Secondary Infertility

Secondary infertility means having difficulty getting pregnant or causing a pregnancy after previously having a child without fertility treatment. It can affect men, women, or both partners, and it is more common than many people realize. In men’s health, secondary infertility often raises questions about sperm count, sperm motility, hormone changes, age, lifestyle, and whether something has changed since the last successful pregnancy. The good news is that it is a real medical issue with identifiable causes, useful testing, and treatment options in many cases.

Secondary infertility at a glance
What is secondary infertility?
Why secondary infertility matters
What secondary infertility means in men’s health
Causes of secondary infertility
Signs and symptoms
What’s normal vs what’s not?
Diagnosis and fertility testing
What abnormal results can mean
Treatment options
Lifestyle changes that may help
Common myths and misconceptions
Questions to ask your doctor
Related tests and terms
Frequently asked questions
References

Secondary infertility at a glance

Secondary infertility is the inability to conceive or carry a pregnancy after a previous successful pregnancy.
It can involve male factors, female factors, both partners, or unexplained causes.
Male-factor infertility contributes to a substantial share of infertility cases, which is why a semen analysis is often one of the first tests recommended by fertility experts and organizations such as the American Society for Reproductive Medicine.
Common male causes include lower sperm count, poor sperm motility, abnormal sperm morphology, hormonal problems, varicocele, erectile or ejaculation problems, and lifestyle or environmental exposures.
Age can matter for both partners. Male fertility does not stop abruptly, but sperm quality and reproductive outcomes can change over time, as discussed in research on paternal age and reproductive health.
Secondary infertility is not always permanent. Many cases are treatable or manageable.
Evaluation usually includes history, physical exam, semen testing, and sometimes hormone tests, imaging, or genetic workup.
If pregnancy has not happened after 12 months of regular unprotected sex, or after 6 months when the female partner is 35 or older, a medical evaluation is generally recommended by sources such as the Mayo Clinic.

What is secondary infertility?

Secondary infertility is a fertility problem diagnosed when a couple has difficulty conceiving again after previously conceiving naturally or with little difficulty. Some definitions also include difficulty carrying a pregnancy to live birth after a prior successful pregnancy. In practical terms, people usually use the term when they had one child before and are now struggling to have another.

For many couples, secondary infertility is especially confusing. A prior pregnancy can create the expectation that fertility should still be intact. But fertility is not fixed. Sperm parameters, ovulation, fallopian tube function, uterine health, sexual function, hormones, medical conditions, and age can all change between pregnancies.

Secondary infertility is different from primary infertility, which refers to never having achieved a pregnancy before.

Secondary infertility vs primary infertility

Primary infertility: No previous pregnancy has occurred.
Secondary infertility: A previous pregnancy has occurred, but conception or successful pregnancy is now difficult.

From a medical standpoint, both deserve a full evaluation. A previous pregnancy does not rule out male-factor infertility, and it does not guarantee that the current problem is female-related.

Why secondary infertility matters

Secondary infertility matters medically, emotionally, and practically. It can delay family planning, create stress within relationships, and lead people to overlook symptoms that deserve attention. Sometimes it is the first clue to an underlying health issue such as low testosterone from pituitary disease, a varicocele, obesity-related hormone disruption, diabetes, thyroid disease, sexually transmitted infection, or damage from heat, toxins, or medications.

It is also common for couples to wait longer than they should before getting checked because they assume, “We’ve done it before, so it will happen again.” That delay can matter. Some fertility problems are easier to treat earlier.

Professional guidance from groups such as the American Society for Reproductive Medicine and patient resources from the NHS emphasize that infertility evaluation should include both partners.

What secondary infertility means in men’s health

In men’s health, secondary infertility means a man who has previously fathered a pregnancy may now have reduced fertility potential. That change may happen even if sex drive feels normal and erections are still adequate. Fertility is not determined by libido alone. A man can feel completely healthy and still have changes in sperm concentration, motility, morphology, DNA integrity, ejaculation, or hormone balance.

Male fertility can be affected by:

New varicocele or worsening varicocele
Weight gain or metabolic disease
Low or high hormone levels
Testicular injury or infection
Use of testosterone or anabolic steroids
Smoking, heavy alcohol use, cannabis, or other drugs
Exposure to heat, solvents, pesticides, or radiation
Stress, sleep issues, or chronic illness
Age-related sperm changes

The World Health Organization laboratory manual for semen examination and male infertility reviews in peer-reviewed literature both note that semen quality can vary over time, which is why repeat testing is often used.

Causes of secondary infertility

Secondary infertility can result from one factor or a combination of factors. It is often divided into male causes, female causes, combined causes, and unexplained infertility.

