The usefulness of gestational sac and placental sonographic morphology in differentiating between second‐trimester tubal and abdominal pregnancy: Case report and a review of literature

Abstract

Second-trimester tubal pregnancy is rarely encountered and published cases are limited. There are no established sonographic criteria to differentiate it from abdominal pregnancy; however, differences in their medical management make this distinction important. We report a case of a 14-week 5-day tubal pregnancy that presented near rupture. Sonography demonstrated many overlapping features with abdominal pregnancy. In addition, the extrauterine gestational sac was rounded and well defined and the placenta was crescent-shaped. We propose that these sonographic features represent a second-trimester tubal pregnancy rather than an abdominal pregnancy.

Imaging Unusual Pregnancy Implantations: Rare Ectopic Pregnancies and More

“…Ultrasound findings seen in abdominal ectopic pregnancies include the absence of myometrial tissue continuing from the uterus around the gestational sac, abnormal placentation, oligohydramnios, and unusual fetal lie [42]. A misshapen gestational sac and flattened placenta may help distinguish an abdominal ectopic from a late-presenting tubal ectopic pregnancy, which is more likely to show a rounded gestational sac and crescentic placenta [44]. Careful sonographic evaluation of the myometrium can also help distinguish a late-presenting abdominal ectopic pregnancy from an intrauterine gestation.…”

Ruptured Tubal Ectopic Pregnancy at Fifteen Weeks Gestational Age

“…Typical ultrasound features used to diagnose ectopic pregnancies in the first trimester include the presence of a pseudo-gestational sac, thickened endometrium, fluid in the posterior cul-de-sac and the tubal ring sign. The tubal ring sign is the most specific finding for a tubal ectopic pregnancy but may become less reliable as the pregnancy advances and the tubal wall thins 3…”

“…Ninety-five percent of ectopic pregnancies occur in the fallopian tubes, and these are most often discovered in the first trimester. There are only a handful of cases of second-trimester tubal ectopic pregnancies published in the literature 3. Most ectopic pregnancies are diagnosed between six and nine weeks of gestation when the patient becomes symptomatic 1.…”

“…Most ectopic pregnancies are diagnosed between six and nine weeks of gestation when the patient becomes symptomatic 1. They often present with complaints of vaginal bleeding, pelvic pain and occasionally syncope 3. Tubal rupture is common with as many as 16% of tubal ectopic pregnancies showing signs of rupture by six weeks of gestational age 1.…”

Unruptured tubal pregnancy in early second trimester

“…The possibility of intact endosalpinx epithelium and the absence or minimal hemorrhagia can be seen in intraluminal trophoblastic spread, but trophoblastic invasion of the maternal blood vessels is more intensive and tubal rupture occurs earlier in extraluminal extension [18]. The appearance and regularity of the gestational sac and the presence of crescent-shaped visible placental tissue (other authors also used similar diagnostics criteria before surgery) were the guidelines in making differential diagnosis between abdominal and tubal pregnancy [19]. We decided to perform lower transverse laparotomy due to low probability of abdominal pregnancy.…”