Suspected ovarian molar pregnancy after assisted reproductive technology conception: a diagnostic challenge

Abstract

A 32-year-old patient with primary infertility received in vitro fertilisation (IVF) therapy. Four weeks later she developed intermittent left iliac fossa pain. Transvaginal ultrasound showed an empty uterus and an adnexal mass adjacent to the right ovary. Serum β-human chronic gonadotropin was 33,492 IU/L. At laparoscopy a mass attached to right ovary, suggestive of a right ovarian ectopic pregnancy, was excised. Histological examination confirmed an ovarian ectopic gestation, but noted enlarged chorionic villi and trophoblastic atypia, which raised the suspicion of molar pregnancy. Subsequent p57 immunohistochemistry and DNA ploidy studies excluded a mole, however. Cases of suspected molar disease in ectopic pregnancy present a diagnostic challenge for both clinicians and histopathologists, and establishing a definitive diagnosis may be difficult.

Figure 1

Pelvic ultrasound showing an enlarged right ovary and free fluid in the pelvis, suggestive of ectopic pregnancy.

Figure 2

Laparoscopic picture of the pelvis with haemoperitoneum and an enlarged and abnormal right ovary.

Figure 3

H&E slide showing (A) Variably-sized chorionic villi with some hydropic forms (B) Foci of trophoblast hyperplasia.

Figure 4

Positive p57 staining in villous mesenchyme and cytotrophoblast. This staining pattern excludes complete mole, but cannot distinguish between a hydropic abortion and a partial mole.