Editing Pregnancy test (section)

== Other uses ==
Pregnancy tests may be used to predict if a pregnancy is likely to continue or is abnormal. [[Miscarriage|Miscarriage, or spontaneous abortion or pregnancy loss]], is common in early pregnancy.<ref>{{Citation|chapter=Clinical presentation of ectopic pregnancy|date=26 January 1996|title=Ectopic Pregnancy|pages=14–20|publisher=Cambridge University Press|doi=10.1017/cbo9780511663475.002|isbn=978-0-521-49612-4}}</ref> Serial quantitative blood tests may be done, usually 48 hours apart, and interpreted based on the knowledge that hCG in a viable normal pregnancy rises rapidly in early pregnancy. For example, for a starting hCG level of 1,500 mIU/ml or less, the hCG of continuing, normal pregnancy will increase at least 49% in 48 hours. However, for pregnancies with a higher starting hCG, between 1,500 and 3,000&nbsp;mIU/ml, the hCG should rise at least 40%; for a starting hCG greater than 3,000 mIU/ml, the hCG should increase at least 33%.<ref name=":23">{{Cite journal|date=March 2018|title=ACOG Practice Bulletin No. 193: Tubal Ectopic Pregnancy|url=http://insights.ovid.com/crossref?an=00006250-201803000-00046|journal=Obstetrics & Gynecology|language=en|volume=131|issue=3|pages=e91–e103|doi=10.1097/AOG.0000000000002560|pmid=29470343|issn=0029-7844|author1=American College of Obstetricians Gynecologists' Committee on Practice Bulletins—Gynecology|s2cid=3466601}}</ref> Failure to rise by these minimums may indicate that the pregnancy is not normal, either as a [[Miscarriage|failed intrauterine pregnancy]] or a possible [[ectopic pregnancy]].<ref name=":23" />

[[Obstetric ultrasonography|Ultrasound]] is also a common tool for determining viability and location of a pregnancy. Serial ultrasound may be used to identify non-viable pregnancies, as pregnancies that do not grow in size or develop expected structural findings on repeated ultrasounds over a 1–2 week interval may be identified as abnormal.<ref name=":42">{{Cite journal|last1=Doubilet|first1=Peter M.|last2=Benson|first2=Carol B.|last3=Bourne|first3=Tom|last4=Blaivas|first4=Michael|date=10 October 2013|editor-last=Campion|editor-first=Edward W.|title=Diagnostic Criteria for Nonviable Pregnancy Early in the First Trimester|journal=New England Journal of Medicine|language=en|volume=369|issue=15|pages=1443–1451|doi=10.1056/NEJMra1302417|pmid=24106937|issn=0028-4793|url=https://escholarship.org/uc/item/3g86q83k}}</ref> Occasionally, a single ultrasound may be used to identify a pregnancy as non-viable; for example, an embryo that is greater than a certain size but that lacks a visible heart beat may be confidently determined to be not viable without the need for follow up ultrasound for confirmation.<ref name=":42" />