A hydatidiform mole refers to a condition where trophoblastic cells proliferate abnormally after conception, causing severe edema in the placental stroma. This leads to the formation of fluid-filled vesicles of varying sizes that connect in clusters, resembling grapes. It is also known as a hydatidiform mole (HM). Hydatidiform moles are classified into two types: ① Complete hydatidiform mole: All placental villi are affected, filling the entire uterine cavity with vesicles. There is diffuse trophoblastic proliferation, with no visible fetal or embryonic tissue.② Partial hydatidiform mole: Partial swelling and degeneration of placental villi with localized trophoblastic cell proliferation. Embryonic and fetal tissue may be present, but fetuses are often dead. Occasionally, viable fetuses smaller than gestational age or teratomas may be observed. Live births at term are extremely rare.
Malignant Hydatidiform Mole
When a hydatidiform mole invades the uterine muscle layer or metastasizes to other sites, it is termed "malignant hydatidiform mole."Most malignant hydatidiform moles occur within 6 months after hydatidiform mole evacuation, though malignant transformation can also occur before complete evacuation. The exact cause of malignant transformation remains unclear to experts, though medical theories include embryonic death, nutritional factors, viral factors, etc., and it is associated with chromosomal abnormalities.
What are the prevention methods for hydatidiform mole?
Chemotherapy for all patients to prevent the 15% malignant transformation rate is not suitable for widespread implementation in China. Therefore, selective use of chemotherapy combined with rigorous follow-up does not compromise the early detection and treatment of malignancy.
Regarding hysterectomy for hydatidiform mole patients, there is currently significant debate.Some experts argue that while hysterectomy cannot prevent malignancy, it reduces the risk, with lower malignant transformation rates compared to uterus retention. Therefore, hysterectomy may be considered for older patients without future pregnancy desires. Direct hysterectomy carries a lower risk of malignancy than hysterectomy performed after suction curettage. However, a 1984 WHO study demonstrated higher malignant transformation rates following hysterectomy.
This may occur because surgical compression of the uterus allows hydatidiform moles to invade uterine or ovarian veins via blood sinuses in the uterine wall. If these invading tissues are not removed during surgery, they can later metastasize. Therefore, abdominal hysterectomy is not recommended. For older patients insisting on surgery, it is advisable to observe for a period after curettage until hCG levels return to normal before proceeding with surgery.
The following points should be noted for hydatidiform mole management:
Regular Follow-up
Given the 10–20% risk of malignant transformation, patients require ongoing monitoring. After evacuation, weekly urine hCG testing is mandatory until negative results are confirmed. Subsequently, testing should occur monthly for the first six months, then quarterly thereafter, with a minimum follow-up period of two years.
Effective Contraception
Avoid sexual intercourse and baths for one month post-evacuation.Normal sexual activity is encouraged after molar pregnancy, but strict contraception must be maintained for 2 years to prevent recurrence and avoid confusion with malignant transformation. Appropriate exercise After discharge, patients may engage in light physical activities suited to their constitution, such as walking, jogging, or practicing Tai Chi, avoiding strenuous exertion. Light household chores are permissible, and adequate sleep should be ensured.
Maintain a Positive Mindset
Patients should cultivate a positive outlook and emotional state, adopting an optimistic attitude to combat the disease and enhance their resistance to illness.