For those planning to have a baby, it’s ideal that they refrain from alcohol consumption six to 12 months before conception to minimize the risk of an inborn heart anomaly.
This was the recommendation based on a Chinese study recently published in the European Journal of Preventive Cardiology, which showed that parental consumption of even moderate amounts of alcohol months before conception was linked to increased risk of congenital heart disease or CHD.
The study’s primary author, Dr. Jiabi Qin of the Xiangya School of Public Health, Central South University, Changsha, China, explained that drinking alcohol by either parent from three months before pregnancy up to the first three months of pregnancy was associated with a 44 percent higher risk of CHD for fathers and 16-percent risk for mothers, compared to not drinking at all.
Binge drinking
It was worse for binge drinking—defined as five or more drinks per session—and was associated with a 52 percent higher risk of CHD for men and 16 percent higher risk for women.
Previous studies have already suggested that alcohol drinking in expectant mothers could lead to CHD and other inborn defects, but this study shows that the risk for the baby is even higher if their would-be dads drank during the first trimester of pregnancy, or even months before the baby was conceived.
Dr. Qin advised that when couples are planning to have a baby, the men should stop drinking alcohol at least six months before fertilization, and the women should not drink alcohol, not even wine, one year before. The expectant mother should avoid alcohol totally during pregnancy.
The authors emphasized that a direct causal effect, especially of paternal drinking, could not be concluded in this study. It may be described as a strong observational finding, but it does not prove a causal effect.
It also cannot conclude that paternal drinking is more harmful to the fetal heart than maternal drinking, as the findings seem to show. It’s also difficult to define a cutoff of alcohol consumption that might be considered safe.
Perinatal deaths
“The underlying mechanisms connecting parental alcohol and CHD 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,” Dr. Qin clarified.
Every year, more than a million babies are born with CHD, frequently referred to as “blue babies,” because they look bluish because of poor oxygenation of their blood.
Due to their inborn defects, the circulation becomes faulty and instead of normally being oxygenated in the lungs, the blood may be shunted back to the circulation without being nourished with the much-needed fresh supply of oxygen.
Practically all of them will require delicate heart surgery to repair the defect. However, some cases may be so severe, they may not survive beyond a few days or weeks. CHD remains a major cause of perinatal deaths—dying within the first few days of delivery.
Fetal alcohol spectrum disorder
According to the study’s authors, alcohol is a known teratogen, or a cause of inborn anomalies. It has been associated with what has been labeled as fetal alcohol spectrum disorder (FASD), which has been reported in 2 to 5 percent of all pregnancies.
FASD is an array of disorders linked to alcohol consumption of the mother during pregnancy. This includes physical abnormalities like short height, low body weight, small head size.
Affected babies with FASD may also have poor coordination, low intelligence, poor hearing and eyesight, attention deficit hyperactivity disorder and various behavior problems. When they grow up, they have a higher tendency to have high-risk behaviors, including substance abuse. Around 20 to 25 percent of children with FASD have CHD.
The most common CHD which appeared to be associated with alcohol consumption in this study was tetralogy of Fallot or TOF, a combination of four abnormalities in the heart’s structure. These blue babies usually have shortness of breath and rapid breathing, especially during feeding or when they cry.
They may have loss of consciousness (fainting), clubbing appearance of fingers and toes, described as an abnormal, rounded shape of the nail bed. They have stunted physical development, and complain of easy fatigability, irritability and difficulty in sleeping. The characteristic murmurs are usually appreciated by the doctor when listening to the heart with the stethoscope, and modern tests such as the echocardiogram usually confirm the diagnosis.
Aside from alcohol intake of parents, TOF has also been associated with viral illness during pregnancy, such as German measles, poor nutrition before and during pregnancy, and mothers having their pregnancy older than 40 years of age.
In this latest analysis of various studies, Dr. Qin compiled all the high-quality data published between 1991 and 2019. This involved 55 studies including 41,747 babies with CHD and 297,587 without. The analysis indicated a dose-response relationship between parental alcohol drinking and CHD. The more the alcohol consumption of either parent, the higher the risk of CHD.
Dr. Qin said that they observed a gradually rising risk of CHD as parental alcohol consumption increased. However, he clarified that the relationship was not statistically significant at the lower quantities of alcohol taken. The risk signal is still there, so it’s best to avoid even small amounts of alcohol for would-be parents.