Placenta
Abnormal placentation
Ectopic pregnancy
Author: Mandolin S. Ziadie, M.D.
Last author update: 1 October 2011
Last staff update: 28 October 2020
Copyright: 2002-2023, PathologyOutlines.com, Inc.
PubMed Search: Ectopic pregnancy [title] placenta
Cite this page: Ziadie MS. Ectopic pregnancy. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/placentaectopicpreg.html. Accessed June 7th, 2023.
Definition / general
- Implantation of the embryo outside of the uterine cavity including within the tubes (90%), abdomen and the cornua of the uterus
- Occurs in 1/150 pregnancies
- Tubal pregnancies are the most common cause of hematosalpinx due to rupture which is a medical emergency and diagnosed with ultrasound, serum hCG and laparoscopy
- Bleeding is sometimes due to placental separation without rupture
Etiology
- 50% are associated with pelvic inflammatory disease or peritubal adhesions (due to appendicitis, endometriosis, surgery and leiomyomas)
Microscopic (histologic) description
- Though not extensively studied, reports indicate a high prevalence of placenta accreta and percreta, to which tubal rupture is attributed
- Placentas from abdominal pregnancies have been described as highly vascular with markedly diminished / absent decidua