Male causes of secondary infertility

Low sperm count: Fewer sperm in the ejaculate can reduce the chances of fertilization.
Poor sperm motility: Sperm may not swim effectively enough to reach the egg.
Abnormal sperm morphology: A higher share of sperm may have abnormal shape, which can be associated with reduced fertility.
Varicocele: Enlarged veins in the scrotum can impair sperm production and function. Varicocele is a common, potentially treatable cause of male infertility according to the Merck Manual.
Hormonal disorders: Problems involving testosterone, follicle-stimulating hormone, luteinizing hormone, prolactin, or thyroid hormones can affect sperm production.
Testicular damage: Infection, trauma, undescended testis history, surgery, radiation, or chemotherapy can impair fertility.
Ejaculation disorders: Retrograde ejaculation, delayed ejaculation, or anejaculation can interfere with conception.
Erectile dysfunction: If intercourse is not happening consistently during the fertile window, pregnancy becomes less likely.
Genetic factors: Some men have chromosomal or microdeletion-related causes that may become more relevant once fertility is evaluated.
Testosterone use: External testosterone can suppress sperm production, sometimes significantly. This is well recognized by fertility specialists and summarized in literature on exogenous testosterone and spermatogenesis.

Female causes of secondary infertility

Age-related decline in egg quantity and quality
Ovulation disorders, including polycystic ovary syndrome
Blocked or damaged fallopian tubes
Endometriosis
Fibroids or uterine abnormalities
Pregnancy-related complications that affected the uterus or tubes
Hormonal disorders such as thyroid disease or elevated prolactin

Combined or shared factors

Age of both partners
Timing of intercourse outside the fertile window
Relationship stress or sexual dysfunction
Changes in weight, exercise extremes, or sleep
Smoking, alcohol, drug use, and environmental exposures

Unexplained secondary infertility

Sometimes standard testing looks normal in both partners, yet pregnancy still does not occur. This is often called unexplained infertility. It does not mean nothing is wrong. It means current tests have not identified a clear cause.

Signs and symptoms

The main sign of secondary infertility is straightforward: pregnancy is not happening despite regular unprotected sex after a previous successful pregnancy. Unlike many medical conditions, infertility often has no obvious symptoms, especially on the male side.

Still, certain clues can point toward a male-factor issue:

Reduced semen volume
Difficulty with erections or ejaculation
Lower sex drive
Testicular pain, swelling, heaviness, or visible veins in the scrotum
History of mumps orchitis, sexually transmitted infection, or genital surgery
Breast enlargement, decreased shaving frequency, or other signs of hormone imbalance
Use of testosterone, anabolic steroids, finasteride, or certain other medications

Many men with abnormal semen results have none of these symptoms. That is why semen analysis is so important.

What’s normal vs what’s not?

There is no single “fertility score” that perfectly predicts whether pregnancy will happen. Fertility exists on a spectrum. A man can have semen values below reference limits and still conceive, while someone with values in the normal range may still face infertility.

That said, semen analysis reference ranges are useful starting points. The WHO semen manual is commonly used to interpret results.

Common semen analysis benchmarks

Semen volume: Lower volume may suggest incomplete collection, obstruction, low androgen effect, or retrograde ejaculation.
Sperm concentration: Lower concentration means fewer sperm per milliliter.
Total sperm number: Reflects the overall sperm output in the sample.
Motility: Measures how well sperm move.
Morphology: Describes sperm shape using strict criteria.

Reference-style semen analysis table

These values are general WHO-style lower reference limits and must be interpreted in clinical context.

Semen volume: about 1.4 mL or higher
Sperm concentration: about 16 million/mL or higher
Total motility: about 42% or higher
Progressive motility: about 30% or higher
Normal morphology: about 4% or higher by strict criteria

Reference values can vary slightly by laboratory and guideline edition. A single abnormal result usually needs confirmation with repeat testing because semen parameters naturally fluctuate.

Normal fertility timing vs possible infertility

Usually considered within expected range: Pregnancy occurs within 12 months of regular unprotected sex when the female partner is under 35.
Worth evaluation: No pregnancy after 12 months, or after 6 months if the female partner is 35 or older.
Seek earlier assessment: Known male-factor issues, irregular cycles, pelvic disease, prior chemotherapy, testosterone use, or sexual dysfunction.

Diagnosis and fertility testing

A secondary infertility workup should assess both partners. For men, evaluation usually starts with a reproductive history, medication review, physical exam, and semen analysis.

