• (incompetent cervix) A clinical diagnosis presenting with painless cervical dilatation and spontaneous mid-trimester birth in recurrent pregnancies in the absence of spontaneous membrane rupture, bleeding or clinical chorioamnionitis.
  NCI
  U.S. National Cancer Institute, 2021
• (incompetent cervix) Cervix that is abnormally prone to dilate without contractions in the second trimester of pregnancy, resulting in premature expulsion of the fetus.
  U.S. FDA Glossary
  U.S. Food & Drug Administration, 2021
• (cervical insufficiency) A cervix that shows a painless dilation and shortening during the second trimester of pregnancy with resultant recurrent pregnancy loss or delivery is considered incompetent [PMID:17490914, PMID:20643692]
  Human Phenotype Ontology (HPO)
  The Human Phenotype Ontology Project, 2025
• Incompetent UTERINE CERVIX is usually diagnosed in the second trimester of PREGNANCY. It is characterized by passive painless cervical dilation in the absence of UTERINE CONTRACTION; BLEEDING; INFECTION; and sometimes with the amniotic sac (AMNIOTIC MEMBRANE) bulging through the partially dilated cervix. Left untreated, this condition may lead to premature pregnancy loss, such as HABITUAL ABORTION.
  NLM Medical Subject Headings
  U.S. National Library of Medicine, 2025
• Cervical insufficiency (formerly called cervical incompetence) is painless cervical dilation resulting in delivery of a live fetus during the 2nd trimester. Transvaginal cervical ultrasonography during the 2nd trimester may help assess risk. Treatment is reinforcement of the cervical ring with suture material (cerclage).
  Merck Manuals
  Merck & Co., Inc., 2025
• Cervical insufficiency is defined by the American College of Obstetricians and Gynecologists (ACOG) as the inability of the uterine cervix to retain a pregnancy in the second trimester, in the absence of uterine contractions. It typically presents as acute, painless dilatation of the cervix, which can lead to a midtrimester pregnancy...
  Medscape
  WebMD, 2025
• An incompetent cervix, also called a cervical insufficiency, occurs when weak cervical tissue causes or contributes to premature birth or the loss of an otherwise healthy pregnancy.
  Mayo Clinic
  Mayo Foundation for Medical Education and Research, 2025