I was first told that my aorta is slightly dilated at 4.0 cm. There is some variation in the way the term aneurysm is used. For the thoracic aorta, most agree that at a diameter of 4.0 cm it has reached a size that is considered an aneurysm. The word dilated refers to the enlargement of the aorta.
Called also neonate and newborn. premature infant (preterm infant) one born before a gestational age of 37 completed weeks (259 days). The duration of gestation is measured from the first day of the last menstrual period and is expressed in completed days or weeks.
A premature birth is a birth that takes place more than three weeks before the baby is due. In other words, a premature birth is one that occurs before the start of the 37th week of pregnancy. Normally, a pregnancy usually lasts about 40 weeks. Premature birth gives the baby less time to develop in the womb. Premature babies, especially those born earliest, often have complicated medical problems.