TY - CHAP M1 - Book, Section TI - Normal Pregnancy & Prenatal Care A1 - Bernstein, Helene B. A2 - DeCherney, Alan H. A2 - Nathan, Lauren A2 - Laufer, Neri A2 - Roman, Ashley S. PY - 2019 T2 - CURRENT Diagnosis & Treatment: Obstetrics & Gynecology, 12e AB - ESSENTIALS OF DIAGNOSISPregnancy is confirmed by the presence of amenorrhea and a positive pregnancy test.It is crucial to diagnose pregnancy as soon as possible to initiate appropriate prenatal care, avoid teratogen (an agent that causes a deleterious fetal effect) exposure, and diagnose nonviable or ectopic pregnancies. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/04/20 UR - obgyn.mhmedical.com/content.aspx?aid=1159952371 ER -