Having an excessively large newborn can create many complications during pregnancy, delivery and after delivery, a research by health experts at Kaiser Permanente Southern California revealed.

Researchers said women who are overweight or obese when they conceive are more likely to deliver excessively large babies, which increases health risks for mother as well as baby.

Lead researcher Dr. Mary Ellen Black said, "There are many complications that we associate with having an overly large infant during pregnancy, delivery and after delivery."

Excessively large babies face risks like shoulder injury and nerve damage during birth unless the mother opts for a c-section, which has its own surgical risks.

The researchers suggested that women who are planning to have a baby should shed excess weight before getting pregnant. Those who are already pregnant and overweight should contact their doctors to know how to keep weight gain within healthy limits.

The research, which carried out as a part of Kaiser's focus on the health effects of obesity, was published online this month in an American Diabetes Association journal called Diabetes Care.