The heartbeats of a mother and her unborn fetus synchronize when she breathes rhythmically. Researchers also found that a new born baby may benefit tremendously by co-sleeping with the mother to help time respiratory gas exchanges.
Scientists at the University of Aberdeen claim the connection paves the way for a new technique to detect development problems during pregnancy.
They said if this synchronization did not happen it could signal something might be wrong.
This, the researchers suggest, could allow early medical intervention.
Dr Marco Thiel, one of a team of physicists from the University of Aberdeen who worked on the study, said: "Pregnant mothers often report an awareness of a bond with their child.
"But until now there has been no hard evidence to suggest this bond is reflected in the interaction of their heartbeats.
"Our findings reveal that synchronization between the heartbeat of a mother and fetus does actually occur - but only when the mother is breathing in a rhythmical fashion.
"The fetus can sense the rhythmical shift in the mother's heartbeat and adapts its own heartbeat accordingly."
Dr Thiel added: "Importantly, the phenomenon does not occur when a mother is breathing normally.
After the baby is born, an intimate exchange of gases between mother and child is linked to healthy breathing patterns. They may suggest that co-sleeping could be the most effective way to consciously and unconsciously for a mother to monitor her newborn.
Researchers have discovered that the lining of a baby's nose is rich in receptors that may affect breathing.A mother's breath or smell stimulates some of these receptors and thus affects baby's breathing. One of the main gases in an exhaled breath is carbon dioxide, which acts as a respiratory stimulant. Researchers have recently measured the exhaled air coming from a mother's nose while sleeping with her baby. They confirmed this logical suspicion that the closer a baby is to its mother's nose, the higher the carbon dioxide concentration of the exhaled air, and the concentration of carbon dioxide between the face-to-face pair is possibly just the right amount to stimulate breathing.
The physiological effects of sleep-sharing are finally being studied in sleep laboratories that are set up to mimic, as much as possible, the home bedroom. Over the past few years, nearly a million dollars of government research money has been devoted to sleep-sharing research. These studies have all been done on mothers and infants ranging from two to five months in age. Here are the preliminary findings based on mother-infant pairs studied in the sleep-sharing arrangement versus the solitary-sleeping arrangement:
1. Sleep-sharing pairs showed more synchronous arousals than when sleeping separately. When one member of the pair stirred, coughed, or changed sleeping stages, the other member also changed, often without awakening.
2. Each member of the pair tended to often, but not always, be in the same stage of sleep for longer periods if they slept together.
3. Sleep-sharing babies spent less time in each cycle of deep sleep. Lest mothers worry they will get less deep sleep; preliminary studies showed that sleep-sharing mothers didn't get less total deep sleep.
4. Sleep-sharing infants aroused more often and spent more time breastfeeding than solitary sleepers, yet the sleep-sharing mothers did not report awakening more frequently.
5. Sleep-sharing infants tended to sleep more often on their backs or sides and less often on their tummies, a factor that could itself lower the SIDS risk.
6. A lot of mutual touch and interaction occurs between the sleep-sharers. What one does affects the nighttime behavior of the other.
Even though these studies are being conducted in sleep laboratories instead of the natural home environment, it's likely that within a few years enough mother-infant pairs will be studied to scientifically validate what insightful mothers have long known: something good and healthful occurs when mothers and babies share sleep.