Both men and women hoping to become parents should avoid drinking alcohol prior to conception to protect their baby against congenital heart defects, according to a new study published in the European Journal of Preventive Cardiology.
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 also examine the role of paternal alcohol drinking.
According to the findings, babies have a 44% increased risk of congenital heart disease when their father drank alcohol three months before conception, compared to babies whose dads did not drink. When the mothers drank during this time period or during the first trimester, babies had a 16% increased risk of disease.
The researchers suggest that when couples are trying for a baby, men should not consume alcohol for at least six months before conception while women should stop alcohol one year before and avoid it during pregnancy.
In addition, binge drinking — defined as five or more drinks per sitting — was related to a 52% higher likelihood of having a child with birth defects among men and 16% among 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, Central South University, Changsha, China.
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. The analysis showed a relationship between parental alcohol drinking and congenital heart diseases.
‘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,” said Qin.
The authors noted that this was an observational study and does not prove a causal effect, nor does it prove that paternal drinking is more harmful to the fetal heart than maternal drinking. The data cannot be used to define a cut-off of alcohol consumption that might be considered safe.
Regarding specific defects, the researchers 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 underlying mechanisms connecting parental alcohol and congenital heart diseases are uncertain and warrant further research. 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,” said Qin.
Alcohol is a known teratogen (causes malformation of an embryo) and has been connected with fetal alcohol spectrum disorder (FASD). Around one in four children with FASD have congenital heart disease.
Congenital heart diseases are the most common birth defects, with approximately 1.35 million infants affected every year. These conditions can increase the likelihood of cardiovascular disease later in life, even after surgical treatment, and are the main cause of perinatal death.
Source: European Society of Cardiology