The link between pubertal onset & sperm quality
Is there a link between the timing of puberty and male reproductive health? Danish researchers from Rigshospitalet and EDMaRC believe so.
In new groundbreaking research scientists have found that the quality of semen is influenced by when males experienced puberty. This recently published study suggests that a fundamental marker for predicting male fertility could be the timing of pubertal onset.
What happens during male puberty?
The transition between childhood and adulthood is marked by a period known and puberty. During this time the body under goes changes to reach adult reproductive capacity. When puberty starts testicles begin to grow the scrotum becomes thinner and redder. This is followed by growth of the penis. Also, the larynx expands and vocal cords grow. Other changes include body hair development and growth spurts. Oil and sweat production increases.
All these changes are triggered and governed by hormonal signals. However, the age of which this all occurs is variable. Generally pubertal onset occurs between 9 and 14 years of age. This depends on many factors including epigenetic modifications, genetic variations, environmental and lifestyle influences.
Health risks linked to timing of pubertal onset
There has been a lot of interest in how the timing of puberty affects the body in adulthood. Consequently, researchers have looked at range of diseases and identified correlations with pubertal onset. Studies have found that early puberty increases the risk of obesity1, elevated blood pressure 2, 3, metabolic disorders and type 2 diabetes4, 5 in adulthood. Late onset of puberty is also not without risks, with psychosocial problems often identified6.
How does pubertal timing affect adult male fertility?
Until recently there has been little research into the timing of puberty and how it influences fertility during adulthood. This Danish study is the first of its kind. During the research, 1068 Danish men aged 19 participated. The men completed a questionnaire about their pubertal development. Also, they all provided blood and semen samples and had a medical examination.
In summary, results revealed that men who experienced late or early onset of puberty compared with their peers had smaller testicles and reduced semen quality at the age of 197. Men experiencing puberty earlier also had a higher BMI, they were shorter and were either smokers and/or exposed to prenatal tobacco smoke. Incidences of sexually transmitted diseases were also higher in men with earlier pubertal onset compared with normal timing.
What do these finding mean for young men?
It’s important to recognise that although this was a good sample size of participants there are so many factors that influence fertility. Hence, researchers concluded that puberty timing influences general health and disease risk. However, how strong this influence is difficult to determine.
Further research is necessary before drawing solid conclusions on the effects of pubertal timing on male fertility. In addition, if early or late puberty is detrimental to semen quality, there are ways to improve fertility. Overall, by focusing on clean living, good nutrition and regular exercise it is possible to improve semen quality.
- “Kindblom J. et al. (2006). Pubertal timing is an independent predictor of central adiposity in young adult males: the Gothenburg osteoporosis and obesity determinants study. Diabetes. Volume 55, Issue 11, (pp. 3047–52).” ↩
- “Hardy R, et al. (2006). Age at puberty and adult blood pressure and body size in a British birth cohort study. Journal of Hypertension. Volume 24, Issue 1 (59-66).” ↩
- “Hulanicka B, et.al. (2007). Relationship between early puberty and the risk of hypertension/overweight at age 50: evidence for a modified Barker hypothesis among Polish youth. Economics and Human Biology, Volume 5, Issue 1, (pp. 48-60).” ↩
- Widen, E. et.al (2012). Pubertal Timing and Growth Influences Cardiometabolic Risk Factors in Adult Males and Females. Diabetes Care. Volume 35, Issue 4, (pp. 850-6).” ↩
- “Prentice, P. et.al. (2013). Pubertal timing and adult obesity and cardiometabolic risk in woman and men: a systematic review and meta-analysis. International Journal of Obesity. Volume 37, (pp. 1036-43)”. ↩
- “Day, F. et al. (2015). Puberty timing associated with diabetes, cardiovascular disease and also diverse health outcomes in men and women: the UK BioBank Study. Science Report 5. 11208.”. ↩
- “Juul, A. et al. (2016). Self-reported onset of puberty and subsequent semen quality and reproductive hormones in healthy young men, Human Reproduction, doi: 10.1093/humrep/dew122, published online 6 June 2016.” ↩