Author:
Johanna E.Kreafle
Joshua W.Loyd
Description
- A gestational trophoblastic disease (GTD), which originates from the placenta and can locally invade the uterus and /or metastasize
- Tumor arises from gestational rather than maternal tissue
- Potential to develop into a malignancy:
- Gestational trophoblastic neoplasia (GTN)
- Complete mole:
- Estimated in 1/1,500 pregnancies
- Fetal tissue not present
- Diffuse chorionic villi swelling
- Diffuse trophoblastic hyperplasia
- Malignancy develops in 15-20%:
- If metastasizes, usually to lung
- Genetics:
- Karyotype: 46XX (80%); 46XY (20%)
- Paternal DNA expressed
- Enucleate egg fertilized by 2 sperm or by a haploid sperm that duplicates
- Partial mole:
- Estimated in 1/750 pregnancies
- Fetal or embryonic tissue often present
- Focal chorionic villi swelling
- Focal trophoblastic hyperplasia
- Malignancy develops in 1-5%
- Genetics:
- Karyotype: 90% are triploid 69XXX, 69XXY, rarely 69XYY
- Maternal and paternal DNA
- Haploid ovum fertilized by 2 sperms or haploid ovum duplicates and is fertilized by normal sperm
- Twinning with normal pregnancy possible w/partial mole:
- Higher risk for persistent maternal disease and metastasis
- Possible to have normal infant
Etiology
- Largely unknown
- Risk factors:
- Extremes of maternal age best estimated risk factor:
- >35 yr old carries 2-7.5-fold risk
- <15 yr old
- Previous molar pregnancy carries 1-2% risk in future pregnancies (10-15 times the risk for general population)
- Deficiency in animal fat and vitamin A
- Smoking (>15 cigs/d)
- Maternal blood type AB, A, or B
- History of infertility and /or spontaneous abortions
- Varies based on geography:
- Asian countries have highest risk
- U.S. and Western Europe have lowest risk (1 per 1,000-1,500 live births)
- Reported up to 1 per 12-500 live births in other countries
- Finding in 1 of 600 therapeutic abortions
Signs and Symptoms
- Usually exaggerated subjective symptoms of pregnancy
- Complete mole:
- Vaginal bleeding:
- Most common symptom
- Due to separation of molar villi from underlying decidua
- Late first trimester
- Usually painless and like “prune juice”
- May also have vaginal tissue passage:
- Often described as grapelike vesicles
- Usually occurs in second trimester <20 wk
- Hyperemesis, likely from high levels β-hCG
- Preeclampsia at <20 wk gestation:
- Visual changes
- HTN
- Proteinuria
- Hyperreflexia
- Possibly convulsions (eclampsia)
- Hyperthyroidism:
- Marked tachycardia, tremor
- Possibly due to high levels of β-hCG (>100,000 mIU/mL) or thyroid stimulating substance (thyrotropin)
- Acute respiratory distress:
- Tachypnea, diffuse rales, tachycardia, mental status changes
- Possible embolism of trophoblastic tissue
- May also be due to cardiopulmonary changes from preeclampsia, hyperthyroidism, or iatrogenic fluid replacement
- Partial mole:
- Usually does not exhibit dramatic clinical features of complete mole
- Frequently presents with symptoms similar to patients with threatened or spontaneous abortion:
- Vaginal bleeding
- May have fetal heart tones
- Often presents at more advanced gestational age
History
- Often similar to that of pregnancy:
- Missed menstrual periods
- Positive pregnancy test
- Nausea, vomiting, vaginal bleeding
Physical Exam
- Uterine size/date discrepancy occurs in 50-66% of cases:
- Complete mole usually larger than dates would indicate
- Partial mole can be smaller than dating suggests
- Ovarian masses:
- Present in complete moles, rarely in partial moles
- Usually from ovarian enlargement
- Multiple bilateral theca lutein cysts due to high levels of β-hCG, usually found by US
Essential Workup
- β-hCG:
- Complete mole usually β-hCG >100,000 mIU/mL, but can be normal
- Partial mole β-hCG usually lower than that seen with normal pregnancy
- β-hCG >40,000 mIU/mL carries poor prognosis
- US:
- Complete mole:
- Characteristic “snowstorm” vesicular pattern
- Absence of fetal tissue and swelling of chorionic villi with anechoic spaces
- No amniotic fluid
- Ovarian theca lutein cysts
- Enlarged uterus
- Partial mole:
- “Swiss-cheese” appearance
- Cystic changes in placenta with scalloping of villa and in shape of gestational sac
- Fetus may be present
- Amniotic fluid is present, but volume may be reduced
- Normal appearing fetus with β-hCG >100,000:
- Repeat β-hCG and US in 1 wk
- Could be twin gestation vs. partial mole
Diagnostic Tests & Interpretation
Lab
- β-hCG
- Blood type, Rh, and cross-match
- CBC to assess for anemia and thrombocytopenia
- Coagulation profile to assess for disseminated intravascular coagulation (DIC)
- Electrolytes with BUN and creatinine
- LFTs
- TSH and thyroxin (free T4) if hyperthyroidism suspected
- Urinalysis to evaluate for protein if preeclampsia suspected
Imaging
- US:
- May be performed at bedside
