Overview

• Hydatidiform Mole → type of tumour that grows like a pregnancy inside the uterus. Arises due to an imbalance of paternal and maternal chromosomes.
  • Complete Mole → when two sperm cells fertilise an ovum that contains no genetic material (empy ovum). No fetal material will form + snowstorm appearance.
    • Empty Egg (46XY or 46XX).
  • Partial Mole → when two sperm cells fertilise a normal ovum at the same time. New cell has three sets of chromosomes. Some fetal material may form + no snowstorm appearance.
    • 69XXX or 69XXY (1x maternal and 2x paternal origin).
• Usually occurs at extremes of fertility range → in those <16 and >45 years of age.

<aside> 💡 Spectrum → partial hydatidiform mole, complete hydatidiform mole (10-15% go on to become invasive), choriocarcinoma (2.5% of complete moles).

</aside>

• Risk Factors → extremes of reproductive age, previous GTD, ethnicity (asian), diet.

Making Diagnosis

Clinical Features

• More severe nausea & vomiting.
• Vaginal bleeding.
• Abnormally high hCG.
• Enlarged large-for-dates uterus.
• Thyrotoxicosis (hCG can activate TSH receptors).

Investigations

• TVUSS → ‘snowstorm appearance’ (solid collection of echoes with numerous small anechoic spaces).
  • Indicates complete mole. Partial mole would have foetal parts present (no snowstorm appearance).
• b-hCG → significantly raised.
• High Thyroxine + Low TSH (negative feedback).