16-Pound Baby Boy Born in Texas Hospital

July 11, 2011— -- Everything really is bigger in Texas. On Friday, Janet Johnson gave birth to a baby boy, who entered the world weighing 16 pounds, more than double the average weight of a newborn.

Baby JaMichael was the heaviest baby to be born at Good Shepherd Hospital in Longview, and reportedly the largest newborn in the Lone Star State.

Johnson and her fiance, Michael Brown, knew that a big baby was coming soon. Two weeks before her Caesarean delivery, Dr. John Kirk, Johnson's obstetrician, said he expected the baby to weigh 12 or 13 pounds. But JaMichael even surprised the doctor.

"He was much larger than expected," said Kirk, explaining how JaMichael was the biggest baby he had ever delivered. "Both his mother and father are large people, and she was diagnosed with gestational diabetes, which contributed to the baby's size."

"They're calling him 'Moose' up here," JaMichael's father told ABC News' East Texas affiliate, KLTV.

"I'm just excited that he's here," said Johnson.

Johnson delivered her baby a week early. Kirk said delivery wasn't induced before that because the staff needed to wait for JaMichael's lungs to fully mature.

"While infants of diabetic mothers are large in size, their organ function is not more developed," said Dr. Manuel Porto, a professor and chairman of obstetrics and gynecology at University of California at Irvine. "In fact, their lung development may be delayed. Early delivery can lead to respiratory problems for the newborn."

According to the Guinness World Records, Ann Bates of Canada gave birth to the biggest newborn, in 1879, when her baby weighed in at a whopping 23 pounds, 12 ounces.

Experts said a woman's uterus can indeed handle 16 pounds of baby (think twins), but the baby's large size does not come without dangers.

A rare genetic disorder can cause abnormally large babies, but usually, a heavy baby is because of diabetes in the mother.

"A baby gets this large usually because a mother has poorly controlled diabetes and the baby is getting extra glucose calories during the pregnancy," said Dr. Ian Holzman, chief of newborn medicine at Mount Sinai School of Medicine in New York, N.Y.

Risks to the baby include birth trauma, said Holzman. This would include nerve damage to the arm, abdomen or injury to the head, as the doctor pulls the infant out if delivered vaginally.

"There is also a risk of low blood sugar in the baby after delivery because the baby's pancreas has been making extra insulin to deal with the extra sugar," said Holzman. "Once the sugar spigot is turned off the insulin causes the baby's blood sugar to drop."

Kirk said the hospital staff is currently trying to get the baby's blood sugar levels back up, but Kirk expects that baby and mother should be released from the hospital within two or three days. Kirk warned Johnson and Brown of the increased risks due to their baby's size, but he said he is optimistic, and happy to report that they are both doing well.

"He's really only had some minor problems," said Kirk. "We have made them aware of the possible complications down the road, but hopefully, they'll continue to be under medical care and we'll keep an eye on them."