Kimberly Woods McMorrow
History of present illness
A 21-year-old gravida 2, para 1 woman at 14 weeks 0 days by sure last menstrual period presents with a 2-day history of lower abdominal cramping and vaginal spotting requiring her to wear a pad. She complains of some nausea which has been well controlled with odansetron. She has not yet received any prenatal care due to a lack of insurance. She is healthy and does not report any other medical problems. She delivered her first baby by Cesarean about a year ago for malpresentation.
She denies a history of sexually transmitted infections and does not smoke, drink alcohol, or use illicit drugs.
Physical examination
General appearance:Anxious-appearing woman in no acute distress
Vital signs:
Temperature: 37.0°C Pulse: 125 beats/min
Blood pressure: 111/55 mmHg Respiratory rate: 16 breaths/min Oxygen saturation: 99% on room air Cardiovascular:Tachycardic, regular rhythm
Pulmonary:Lungs clear to auscultation bilaterally Abdomen:Soft, nontender, uterus palpable threefinger breadths above the umbilicus, absent fetal heart tones on Doppler
External genitalia:Unremarkable Pelvic:
Speculum examination: Normal appearing cervix, minimal blood in vaginal vault, no discharge
Bimanual examination: Approximately 24–26 weeks’size nontender uterus, cervix closed, no cervical motion tenderness, no adnexal tenderness or masses Laboratory studies:
WBCs: 6500/μL Hb: 8.3 g/dL Ht: 24.3%
Platelets: 293 000/μL
Thyroid-stimulating hormone:<0.01 mIU/mL Quantitative beta-hCG: 2.8 million
Blood type: O positive
Imaging:Transvaginal ultrasound performed.
Multiple vesicles noted throughout uterus. No intrauterine pregnancy noted. Unable to visualize ovaries bilaterally (Fig. 26.1)
Acute Care and Emergency Gynecology, ed. David Chelmow, Christine R. Isaacs and Ashley Carroll. Published by Cambridge University Press.
© Cambridge University Press 2015.
Fig. 26.1Sagittal ultrasound image of the uterus.
Note the vesicular pattern, characteristic of hydatidiform mole. (Image provided by Steven Cohen MD.)
How would you manage this patient?
The patient has a molar pregnancy. Her tachycardia is a result of hyperthyroidism induced by the extremely elevated beta-human chorionic gonadotropin (beta-hCG) level. She needs a suction dilation and curettage (D&C). Her tachycardia and hyperthyroid symptoms should resolve after treatment of the molar pregnancy. Following surgery, her quantitative beta-hCG levels need to be followed until they are negative and then continued to be followed to make sure they remain negative in order to rule out malignant post-molar gestational trophoblastic disease. She should be started on a reliable form of contraception and should be advised not to try to conceive again for at least six months after her hCG levels become negative.
Molar pregnancy
Hydatidiform mole is an abnormal pregnancy that classically shows vesicular swelling of the placental villi. The incidence varies throughout the world, but in the United States and Europe the incidence is approximately 0.6–1.1 per 1000 pregnancies. In Asia, the incidence is higher at 2–10 per 1000 pregnancies. Young women and women over age 40 are at an increased risk of molar pregnancy [1].
Hydatidiform moles may be classified as either complete or partial (Table 26.1). This patient has a complete mole. In a complete hydatidiform mole, the most common karyotype is 46,XX and usually occurs when a haploid sperm fertilizes an empty egg and duplicates. They are associated with diffuse villous edema and trophoblastic proliferation. A fetus is usu- ally absent. In a partial hydatidiform mole, the most common karyotype is 69,XXY with an extra haploid set of chromosomes from the father. A fetus is often present as are fetal red blood cells. Villous edema as well as trophoblastic proliferation are only focal. Partial moles are very similar to and often diag- nosed as a missed abortion [2].
Molar pregnancies are typically diagnosed in the first trimester of pregnancy. The most common symptom is vaginal bleeding. Other signs include uterine enlargement greater than the expected gestational age, absent fetal heart tone, cystic enlargement of the ovaries (theca lutein cysts), hyperemesis gravidarum, and an hCG level abnormally higher than what would be expected for gestational age. The diagnosis is
typically established using ultrasonography. Complete moles classically show a vesicular pattern on ultrasound [3].
This patient also showed signs of clinical hyperthyroidism induced by the excessively elevated hCG level. Clinical hyper- thyroidism has been reported in up to 7% of patients with a complete molar pregnancy but is now less common due to earlier diagnosis secondary to widespread ultrasonography.