What testing often includes for men

Medical and fertility history
Doctors ask about previous pregnancies, timing of infertility, intercourse frequency, erectile function, ejaculation, fevers, surgeries, infections, medications, supplements, testosterone use, and occupational exposures.
Physical exam
This may assess testicular size, varicocele, signs of hormone imbalance, and anatomy of the penis and scrotum.
Semen analysis
This is the core male fertility test. It measures semen volume, sperm concentration, total count, motility, and morphology. Because sperm production takes around 2 to 3 months, repeat testing is often done to confirm a pattern.
Hormone testing
Common labs may include total testosterone, follicle-stimulating hormone, luteinizing hormone, prolactin, estradiol, and thyroid testing when indicated.
Scrotal ultrasound
Used when varicocele, structural issues, or testicular abnormalities are suspected.
Post-ejaculatory urinalysis
May help assess retrograde ejaculation in selected cases.
Genetic testing
Recommended in some men with severe oligospermia or azoospermia.
Sperm DNA fragmentation testing
Not routine for everyone, but it may be considered in recurrent pregnancy loss, recurrent IVF failure, or certain male risk factors. Use is individualized.

Common fertility tests and what they assess

Semen analysis: Basic sperm health and semen quality
Hormone panel: Signals from the brain and testes that regulate sperm production
Scrotal ultrasound: Varicocele or structural problems
Genetic tests: Chromosomal or Y chromosome causes
Female partner testing: Ovulation, ovarian reserve, tubal patency, uterine evaluation

The StatPearls review on male infertility and guidance from professional fertility societies support this stepwise approach.

What abnormal results can mean

Abnormal fertility test results do not automatically mean a man cannot father a child. They help identify where the problem may lie and what treatment path makes the most sense.

Examples of abnormal male findings

Low sperm concentration: May suggest impaired production, hormone issues, varicocele, toxins, or suppression from testosterone use.
Low motility: May reduce the chance that sperm can travel through cervical mucus and the reproductive tract.
Abnormal morphology: Can be associated with reduced fertilization potential, though it must be interpreted carefully and not in isolation.
Azoospermia: No sperm seen in the ejaculate. This may result from obstruction or severely impaired sperm production and needs specialist evaluation.
Low semen volume: Could suggest incomplete sample collection, obstruction, low seminal vesicle contribution, androgen deficiency, or retrograde ejaculation.
Abnormal hormones: High follicle-stimulating hormone can suggest impaired testicular sperm production, while low gonadotropins can point toward hypothalamic or pituitary causes.

Comparison of possible male causes and clues

Varicocele
Possible clues: dull ache, scrotal heaviness, abnormal semen analysis
Exogenous testosterone use
Possible clues: history of TRT or anabolic steroids, very low sperm count
Hormonal disorder
Possible clues: low libido, low energy, abnormal testosterone or gonadotropins
Obstruction
Possible clues: low semen volume, azoospermia, prior vasectomy or surgery
Genetic cause
Possible clues: severe oligospermia or azoospermia
Lifestyle or heat exposure
Possible clues: recent illness, sauna or hot tub use, smoking, obesity, toxin exposure

Because fertility is multifactorial, these findings are best interpreted by a clinician with experience in male reproductive health.

Treatment options

Treatment for secondary infertility depends on the cause. In many cases, improving sperm health, correcting reversible problems, or using fertility treatment can meaningfully increase the chance of pregnancy.

Medical treatment options for men

Stopping testosterone therapy or anabolic steroids: This is often a crucial first step when sperm production has been suppressed. Recovery may take months and should be supervised.
Treating hormone disorders: Selected men may benefit from treatment directed at prolactin disorders, thyroid disease, or hypogonadotropic hypogonadism.
Varicocele repair: In some men with a palpable varicocele and abnormal semen results, surgery may improve semen parameters and fertility potential.
Treatment of infection or inflammation: Used when there is a specific diagnosis, though antibiotics are not a blanket treatment for infertility.
Management of erectile or ejaculation problems: Sexual function treatment may improve the ability to conceive naturally.

Assisted reproductive technology

Intrauterine insemination (IUI): Washed sperm are placed into the uterus around ovulation.
In vitro fertilization (IVF): Eggs are fertilized outside the body.
Intracytoplasmic sperm injection (ICSI): A single sperm is injected into an egg. This is commonly used in significant male-factor infertility.
Surgical sperm retrieval: May be used when no sperm appear in the ejaculate but sperm can be obtained directly from the testicle or epididymis.

When treatment focuses on both partners

It is common for couples to have more than one issue at the same time. For example, mild male-factor infertility plus reduced ovarian reserve may change the ideal treatment plan. Fertility care works best when both partners are evaluated together.

Lifestyle changes that may help

Lifestyle changes are not a guaranteed fix, but they can improve overall reproductive health and may help some men with secondary infertility, especially when poor sleep, obesity, smoking, excess alcohol, or heat exposure are contributing.

