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.
Types of premature birth. By definition, premature birth refers to birth before 37 weeks gestation, although most of the concern is focused on babies born before 34 weeks. Under the umbrella term of 'premature birth', there are three distinct scenarios. The first is women who go into labour before they should and give birth.