of 30-50% following repair, though evidence is mixed
2. Surgical Sperm Retrieval: 
   • For men with obstructive azoospermia or ejaculatory dysfunction
   • Techniques include PESA (percutaneous epididymal sperm aspiration), MESA (microsurgical epididymal sperm aspiration), TESE (testicular sperm extraction)
   • Retrieved sperm are used with ICSI (intracytoplasmic sperm injection)
3. Correction of Ejaculatory Duct Obstruction: 
   • Transurethral resection of the ejaculatory ducts
   • Success rates of 50-75% for improving semen parameters

Assisted Reproductive Technologies (ART)

Intrauterine Insemination (IUI)

• Procedure: Specially prepared sperm are placed directly into the uterus around the time of ovulation
• Best for: Mild male factor infertility, cervical factor, unexplained infertility, some cases of ovulatory dysfunction
• Success rates: 10-20% per cycle, depending on age and diagnosis
• Often combined with: Ovulation induction medications to improve success
• Multiple pregnancy risk: 10-30% when combined with ovulation induction

In Vitro Fertilization (IVF)

• Procedure: Eggs are retrieved from the ovaries and fertilized with sperm in a laboratory, with resulting embryos transferred to the uterus 
• Steps involve: 
  • Ovarian stimulation with injectable medications (10-12 days)
  • Egg retrieval under sedation
  • Fertilization in the laboratory
  • Embryo culture for 3-5 days
  • Embryo transfer to the uterus
  • Luteal phase support with progesterone
• Best for: Tubal factor, severe male factor, diminished ovarian reserve, endometriosis, unexplained infertility after failed treatments 
• Variations: 
  • ICSI (Intracytoplasmic Sperm Injection): Single sperm injected directly into each egg
  • Assisted hatching: Thinning of embryo’s outer shell to aid implantation
  • PGT (Preimplantation Genetic Testing): Testing embryos for genetic abnormalities

Third-Party Reproduction

• Donor sperm: Used when male partner has severe male factor infertility or genetic concerns
• Donor eggs: Option for women with poor egg quality or quantity, typically due to advanced age or premature ovarian insufficiency
• Donor embryos: Created from donor eggs and sperm, or donated by couples who completed their families through IVF
• Gestational carrier (surrogate): Another woman carries the pregnancy when a woman cannot carry a pregnancy herself

The Emotional Impact of Infertility

Research shows that individuals with infertility experience significant psychological distress, with studies showing similar rates of anxiety and depression (as high as 60% in those undergoing fertility treatments) as those found in patients with cancer. This underscores just how emotionally challenging the infertility journey can be.

Common Emotional Responses

• Grief and sadness: Mourning the loss of a “normal” conception experience
• Anxiety and depression: Common responses to the challenges of infertility
• Stress and frustration: The constant cycle of hope and disappointment
• Relationship strain: Different coping styles, sexual pressure, financial stress
• Social isolation: Feeling disconnected from those who have not experienced infertility 
• Loss of control: Fertility treatments often leave couples feeling their lives are dictated by medical schedules

Coping Strategies

• Joining a Support Group: Support groups offer connection with others experiencing similar challenges.
• Seeking Professional Help: Mental health professionals specializing in infertility can provide valuable support.
• Practicing Self-Care: Activities that reduce stress have been shown to improve quality of life during treatment.
• Setting Boundaries: It’s reasonable to decline baby shower invitations or family gatherings if they trigger distress.
• Communicating with Your Partner: Open communication helps couples navigate the challenges together.
• Mindfulness and Relaxation Techniques: These can help manage stress during fertility treatment.

For Partners

Partners often experience significant distress but may show it differently:

• They may feel pressure to be “the strong one”
• May experience guilt, especially in male factor infertility
• May grieve differently or on a different timeline
• May struggle with how to best support their partner

Open communication, joint counseling sessions, and involvement in medical appointments can help partners navigate this challenge together.

The Financial Aspect of Infertility Treatment

The cost of infertility treatment can be substantial and is a significant concern for many couples:

Average Costs (United States)

• Initial consultation and testing: $1,500-4,000
• Medication costs per cycle:
  • Clomiphene: $100-500
  • Gonadotropins: $2,000-6,000
• IUI cycle: $500-2,500
• IVF cycle: $12,000-20,000
• Additional techniques (ICSI, PGT, frozen embryo transfer): $1,500-5,000 each

Insurance Coverage

Coverage varies widely:

• Some states have fertility insurance mandates requiring coverage of certain treatments
• Many employer-sponsored plans do not cover infertility or cover only diagnosis but not treatment
• Even with coverage, there may be significant out-of-pocket costs

Financial Resources

• Fertility clinic financing programs
• Specialized fertility treatment loans
• Grants and scholarships from nonprofit organizations
• Medication savings programs from pharmaceutical companies
• Income tax deductions for medical expenses

Making Decisions About Treatment

One of the most challenging aspects of infertility is deciding how far to go with treatment. Consider:

When to Try Another Cycle

Age is a significant factor; women over 40 may benefit from moving to more aggressive treatment sooner.

When to Consider a Different Approach

Consider changing approaches if:

• Multiple cycles have failed with the current approach
• Your diagnosis indicates a different treatment might be more successful
• Your emotional or financial resources for the current approach are depleted

When to Consider Taking a Break

Consider a break if:

• You’re experiencing significant emotional distress
• You need time to gather financial resources
• Major life events require your attention
• You need time to reconsider your family-building goals

When to Consider Alternative Family Building or Child-Free Living

For some, there comes a point when moving to alternatives makes sense:

• After multiple failed treatment cycles
• When medical advice suggests very low chances of success
• When the emotional, physical, or financial toll becomes too great

Options include:

• Adoption
• Foster parenting
• Living child-free
• Focusing on relationships with nieces, nephews, or other children in your life

Remember: It’s Not Your Fault

Perhaps the most important message in this entire article is that infertility is not your fault. It’s a medical condition, not a personal failing or punishment. You didn’t cause your infertility through past behaviors, thoughts, or actions.

Many patients blame themselves, thinking “If only I hadn’t waited so long” or “If only I had lived a healthier lifestyle.” While some lifestyle factors can impact fertility, many causes of infertility are beyond anyone’s control. Be kind to yourself throughout this process.

The Way Forward

Your fertility journey is uniquely yours. Some paths to parenthood are straightforward, while others take unexpected turns. As you navigate this journey:

• Be Your Own Advocate: Ask questions, seek second opinions if needed, and ensure you understand all your options.
• Recognize Your Limits: Decide how much treatment you’re willing to undergo, considering emotional, physical, and financial implications.
• Consider All Pathways: Remember that adoption, foster parenting, or living child-free are all valid choices.
• Take It One Step at a Time: Focus on the next appointment or decision rather than the entire journey ahead.

Infertility can feel all-consuming, but it doesn’t define you. With proper support, information, and care, many people facing infertility do eventually build their families—though sometimes in ways they hadn’t initially imagined.

Remember that you’re not alone, it’s not your fault, and there is support available every step of the way.

Sources

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Practice Committee of the American Society for Reproductive Medicine. (2020). Evidence-based treatments for couples with unexplained infertility: a guideline. Fertility and Sterility, 113(2), 305-322.

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