In recent years, there has been a growing awareness of the significant role that male age plays in infertility and reproductive outcomes. While much attention has historically been focused on female fertility and age, research now indicates that advanced paternal age can also influence fertility potential and pregnancy outcomes.
In an interview with HT Lifestyle, Dr Parul Agarwal, Director ā Department of Fertility at Cloudnine Group of Hospitals in Noida, delved into the various aspects of male infertility associated with ageing and highlighted ā
1. Changes in Sexual Functions
Studies have consistently demonstrated that increasing male age is correlated with changes in sexual function, which can impact fertility. Diminished sexual functioning, including erectile dysfunction (ED), becomes more prevalent with age. Between the ages of 40 and 70, the probability of severe ED triples, while moderate ED doubles.
2. Spermatogenesis and Age
Spermatogenesis, the process by which spermatozoa are produced, is intricately regulated by hormonal factors. However, as men age, hormonal changes can adversely affect this process. The number of Sertoli cells which are very important for the spermatogenesis process, decreases with age, leading to reduced spermatozoa production. This decline in sperm quality can contribute to difficulties in achieving pregnancy.
3. Altered Semen Parameters
Advancing age also impacts semen quality. Age-related changes can result in lower sperm concentration (oligospermia), reduced sperm motility (asthenospermia), and abnormal sperm morphology (teratospermia). These alterations in semen parameters pose challenges for natural conception. However, decline in testosterone levels may also impact fertility through sexual dysfunction (low libido, erectile dysfunction, difficulty in achieving ejaculation). Men > 70 years old tend to have serum testosterone levels that are about one half to two thirds of those of men in their 20s.
4. DNA Fragmentation
Aging is associated with increased oxidative stress, which can lead to DNA damage in sperm cells. Studies indicate a higher rate of DNA fragmentation in sperm with advancing age. This can affect the genetic integrity of sperm and potentially impact embryo development and pregnancy outcomes.
5. Altered Testicular Volume
Testicular volume gradually decreases with age, particularly from around 60 years onwards. This decline is accompanied by higher levels of gonadotrophins and lower bioavailable testosterone, which can further impair fertility potential.
6. Medical Conditions and Environmental Factors
As men age, the risk of developing medical conditions increases, and exposure to environmental toxins also rises. Medical conditions requiring medications such as antihypertensives and antiandrogens can negatively impact sperm quality and fertility. Itās crucial for men experiencing infertility to undergo appropriate screening for these factors.
7. Hormonal Changes
Testosterone levels decline with age, a phenomenon known as andropause. This decline can lead to sexual dysfunction, including low libido, erectile dysfunction, and difficulty achieving ejaculation. Although spermatogenesis persists into old age, hormonal changes can still affect fertility outcomes.
8. Miscarriages
Advanced paternal age has been linked to an increased risk of first-trimester spontaneous abortions. The risk of spontaneous abortion rises significantly for paternal ages of 35 years and older, independent of maternal age. For paternal age ā„ 35 years, the risk of spontaneous abortion between 6 and 20 weeks of gestation was 1.27. This elevated risk was seen even when evaluating only those couples where the maternal age was < 30 years.
9. Assisted Reproductive Techniques
Advanced paternal age can impact the success of assisted reproductive techniques (ART). Lower fertilisation rates and compromised laboratory performance indicators have been observed with increasing male age, affecting outcomes such as blastocyst formation and embryo quality.