An ectopic pregnancy may occur with the placenta attached to the peritoneum without involvement of the fallopian tube or ovary.

Features of an ectopic pregnancy within the abdominal cavity:

(1) The site of implantation is within the peritoneal cavity.

(2) It may present with abdominal pain and/or hemoperitoneum.

(3) Urine and serum beta-HCG are elevated.

(4) Ultrasonography identifies a gestational sac outside of the uterus.


The pregnancy is termed advanced if it greater than 20 weeks gestation.



(1) A viable infant may be delivered.

(2) It may be undiagnosed until late in the gestational period.

(3) It can occur in a woman who has had a hysterectomy.

(4) The placenta may be left in situ, at least initially.

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