In general the average person normally has approximately 10 billion fat cells at birth. Research has shown that there are 2 periods in life in which fat cells are produced. This would include the third trimester of pregnancy and the time surrounding puberty. In general after these 2 periods of development the number of fat cells remains the same. A very infrequent exception to this role would be a patient who becomes morbidly obese. Because the number of fat cells normally remains stable after puberty subsequent weight gain and weight loss results from the fat cells becoming bigger and smaller. Because fat cells normally don’t reproduce new fat cells are not made after liposuction.