- Transvaginal US more sensitive than transabdominal
- CXR:
- Assess for pulmonary edema in acute respiratory distress
- Check for metastatic disease
- For baseline study
Pathology/Histology
- All conception products should be sent for formal evaluation
- Products may be the only way to diagnose a partial molar pregnancy
- Complete mole:
- Edematous chorionic villi
- Hyperplasia of trophoblasts
- Partial mole:
- Fetal tissue and vessels
- Amnion
- Edematous chorionic villi
Differential Diagnosis
- Ectopic pregnancy
- Eclampsia/preeclampsia
- Thyroid storm/hyperthyroidism
- Threatened abortion
- Missed abortion
- Incomplete abortion
- Hyperemesis gravidarum
- Nonmolar pregnancy
Prehospital
- Ensure patent airway
- Provide oxygen p.r.n
- IV access
- Treat convulsions with magnesium sulfate and benzodiazepines
- Save passed tissue for histologic evaluation
Initial Stabilization/Therapy
- Ensure patent airway
- IV access
- Cardiac monitoring
- Type and cross-match for blood, if heavy bleeding/shock
ED Treatment/Procedures
- Acute respiratory distress:
- CXR may show infiltrates:
- Possibly related to trophoblastic embolization, thyroid storm, or iatrogenic fluid resuscitation
- NIPPV or intubation may be required
- Hyperthyroidism:
- Resolves with treatment of molar pregnancy
- β-adrenergic blockers:
- Propranolol recommended
- Administer before molar evacuation
- Stress of anesthesia or surgery may precipitate thyroid storm
- Preeclampsia/eclampsia:
- Resolves with treatment of molar pregnancy
- Convulsions:
- Administer benzodiazepines (midazolam)
- Administer magnesium sulfate
- Severe hypertension (BP ≥160/110):
- Coagulopathy:
- Transfuse with blood products as needed
- Human anti-D immunoglobulin (RhoGAM):
- Although fetal blood not present in complete mole, may be delayed in distinguishing partial vs. complete
- Suction curettage:
- Done by obstetrician, possibly in ED
- Curative in 80% of cases
- Method of choice in women wishing to preserve fertility
- Oxytocin infusion to induce myometrial tone, may require other uterotonic formulations
- Hysterectomy:
- Patients in older age group
- Patients not interested in keeping fertility
- High-risk disease
- Does not necessarily prevent metastasis
- Chemoprophylaxis:
- Very controversial
- Prescribed by obstetrician only for patients with follow-up
- Usually used in high-risk complete mole or if hormonal monitoring is unavailable
Medication
- Hydralazine: 5-10 mg IV q20min, up to 60 mg
- Labetalol: 10-20 mg IV with doubled dosing q10m for max 300 mg
- Magnesium sulfate: 4-6 g IV over 15-20 min then maintain 1-2 g/hr
- Midazolam: 1-2 mg IV over 1 min q5min, up to 0.4 mg/kg
- Oxytocin 10 units IM or 40 units in 1-L IVF at 1-6 milliunits/min
- Propranolol: 1 mg IV increments q2m
- RhoGAM: 300 mcg IV/IM within 72 hr
Disposition
Admission Criteria
- Enlargement of uterus beyond 16-wk gestation size:
- The larger the uterus, the greater the risk for uterine perforation during suction curettage, hemorrhage, and pulmonary complications due to embolism
- Clinical evidence of preeclampsia, hyperthyroidism, respiratory distress
- Hysterectomy
- Partial molar pregnancy
- Hemodynamic instability
Discharge Criteria
- Uncomplicated dilation and curettage of low-risk and small-size mole in reliable patient
- Stress the importance of follow-up
- Pelvic rest for 4-6 wk after uterine evacuation
- Recommend no pregnancies for 12 mo
- Future pregnancies should have early sonographic evaluation due to increased risk in future pregnancies
Follow-up Recommendations
- Close follow-up and monitoring by OB-GYN
- Serial β-hCG levels:
- Obtained weekly for at least 4 wk, then monthly intervals
- Levels should consistently drop and never increase
- If increase is noted, evaluate for GTN and metastatic disease
- Use contraception:
- Pregnancy can complicate interpretation of β-hCG and management of GTN
- IUD contraindicated
- US:
- Early in all future pregnancies
- Increased risk for future molar pregnancies (1-2% with second mole, 20% after 2 moles)
- BerkowitzRS, GoldsteinDP. Clinical practice. Molar pregnancy . N Engl J Med. 2009;360:1639-1645.
- MastersonL, ChanSB, BluhmB. Molar pregnancy in the emergency department . West J Emerg Med. 2009;10:295-296.
- MelamedA, GockleyAA, JosephNT, et al. Effect of race/ethnicity on risk of complete and partial molar pregnancy after adjustment for age . Gynecol Oncol. 2016;143:73-76.
- SebireNJ, SecklMJ. Gestational trophoblastic disease: Current management of hydatidiform mole . BMJ. 2008;337:a1193.
- SunSY, MelamedA, JosephNT, et al. Clinical Presentation of complete hydatiform mole and partial hydatiform mole at a regional trophoblastic disease center in the united state over the past 2 decades . Int J Gynecol Cancer. 2016;26:367-370.
See Also (Topic, Algorithm, Electronic Media Element)