Advanced Age in Men CAN affect fertility
It has been widely accepted that physiological changes do occur in women over 35 years of age that can affect conception, pregnancy outcomes, and the health of the child. For men, their age is not as much of a factor when considering starting a family or even a factor in couples struggling with infertility.
A recent study reviewed over 40 years of research on advanced paternal age (APA) and it’s affect on fertility and various outcomes. There is no evidence based age group that describes APA. Most medical databases have arbitrarily made that cut off for men over 40 years of age. In this review, many of the articles looked at men over the age of 45, which has been on the rise, likely due to assisted reproductive techniques (ie. IUI, IVF).
Findings in men 45 and older:
decreased fertility
increased pregnancy complications (gestational diabetes, pre-eclampsia, and preterm labor
infants were found to have low APGAR scores, low birth weight, higher incidence of newborn seizures, and birth defects (congenital heart disease and cleft palate)
increased likelihood of children developing childhood cancers, psychiatric and cognitive disorders, and autism
According to the study, a natural decline in testosterone that occurs with aging can be a possible explanation to many of the findings above. These declining testosterone levels can have a large impact on sperm health.
A large meta-analysis of 90 studies including nearly 94,000 men showed that increasing male age negatively impacted semen volume, sperm concentration, count and motility, progressive motility, sperm quality and percentage of unfragmented cells (an increase in DNA fragmentation was seen in the older men).
Not only is age a possible factor in many of these outcomes, increasing age in men predispose them to a greater duration of exposure to disease, stress (physiologic and physiologic), negative lifestyle choices (ie. smoking), and genetic changes. All of which can also affect sperm health and quality.
Consistent studies have found decreased fertility in men of older age. Some of these studies did not account for female age, therefore some results have been conflicting. The best way to evaluate the effect of male’s age on pregnancy outcomes is with an oocyte donor, thus allowing age to be the dependent variable. Most studies done have other confounding variables (ie. procedures performed like ICSI), so again not providing the most accurate information.
The increased pregnancy risks when conception is successful is also very noteworthy. The health of both the sperm and egg can be passed to the offspring and become incorporated into the DNA of cells in the offspring’s body. This can possibly influence the pregnancy itself and the birth outcomes.
Miscarriage risks are not well understood in couples with advanced paternal age compared to advanced maternal age. This could be due to the limited studies, the confounding results, and the difficulty again accounting for the mother’s age. Therefore, this should not be interpreted as advanced paternal age having no effect on miscarriage rates.
In larger studies, preterm birth have been shown to be consistently linked to older paternal age, specifically >45 years of age.
The decline in sperm quality and increase in DNA fragmentation could contribute to the association of advancing paternal age and disorders in the offspring (ie cognitive disorders, autism). The risks are very small and again the methodologies behind most of these studies are inconsistent and do not provide consistent information. Consistent studies have found that children of older fathers are more likely to be diagnosed with schizophrenia, although this risk is very low.
Advanced paternal age is on the rise and more studies need to be done to address it’s possible effects on fertility health.
The title of the article is of great importance: Maternal, infant, and childhood risks associated with advanced paternal age: The need for comprehensive counselling for men. The need for education around paternal health and fertility is something still continually overlooked in many cases. Not only is the age of the male partner important when considering infertility cases, a full health work-up should be routinely assessed for BOTH partners. Conception is not the only factor to consider in fertility, it is the health of the pregnancy and the health of the child. More education surrounding the health of both partners before conception will likely result in better conception rates, healthier pregnancy outcomes and a positive impact on offspring.
In good health,
Dr. Kirti Deol