494 Obstetrics and Gynecology Board Review •••
❍ What are the features of complete hydatidiform moles?
(1) Complete hydatidiform moles lack identifiable embryonic or fetal tissues.
(2) Most commonly results from an ovum that has been fertilized by haploid sperm that then duplicates its own
chromosomes.
(3) The most common karyotype is 46XX followed by 46XY (5%)
(4) Diffuse villous edema
(5) Postmolar malignant sequelae 6% to 32%.
❍ What are the features of a partial mole?
(1) Identifiable embryonic or fetal tissues.
(2) Partial moles usually have a triploid karyotype (69XXX or 69XXY) with the extra haploid set of chromosomes
derived from the father.
(3) Focal villous edema.
(4) Postmolar malignant sequelae <5%.
❍ How does age influence the incidence of hydatidiform moles?
Compared with women 20 to 29 years of age, women over the age of 50 have a marked increase in risk, as well as
women under the age of 15. Similarly, increased paternal age (above 45 years of age) also confers an increased risk
of a complete molar pregnancy, although the increase is only 4.9 times (2.9 when adjusted for maternal age).
❍ What are the signs and symptoms of an incomplete molar pregnancy?
In general, these patients present with signs and symptoms of incomplete or missed abortion (amenorrhea, vaginal
bleeding, absent fetal heart tones), and the diagnosis may only be possible after histologic review of curettings.
❍ What is the most common presenting symptom in a complete mole?
Vaginal bleeding
Other symptoms of complete mole include:
(1) Excessive uterine size (50%).
(2) Theca lutein cysts [due to increased serum levels of beta-human chorionic gonadotropin (beta-hCG) and
prolactin].
(3) Hyperemesis gravidarum (25%) (due to markedly elevated beta-hCG).
(4) Hyperthyroidism (7%).
(5) Trophoblastic embolization.
(6) The presence of gestational hypertension during the first half of pregnancy should alert the possibility of molar
gestation.
❍ What is the term used to describe the sonographic findings of molar pregnancy?
Snowstorm pattern.
❍ How are patients with hydatidiform moles managed?
The diagnosis of complete or partial moles is usually made after performing suction D and C for a suspected
incomplete abortion. In these cases, patients should be monitored with serial determinations of quantitative hCG
values. A baseline postevacuation chest X-ray should be considered.