The father’s role in producing a healthy baby doesn’t begin and end with conception.
Evidence is now pointing to an important link between the father’s health pre-conception and the health of their child over their lifetime.
“There’s this phenomenon called the developmental origins of health and disease where influences during early life, during pregnancy, during the early post-natal period change your metabolic set up for the rest of your life,” Dr Scott White, WA spokesman for the Royal Australian and New Zealand College of Obstetricians and Gynaecologists, said.
“Babies born after a period of inter-uterine hostility — where they are a bit smaller than they want to be, their placenta is not fantastic, they are a bit growth restricted — are at significantly increased risk for diabetes and heart disease and some cancers and all sorts of ‘badness’ in later life.
“Traditionally the effect of that was looked at from the maternal point of view and the fathers were pretty much ignored but more recent studies looking at the paternal contribution suggest there is a significant role for the health of the father prior to pregnancy and the health of the offspring.”
Perhaps the clearest association between a dad’s health and that of his offspring is seen in obesity, where it has been shown that paternal BMI is linked with the birth weight of baby boys and a correlation between a father’s “fatness” with a daughter’s increase in body fat from age five to nine has been identified.
Sperm carry not just DNA, but also signals known as non-coding RNA which can influence how development proceeds, according to scientists from the Robinson Research Institute, writing for The Conversation. These non-coding RNA are different in the sperm of obese men than in men of a healthy weight and, in some research in mice, have been shown to make their offspring fatter.
“There are significant epigenetic changes in the sperm of obese men so we know the healthier the father is, the better quality the sperm is, the better-quality embryo you make and that seems to have important lifelong impacts,” Dr White, who also provides preconception counselling at King Edward Memorial Hospital, said.
Alcohol, too, can be a catalyst for epigenetic changes that either switch on or off, or turn up or down, the expression of different genes that are carried both in the sperm and the egg, influencing the long-term health of offspring.
James Fitzpatrick, head of alcohol and pregnancy and FASD research at Telethon Kids Institute, said while Fetal Alcohol Spectrum Disorder could only be diagnosed if there had been direct exposure to the foetus by the woman’s drinking, some studies linked behavioural problems in children and adolescents with changes in the genetic expression of male sperm that are associated with alcohol exposure.
“It is not as hard and fast as the direct toxic effects of alcohol if the woman drinks, but there is the possibility these epigenetic effects that are passed on before the point of conception can modify later behavioural and indeed health outcomes,” Dr Fitzpatrick said.
It takes three months to make a mature sperm so any changes required to ensure a father is in peak condition for conception must be made well in advance, Dr White recommends. Just like prospective mothers, dads are advised to adopt a healthy lifestyle in the lead up to trying to conceive by maintaining a healthy weight, limiting alcohol intake to safe levels and not smoking or using illicit drugs.
Factors such as obesity and alcohol could reduce the number and quality of sperm, making it harder to get pregnant in the first place.
There’s also a role for dad’s-to-be to support their partner in staying on a healthy path during the nine months of pregnancy and beyond.
One of the biggest drivers of a woman drinking in pregnancy is her male partner drinking in pregnancy, according to Dr Fitzpatrick.
“That’s why it is very important that men support their partners not to drink in pregnancy and ideally that would be through taking a pregnant pause themselves or having the nine months off with their partner to support her during pregnancy.”