Hydatidiform mole is a benign tumour of Trophoblast.
Complete mole: no fetus is present and the chromosomal complement is totally paternal.There are 46 chromosomes.Partial mole: fetus is present. There are 69 chromosomes and the extra set is of partenal origin. Invasive mole: may penetrate the uterus and /or metastasize to the lungs.
The symptoms are usually irregular bleeding in the first trimester of pregnancy. The uterus may be larger than dates and the fetal heart is usually absent. Preeclampsia may develop early, and the calutein cysts may be palpable.
Ultrasound will demonstrate a ‘snowstorm’ appearance, and the fetus will not be seen. Beta HCG level is very high. A chest X-ray should be done to exclude pulmonary metastases.
Suction evacuation of the hydropic vesicles. If uterine size is too large, extra-amniotic prostaglandins are used. Hysterectomy may be done in the older woman. It is essential to follow all women to ensure that the Beta HCG levels disappear. Pregnancy should be discouraged for at least 12 months.
One in 30 moles develops into chloriocarcinoma malignant tumour of trophoblastic tissue. Chemotherapy is the mainstay of treatment and close follow-up is essential.