Navigating the terminology in Neonatal Intensive Care Units (NICU) can be challenging for new parents and caregivers. Three essential terms—Estimated Gestational Age (EGA), Corrected Gestational Age (CGA), and Day of Life (DOL)—offer vital information on a baby’s growth timeline but often cause confusion. Estimated Gestational Age (EGA) refers to the age of the baby calculated from the first day of the mother's last menstrual period to the baby’s birth. For instance, a full-term baby is usually born at 40 weeks EGA. This measure helps healthcare providers understand how premature or full-term a baby was at birth. Corrected Gestational Age (CGA) adds the baby’s chronological age since birth to the EGA, providing a more accurate assessment of the baby’s current developmental stage. For example, if a baby was born at 30 weeks gestation and is now 4 weeks old, their CGA would be 34 weeks. CGA is particularly useful for premature infants, as developmental milestones are often judged based on CGA rather than actual age. Day of Life (DOL) simply tracks the number of days (or weeks) since birth. This count helps NICU staff monitor daily progress and care needs. For example, if a baby was born 4 days ago, their DOL is 4. Understanding the difference between these terms is important because they each provide distinct information: EGA tells us about the baby’s maturity at birth, CGA helps track ongoing development in relation to gestational age, and DOL focuses on postnatal age. Practice questions can help solidify these concepts. For instance, if Baby Lola was born at 30 weeks gestation and is now 4 weeks old, her EGA remains 30 weeks, her CGA is 34 weeks (30 + 4), and her DOL is 4 weeks. These calculations are integral to individualized care plans. For parents and caregivers, grasping these terms can ease communication with healthcare teams and better understand their infant’s progress. It also empowers them to participate actively in their baby’s care journey. If you find these NICU terms confusing, discussing them with your neonatologist or neonatal nurse can provide practical insights. Many hospitals offer educational resources to support families during this critical time. In sum, knowing what EGA, CGA, and DOL mean—and how they differ—helps everyone involved provide the best care and support for babies in the NICU.