Does A Man’s Age Matter In IVF? An Expert Explains The Impact On Sperm And Embryos

Having a baby later in life is becoming more common. While much of the discussion around fertility focuses on a woman’s biological clock, a man’s age can also influence the chances of conception and IVF success. 

Men continue to produce sperm throughout their lives, but this does not mean sperm quality remains unchanged. Ageing can affect sperm movement, DNA quality and the ability of an embryo to develop. A man’s age can affect IVF outcomes, particularly after 40 to 45 years, although the impact is generally smaller than that of a woman’s age. 

Can A Man’s Age Affect IVF Success?

“Yes, it can, though less than a woman’s age. Sperm quality slowly declines with age, especially after about 40 to 45,” says Dr Lavanya Kiran, Director and Lead Consultant, Obstetrics, Gynaecology, KIMS Hospitals, Electronic City, Bengaluru.

This decline may affect embryo development, pregnancy and live birth. It may also increase the risk of miscarriage. However, the evidence is mixed, and many men above 40 still become fathers through IVF.

A 2022 review published in Reproductive BioMedicine Online examined 28 studies involving 32,484 assisted reproductive technology cycles. It found that paternal age was associated with differences in clinical pregnancy, live birth, miscarriage and embryo development outcomes. The authors highlighted the need to consider the father's age alongside the mother's when planning a pregnancy.

However, a 2024 study published in the American Journal of Obstetrics and Gynaecology analysed 56,113 frozen embryo transfer cycles. It found no significant association between paternal age and live birth after adjustment for other factors when female partners were younger than 36. This shows why male age should be considered a risk factor, not a definite predictor of IVF failure.

How Does Ageing Affect Sperm DNA?

“Think of sperm as being made in a factory that keeps running for life but slowly gets worn out,” explains Dr Kiran.

Sperm are produced throughout a man's life. However, the cells responsible for making them keep dividing. Each round of cell division creates an opportunity for small DNA errors to occur.

Ageing can also affect the body's ability to repair damaged DNA. Oxidative stress, which occurs when harmful molecules called free radicals build up, can cause further damage to sperm cells.

This can lead to sperm DNA fragmentation. It refers to breaks or damage in the genetic material carried by sperm.

A sperm with DNA damage may still fertilise an egg. However, the resulting embryo may have difficulty developing or implanting. In some cases, it may stop growing, increasing the possibility of miscarriage.

What Other Changes Happen In Men As They Age?

“Male ageing can bring changes beyond DNA damage. These may include slightly lower semen volume, reduced sperm movement and changes in hormone levels,” says Dr Kiran.

Some men may also experience:

• Lower testosterone levels.
• A higher chance of genetic changes in sperm.
• Health conditions such as diabetes, high blood pressure and obesity that can affect fertility.
• Reduced sperm quality due to smoking, alcohol use and other lifestyle factors.

These changes do not affect every man in the same way. A semen analysis can help assess sperm count, movement and shape.

Does ICSI Overcome Age-Related Sperm Damage?

“ICSI helps when sperm count or movement is low, but it cannot identify or repair DNA damage inside the sperm,” explains Dr Kiran.

Intracytoplasmic sperm injection (ICSI) is an IVF technique in which a single sperm is injected directly into an egg. It can help overcome certain fertilisation problems, particularly when sperm count or motility is low.

However, selecting a sperm that looks healthy under a microscope does not guarantee that its DNA is undamaged. ICSI does not repair sperm DNA fragmentation. Therefore, it may not address every fertility problem linked to ageing.

Who Should Be More Careful About Male Age And IVF?

“Men above 40 to 45 should discuss their reproductive health with a fertility specialist, especially when their partner is also over 35,” says Dr Kiran.

A closer fertility assessment may be useful for:

• Men above 40 to 45 years.
• Couples where both partners are older.
• Men who smoke, drink heavily or are overweight.
• Men with diabetes or other conditions that can affect reproductive health.
• Couples with repeated IVF failure, poor embryo development or recurrent miscarriage.

Age alone does not mean a man will have fertility problems. A specialist should consider the couple's complete medical and reproductive history.

What Can Couples Do To Improve Sperm Health?

“Testing both partners is important. Couples should not assume that fertility problems are always related to the woman,” says Dr Kiran.

A semen analysis is often the first step in assessing male fertility. A specialist may also recommend a sperm DNA fragmentation test in selected cases, such as repeated IVF failure, recurrent pregnancy loss or poor embryo development. It is not automatically needed for every man above 40.

Other steps that may support sperm health include:

• Stop smoking and using tobacco.
• Limit alcohol and maintain a healthy weight.
• Exercise regularly and get adequate sleep.
• Eat a balanced diet with fruits, vegetables, nuts, pulses and whole grains.
• Keep medical conditions such as diabetes and hormonal problems under control.
• Avoid excessive heat exposure around the testicles.

Some fertility clinics may discuss sperm selection techniques or other laboratory options. However, evidence for these approaches varies. They are not suitable for every couple, and supplements should only be taken after medical advice.

When Should Couples See A Fertility Specialist?

“Couples should seek advice after 12 months of trying to conceive, or after six months if the woman is over 35. They should come sooner if there are known fertility concerns,” says Dr Kiran.

A consultation may also be useful if:

• The man is above 40 and the couple is planning a pregnancy.
• Either partner has a known reproductive health problem.
• The couple has experienced two or more miscarriages.
• IVF has failed more than once.
• The man has a history of testicular problems or difficulty with erection or ejaculation.

ALSO READ- IUI vs IVF: Two Experts Explains Differences and How to Decide

Conclusion

A man's age can influence IVF success through changes in sperm quality and DNA. The effect is usually smaller than that of a woman's age, and research findings are not consistent. Assessing both partners early, addressing health conditions and discussing suitable tests with a fertility specialist can help couples make informed decisions.