It’s not just mums-to-be who should quit the booze before getting pregnant – men should also go teetotal prior to conception, a new study suggests.
Drinking alcohol three months before conception was associated with a 44% raised risk of congenital heart disease in babies when fathers did it, and 16% when mothers did it, compared to not drinking at all.
Congenital heart disease is a general term used to describe a range of birth defects that affect the way a baby’s heart works.
The research, published in the European Journal of Preventive Cardiology, also found binge-drinking prior to conception (having five or more drinks per sitting) was related to a 52% higher likelihood of these birth defects when men did it, compared to 16% for women.
“Binge-drinking by would-be parents is a high risk and dangerous behaviour that not only may increase the chance of their baby being born with a heart defect, but also greatly damages their own health,” said study author Dr Jiabi Qin, of Xiangya School of Public Health, in China.
Dr Qin said the results suggest that when couples are trying for a baby, men should not consume alcohol for “at least six months” before conceiving, while women should stop drinking one year before and avoid it while pregnant.
Congenital heart diseases are the most common birth defects, with approximately 1.35 million babies affected every year. These conditions can increase the likelihood of cardiovascular disease in later life, even after surgical treatment, and are the main cause of perinatal death.
Alcohol is a known teratogen – a factor which causes malformation of an embryo – and has been connected with foetal alcohol spectrum disorder (FASD). Around one in four children with FASD have congenital heart disease, indicating that alcohol might also be implicated in these disorders.
Previous studies investigating the link between alcohol and congenital heart disease have focused on prospective mothers, with inconclusive results. This is the first meta-analysis to examine the role of paternal alcohol drinking.
The researchers compiled the best data published between 1991 and 2019, which amounted to 55 studies including 41,747 babies with congenital heart disease and 297,587 without.
Dr Qin said: “We observed a gradually rising risk of congenital heart diseases as parental alcohol consumption increased. The relationship was not statistically significant at the lower quantities.”
Mums-to-be have also been warned about the dangers of drinking. The study found that compared to abstinence, maternal drinking was correlated to a 20% greater risk of tetralogy of Fallot, a combination of four abnormalities in the heart’s structure.
The authors said the observational study does not prove a causal effect, nor does it prove that paternal drinking is more harmful to the foetal heart than maternal drinking. The data cannot be used to define a cut-off of alcohol consumption that might be considered safe, they added.
“The underlying mechanisms connecting parental alcohol and congenital heart diseases are uncertain and warrant further research,” Dr Qin said.
“Although our analysis has limitations – for example the type of alcohol was not recorded – it does indicate that men and women planning a family should give up alcohol.”