After spending approximately 40 weeks inside the womb, the average newborn weighs 7 1/2 pounds. Most babies weigh between 5 1/2 and 10 pounds. The average length of a newborn is 20 inches (50 centimeters), with a range of 18 to 22 inches. The average head circumference (the distance around the head) is 14 inches (35 centimeters).
Lactobacillus and Bifidobacterium are the most common probiotic bacteria. The Lactobacillus genus has 18 different bacteria strains, while the Bifidobacterium genus consists of eight strains.
The most common bacteria claimed to be a probiotic in the Bacillus genus is Bacillus subtilis. Bacillus subtilis is extremely common and is found mainly in soil, in either decomposing plant matter or dirt. You might even recognize subtilisâs cousin from the genus Bacillus.