Coffee if drunk in moderation offers no harm to an expectant mother, in terms of baby weight or gestational period, say researchers.
This study performed by researcher Dr Bodil Hammer Bech and team from the University of Aarhus in Denmark, and published online by the British Medical Journal.
The study took into account more than a thousand women, commencing before 20 weeks into their pregnancy.
The group was divided roughly equally, with the groups given decaffeinated and caffeinated coffee respectively. The members of each group were unaware of this.
In addition their drinks including colas were monitored to measure amounts of caffeine ingested.
The authors next measured the birth weights as well as lengths of pregnancy.
In retrospect the researchers found no significant observations that could support previous reports that link caffeine with low birth weight and shorter terms of pregnancy.
Previous studies have suggested caffeine might harm unborn babies, as it stays in the system longer in pregnant women, passing easily to a growing baby.
Health officials have warned that a high caffeine intake could affect birth weight or the chance of having a miscarriage.
In the study, the difference in average birth weight between babies of the two groups was a mere 16 g with the higher weight for the decaffeinated group. The lengths of pregnancy differing between the groups were an average of 2 days.
Says Bech who had previously done a study that positively linked high coffee consumption (more than 8 cups a day) and stillbirth, "About three cups of coffee a day is OK but women with a higher intake should be careful."
This is good news also for the British Coffee Association and their sentiments are conveyed by a spokesperson, "This new study is very interesting and supports the consistent advice given that pregnant women should stick to a safe upper limit - in line with guidance issued by the Food Standards Agency. This equates to three cups of brewed, or four cups of instant coffee.
"Coffee is one of the most heavily researched commodities in the world today and this adds to the wealth of scientific evidence which suggests that moderate coffee consumption is perfectly safe."