WOMEN have been increasingly delaying the start of motherhood. This is related to a greater entry of women into the labour market, increase in life expectancy and use of contraception. Women now also have increased access to assisted reproductive techniques which facilitates fertility in older couples. This has resulted in discussions and research into the effects of advanced maternal age on fertility, pregnancy complications, birth anomalies, and poorer outcomes of the offspring.

It is generally accepted that maternal age is the main limiting factor in fertility and good reproductive outcome. However, is there an impact of male age on fertility and reproductive outcome? This is an area that has received little attention.

There has been a historical fascination with advanced male age and paternity. The father of Noah (Methusalem) fathered his son, Lamech at age 187 years. Genesis 5: 25-26 report that Methusalem lived 782 years and had other sons and daughters. More recent scientific publications report the oldest age of paternity at 94 years.

Are men delaying fatherhood?

Men are delaying fatherhood. In Germany, the age of married fathers increased from 31 years in 1991 to 33 years in 1999. In the United Kingdom in 1993, 25 per cent of live births were to fathers between the ages of 35 and 54 years. This increased to 40 per cent in 2003.

What is the peak age for male fertility?

Fertility rates are at their peak in men at age 24 years. Potential for sperm production continues to exist for life in men, as opposed to women where there is cessation in function of the ovaries with menopause. However in men, despite the continued reproductive potential with increasing age, there is a detrimental effect of advancing male age on reproductive organs and tissue.

What are the changes in male reproductive tissue with increasing age?

Testicular size (volume) reduces towards the eighth decade of a man’s life with the size approximately one-thirds the testicular size of a man between the ages of 18 and 40 years. This reduction is size is accompanied by reduction in cell number and function. Starting at age 30 years, testicular cells producing the male hormone testosterone also reduce in function and this may affect erectile function. Sexual dysfunction is common in older men and this may lead to infertility. Sperm volume and motility also reduce with increasing age. Male reproductive hormones also change with increasing age.

Is advanced paternal age associated with Down’s syndrome?

The influence of paternal age and Down’s syndrome is controversial. Most studies have not shown an association between advanced paternal age and chromosomal abnormalities including Down’s syndrome.

Are women likely to have spontaneous abortions if the male partner is over 40 years?

Rates of spontaneous abortions are twice as high in men over 45 years compared to those less than 25 years. This risk is particularly relevant if the maternal age is over 30 years.

Which medical conditions have been linked to advanced paternal age?

Several medical conditions related to genetic defects have been associated with advanced paternal age. These include achondroplasia which may lead to dwarfism, and Marfan syndrome. Conditions such as schizophrenia, autism and bipolar disorder have been shown in studies to be associated with advanced paternal age.

Advanced male age is associated with reproductive hazards. However, with the use of assisted reproductive techniques, many of these obstacles may be circumvented.

Dr Belinda Morrison is a consultant urologist and lecturer at the University of the West Indies and Mona Institute of Medical Sciences, Mona, Kingston 6. Please send questions and comments to: belinda.morrison02@uwimona.edu.jm.