Bad news for men hoping to become dads: new research has found a potential link between paternal preconception drinking and a higher risk of birth defects.
And while those Friday night after work drinks are enticing, researchers found drinking as little as once per week could affect sperm, leading to a 35 per cent increase in the risk of abnormalities.
While the affects of a woman's drinking on foetal abnormalities is well known, the study, from Fudan University, China found they weren't the only group who may need to abstain in the lead up to conception.
They study assessed data on the drinking habits of more than 500,000 couples in China who had planned to conceive within a six month period between April, 2010-December, 2012. The man's drinking was then compared with birth defects reported in babies within a month of being born.
The risk was found to be 35 per cent higher among fathers who had drunk regularly - defined as at least once per week, with cleft palates found to be particularly higher among this group.
Other noteable abnormality risks included digestive tract issues, congenital heart disease and limb anomalies.
Researchers said the findings, published in the JAMA Pediatrics journal, showed that paternal alcohol consumption could affect sperm cells and recommended men too should abstain from drinking in the preconception period.
"Our finding suggests that future fathers should be encouraged to modify their alcohol intake before conceiving to reduce fetal risk, considering a paternal drinking rate of 31.2% substantially elevated the risk of birth defects," researchers said.
"Given the priority of preconception care, our study provides evidence for clinical recommendation and public health strategy making to improve offspring life quality."
It's not the first study to consider a possible link. Researchers from the University of California last year found mice born to males who had consumed alcohol for two to three weeks before mating with 'sober' female mice were at a higher risk of abnormalities.
Published in Alcoholism: Clinical and Experimental Research, researchers found mice born to fathers who had drunk 'displayed significant deficits' in brain development; interestingly, this was similar to that of the 'mouse model' of Fetal Alcohol Spectrum Disorders (FASD).
The 'atypical features' displayed by the baby mice included increased anxiety, hyperactivity and reduced motor function
"People have known about the dangers of maternal drinking during pregnancy for years; however, the safety of paternal drinking while trying to conceive has barely been considered," Science Daily quoted lead study author Kelly Huffman.
"Our research shows that fathers' exposure to alcohol leading up to conception can have deleterious effects on the child's brain and behavioral development."
"Fathers who consistently consume moderate to high amounts of alcohol leading up to conception may negatively impact offspring development due to the exposure to the paternal sperm," Huffman said.