These women may present with tachycardia, skin warmth, and tremor. Hyperthyroidism usually develops only in patients with extremely high hCG levels. Anesthesia or surgery may precipitate a thyroid storm; therefore, beta-blocking agents should be administered prior to induction of anesthesia [4].
The American College of Obstetricians and Gynecologists (ACOG) practice bulletin [3] recommends the following tests in patients who have a suspected hydatidiform mole: complete blood count with platelet count, clotting function studies, renal and liver function studies, blood type with antibody screen, hCG level, and chest x-ray. The preferred method of treatment in women who wish to preserve their fertility is suction D&C.
After dilation of the cervix, the largest suction cannula thatfits through the cervix should be used. Ultrasound guidance may sometimes be helpful to ensure that the uterus is completely evacuated. Oxytocin should be administered intravenously after dilation of the cervix and continued several hours post- operatively. Rh-negative patients should be given anti-D immune globulin after evacuation. For patients who do not wish to preserve their fertility, hysterectomy with ovarian preservation is acceptable. Medical induction of labor and hysterotomy are not acceptable management strategies because they are associated with increased blood loss and may increase the risk for subsequent malignancy.
After treatment, patients need to be monitored for the development of post-molar trophoblastic disease. The ACOG practice bulletin [3] recommends serial serum hCG assessments 48 hours after evacuation, every 1–2 weeks while elevated, and then at monthly intervals for an additional 6 months. Patients should use a reliable form of birth control during this period as a pregnancy may delay the diagnosis of post-molar tropho- blastic disease. Post-molar malignant trophoblastic disease is diagnosed when hCG levels plateau or begin to rise in the weeks following molar evacuation. Approximately 20% of patients will develop post-molar trophoblastic disease following the evacu- ation of a hydatidiform mole. In patients who have undergone hysterectomy, the risk of trophoblastic disease still remains at approximately 3–5%. Patients who develop post-molar tropho- blastic disease need to be treated with chemotherapy, most commonly methotrexate.
According to the ACOG practice bulletin [3], after six months of normal hCG levels, women may discontinue con- traception and attempt pregnancy again. Women who have had a prior partial or complete mole have a 10-fold increase or 1–2% incidence of a second hydatidiform mole in a second pregnancy. Future pregnancies should be evaluated with an early ultrasound and any products of conception or placentas should be evaluated by pathology.
Table 26.1 Characteristics of complete and partial hydatidiform moles Characteristic Complete mole Partial mole Karyotype 46,XX or 46,XY 69,XXX or 69,XXY
Fetus Absent Present
Villous edema Diffuse Focal
Trophoblastic
proliferation Diffuse Focal
Key teaching points
Hydatidiform moles typically present with abnormal vaginal bleeding in thefirst trimester of pregnancy. Other signs include uterine enlargement greater than expected for gestational age, absent fetal heart tones, theca lutein cysts of the ovaries, hyperemesis gravidarum, and abnormally elevated human chorionic gonadotropin (hCG) level.
Clinical hyperthyroidism is rare but may be present in cases where hCG is excessively elevated.
The diagnosis is typically established using ultrasonography which classically shows a vesicular pattern.
The treatment for molar pregnancy is evacuation of the uterus with suction dilation and curettage (D&C).
Hysterectomy may be considered for patients who do not wish to preserve their fertility.
Following treatment, hCG levels need to be monitored until they are negative and then for six months in order to evaluate for post-molar gestational trophoblastic disease.
Post-molar gestational disease is diagnosed when beta-hCG plateaus or rises following molar evacuation and is treated with chemotherapy.
References
1. Smith HO. Gestational trophoblastic disease epidemiology and trends.Clin Obstet Gynecol2003;46:541–56.
2. Lawler SD, Fisher RA, Dent J.
A prospective genetic study of complete
and partial hydatidiform moles.Am J Obstet Gynecol1991;164:1270–7.
3. American College of Obstetricians and Gynecologists. Diagnosis and treatment of gestational trophoblastic disease.
Practice Bulletin No. 53.Obstet Gynecol 2004;103:1365–77.
4. Walkington L, Webster J, Hancock BW, et al. Hyperthyroidism and human chorionic gonadotrophin production in gestational trophoblastic
disease.Br J Cancer2011;104:
1665–9.
Case 26: Tachycardia and vaginal bleeding in pregnancy