It's impossible to describe the sensation of baby kicking to someone who has never been pregnant. But now, new research out of the Imperial College London will at least allow you to explain just how strong those kicks are.
The study, published in the Journal of the Royal Society, is the first to quantify baby kicks in utero. By using a combination of MRI scans and computer models, it determined that the force of fetal kicks increases between 20 and 30 weeks, starting at 6.5 pounds of force and escalating to 10.5 pounds of force.
Researchers also found that skeletal stress caused by this force helps with bone and joint formation. So, like you probably already knew, those swift kicks are a sign of a growing, healthy baby.
Don't panic if you notice weaker kicks after that 30-week mark. At this point, researchers found kicks are reduced to about 3.8 pounds of force as baby begins to run out of room to move around. From 28 weeks on, doctors suggest doing kick counts to keep tabs on baby's normal activity. If you notice a major change in frequency, you should contact your OB.