BACK TOTOP Browse A-ZSearchBrowse A-ZABCDEFGHIJKLMNOPQRSTUVWXYZ0-9 E-mail FormEmail ResultsName:Email address:Recipients Name:Recipients address:Message: Print-FriendlyBookmarksbookmarks-menuGestational ageFetal age - gestational age; Gestation; Neonatal gestational age; Newborn gestational ageGestation is the period of time between conception and birth. During this time, the baby grows and develops inside the mother's womb.Gestational age is the common term used during pregnancy to describe how far along the pregnancy is. It is measured in weeks, from the first day of the woman's last menstrual cycle to the current date. A normal pregnancy can range from 38 to 42 weeks.Infants born before 37 weeks are considered premature. Infants born after 42 weeks are considered postmature. Information Gestational age can be determined before or after birth.Before birth, your health care provider will use ultrasound to measure the size of the baby's head, abdomen, and thigh bone. This provides a view on how well the baby is growing in the womb. After birth, gestational age can be measured by looking at the baby's weight, length, head circumference, vital signs, reflexes, muscle tone, posture, and the condition of the skin and hair. Head circumferenceHead circumference is a measurement of a child's head around its largest area. It measures the distance from above the eyebrows and ears and around ...Read Article Now Book Mark Article If the baby's gestational age findings after birth match the calendar age, the baby is said to be appropriate for gestational age (AGA). AGA babies have lower rates of problems and death than babies that are small or large for their gestational age.The weight for full-term infants that are born AGA will most often be between 2,500 grams (about 5.5 lbs or 2.5 kg) and 4,000 grams (about 8.75 lbs or 4 kg).Infants weighing less are considered small for gestational age (SGA). Small for gestational age (SGA)Small for gestational age means that a fetus or an infant is smaller or less developed than normal for the baby's sex and gestational age. Gestation...Read Article Now Book Mark Article Infants weighing more are considered large for gestational age (LGA). Large for gestational age (LGA)Large for gestational age means that a fetus or infant is larger or more developed than normal for the baby's gestational age. Gestational age is th...Read Article Now Book Mark Article Open ReferencesReferencesBall JW, Dains JE, Flynn JA, Solomon BS, Stewart RW. Growth and nutrition. In: Ball JW, Dains JE, Flynn JA, Solomon BS, Stewart RW, eds. Siedel's Guide to Physical Examination. 9th ed. St Louis, MO: Elsevier; 2019:chap 8.Benson CB, Doubilet PM. Fetal measurements: normal and abnormal fetal growth and assessment of fetal well-being. In: Rumack CM, Levine D, eds. Diagnostic Ultrasound. 5th ed. Philadelphia, PA: Elsevier; 2018:chap 42.Graham GM, Park JS, Norwitz ER. Antepartum fetal assessment and therapy. In: Chestnut DH, Wong CA, Tsen LC, et al, eds. Chestnut's Obstetric Anesthesia: Principles and Practice. 6th ed. Philadelphia, PA: Elsevier; 2020:chap 6.Goyal NK. The newborn infant. In: Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 113.Nock ML, Olicker AL. Tables of normal values. In: Martin RJ, Fanaroff AA, Walsh MC, eds. Fanaroff and Martin's Neonatal-Perinatal Medicine. 11th ed. Philadelphia, PA: Elsevier; 2020:Appendix B, 2028-2066.Walker VP. Newborn evaluation. In: Gleason CA, Juul SE, eds. Avery's Diseases of the Newborn. 10th ed. Philadelphia, PA: Elsevier; 2018:chap 25.AllVideoImagesTogRelated Information Review Date: 12/10/2021 Reviewed By: Neil K. Kaneshiro, MD, MHA, Clinical Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- © 1997- All rights reserved. A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.Content is best viewed in IE9 or above, Firefox and Google Chrome browser.