Products of conception evacuated from a 24-year-old woman at 12 weeks show fetal parts along with focal hydropic villi. What is the typical karyotype and origin of this gestation?
- A Triploid, commonly 69,XXY, from fertilisation of a normal ovum by two sperm ✓
- B 46,XX, entirely paternally derived
- C 45,X, from monosomy with empty sac
- D Tetraploid, from failure of the first zygotic division
Correct answer: A. Triploid, commonly 69,XXY, from fertilisation of a normal ovum by two sperm
Explanation
Focal villous oedema with fetal tissue defines a partial hydatidiform mole, which is almost always triploid, diandric and monoglossic, arising from dispermy, with karyotypes 69,XXY or 69,XXX. Option B describes a complete mole, which lacks fetal tissue and carries only paternal chromosomes. Complete moles are diploid, not polyploid, which eliminates the tetraploid distractor.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.