title: Assessing gestational age.
abstract: Decision making in obstetrics is based on accurate knowledge of fetal gestational age. Menstrual dating based on the last menstrual period is an accurate method for estimating gestational age. Other reliable indicators are fundal height, quickening, the date that the fundus reaches the umbilicus and the date that fetal heart tones are first auscultated. Combinations of these data approach the reliability of menstrual dating. Biochemical assays are useful in early pregnancy. Ultrasound is indispensable when the clinical situation is questionable.
mesh_terms: D006063:Chorionic Gonadotropin / Q000032:analysis; D005314:Embryonic and Fetal Development; D005260:Female; D005318:Fetal Heart; D005325:Fetal Organ Maturity; D005865:Gestational Age; D006339:Heart Rate; D006801:Humans; D008598:Menstruation; D011247:Pregnancy; D014463:Ultrasonography; D014599:Uterus / Q000033:anatomy & histology / Q000254:growth & development
chemical_list: D006063:Chorionic Gonadotropin