Steps that may support sperm health

Stop smoking
Smoking is associated with poorer semen quality and increased oxidative stress.
Limit alcohol
Heavy alcohol use may impair hormones and sperm production.
Avoid anabolic steroids and do not self-prescribe testosterone
External testosterone can sharply reduce sperm production.
Optimize weight
Obesity is associated with hormonal changes and poorer fertility outcomes.
Improve sleep and manage stress
Poor sleep and chronic stress may affect hormones, sexual function, and general health.
Reduce heat exposure
Frequent hot tubs, saunas, and some occupational heat exposures may worsen semen quality in some men.
Review medications and supplements with a clinician
Some drugs can affect ejaculation, hormones, or sperm production.
Exercise regularly, but avoid extremes
Moderate activity supports metabolic health, while overtraining may sometimes disrupt hormones.

If you are trying to conceive, it is reasonable to treat fertility like an overall health signal rather than only a sperm issue.

Common myths and misconceptions

Myth 1: If you already have a child, infertility cannot be the problem

False. Secondary infertility is real, and fertility can change over time for either partner.

Myth 2: If sex drive is normal, sperm must be normal

False. Libido and fertility are not the same thing. A man can have normal sexual function and abnormal semen results.

Myth 3: Secondary infertility is usually the woman’s issue

False. Male factors are common in infertility, either alone or together with female factors. That is why both partners should be evaluated.

Myth 4: One abnormal semen analysis means permanent infertility

False. Semen results fluctuate. Repeat testing and broader evaluation are often needed.

Myth 5: Testosterone therapy helps fertility because it raises testosterone

False. External testosterone often suppresses sperm production rather than improving it.

Questions to ask your doctor

Could male-factor infertility be contributing to our difficulty conceiving?
Do I need a semen analysis, and should it be repeated?
Should I have hormone testing?
Could a varicocele, medication, or testosterone use be affecting fertility?
What lifestyle factors are most relevant in my case?
Should my partner and I be evaluated at the same time?
At what point should we consider IUI, IVF, or ICSI?
Are there signs that suggest a genetic issue or obstruction?
Would seeing a reproductive urologist make sense?

Semen analysis: The main laboratory test used to assess sperm and semen quality.
Oligospermia: Low sperm concentration.
Azoospermia: No sperm in the ejaculate.
Asthenozoospermia: Reduced sperm motility.
Teratozoospermia: Increased abnormal sperm morphology.
Varicocele: Enlarged veins in the scrotum that may affect sperm production.
Hypogonadism: A condition involving low testosterone or impaired testicular hormone function, with many possible causes.
Sperm DNA fragmentation: A specialized measure of sperm DNA damage, sometimes used in selected infertility cases.
IUI, IVF, and ICSI: Fertility treatments used depending on the cause and severity of infertility.

Frequently asked questions

Can a man have secondary infertility even if he fathered a child before?

Yes. A previous pregnancy does not guarantee current fertility. Sperm quality, hormones, medical conditions, and lifestyle factors can change over time.

How common is secondary infertility?

It is common enough that fertility clinics see it regularly. Exact numbers vary by population and definition, but it is a well-recognized reproductive health issue.

How long should we try before seeing a doctor?

Generally, after 12 months of regular unprotected sex if the female partner is under 35, or after 6 months if she is 35 or older. Earlier evaluation makes sense if there are known fertility risk factors.

Does age affect male secondary infertility?

Yes. Male fertility does not end suddenly, but increasing paternal age can affect semen quality and some reproductive outcomes, according to published research on paternal age.

Can stress cause secondary infertility?

Stress alone is rarely the whole explanation, but it can affect sleep, sexual function, hormone balance, and relationship dynamics. It may contribute, even if it is not the sole cause.

Can testosterone replacement therapy cause secondary infertility?

Yes. External testosterone can suppress the hormones needed for sperm production. Men trying to conceive should discuss alternatives with a qualified clinician.

Is secondary infertility treatable?

Often, yes. Treatment depends on the cause and may include lifestyle changes, medication adjustments, treatment of hormone problems, varicocele repair, or assisted reproductive techniques.

What is the first test for male secondary infertility?

Usually a semen analysis, paired with a history and physical exam. Depending on the results, hormone testing and imaging may follow.

Can you have normal semen analysis results and still be infertile?

Yes. Standard semen testing does not capture every aspect of sperm function, timing, egg quality, tubal function, or implantation. Normal results do not rule out fertility problems.

When should we see a reproductive urologist?

If semen analysis is abnormal, there is a history of testosterone use, varicocele, erectile or ejaculation issues, testicular symptoms, or prior genital surgery, a reproductive urologist can be especially helpful.