Recurrent consecutive partial molar pregnancy

Recurrent Partial Hydatidiform Mole: A Case Report of Seven Consecutive Molar Pregnancies

Hydatidiform mole (HM) is an aberrant pregnancy characterized by atypical trophoblastic hyperplasia, hydropic chorionic villi, and deprived fetal development. There are two types of HM, ie, complete (CHM) and partial (PHM). Both CHM and PHM can recur; however, the recurrence of PHM is very scarce compared to CHM. In this report, we present a case of a 33-year-old woman with recurrent PHM for 7 times without any normal pregnancy in-between. PHM was determined by histology examination. The patient underwent suction curettage and was followed up with serial β-hCG levels. Recurrent PHM, although rare, is associated with an increased incidence of malignancy. A series of clinical and β-hCG evaluation should be warranted because of the possibility of gestational trophoblastic neoplasia development.

Biparental hydatidiform moles: a maternal effect mutation affecting imprinting in the offspring

Highly recurrent hydatidiform moles (HMs) studied to date are not androgenetic but have biparental genomic contribution (BiHM). Affected women have an autosomal recessive mutation that causes their pregnancies to develop into HM. Although there is genetic heterogeneity, a major locus maps to chromosome 19q13.42, but a mutated gene has not yet been identified. Molecular studies have shown that maternal imprinting marks are deregulated in the BiHM trophoblast. The mutations that cause this condition are, therefore, hypothesized to occur in genes that encode transacting factors required for the establishment of imprinting marks in the maternal germline or for their maintenance in the embryo. Although only DNA methylation marks at imprinted loci have been studied in the BiHM, the mutation may affect genes that are essential for other forms of chromatin remodelling at imprinted loci and necessary for correct maternal allele-specific DNA methylation and imprinted gene expression. Normal pregnancies interspersed with BiHM have been reported in some of the pedigrees, but affected women repeatedly attempting pregnancy should be counselled about the risk for invasive trophoblastic disease with each subsequent BiHM.

Recurrent partial hydatidiform mole: a report of a patient with three consecutive molar pregnancies

Hydatidiform mole (HM) is the most common form of gestational trophoblastic neoplasia and is characterized by atypical hyperplastic trophoblasts and hydropic villi. Recurrence of HM is extremely rare. Here, we report the case of a patient with three consecutive partial HMs without normal pregnancy. A 28-year-old woman with gravida 3, para 0, was referred to our hospital with a diagnosis of an invasive mole in December 2003. She had three consecutive molar pregnancies in 2000, 2001, and 2003. All three molar pregnancies were evacuated by suction curettage and the patient was followed by serial beta-human chorionic gonadotropin levels. All three moles were histologically confirmed as partial moles. In the first two molar events no additional treatment after evacuation was required, but in the last event, the beta-human chorionic gonadotropin levels increased and an invasive mole was suspected. Diagnostic workup ruled out an invasive mole and choriocarcinoma. Karyotypic analysis of the patient and her husband was normal. The patient required chemotherapy for treatment of persistent disease. Recurrent partial HM is a very rare clinical disorder. Repetitive molar pregnancy is not an indication for chemotherapy, but persistent disease does require chemotherapy.

Familial hydatidiform molar pregnancy: the germline imprinting defect hypothesis?

Imprinting is the uniparental expression of a set of genes. Somatic cells carry two haploid sets of chromosomes, one maternal and one paternal, while germ cells contain only one of the two forms of chromosomes, male or female. This implies that during early embryogenesis the cells committed for developing the future germ cell lineage, the primordial germ cells, which are diploid, have to undergo a total chromosome reprogramming process. This process is delicately controlled during gametogenesis to ensure that males and females have only their respective form of gametes. The machinery involved in this process is yet poorly defined. Familial hydatidiform molar (HM) pregnancy is an abnormal form of pregnancy characterized by hydropic degeneration of placental villi and abnormal, or absence of, embryonic development. To date, the molecular defect causing this condition is unknown. However, in a few studied cases, the presence of paternal methylation patterns on the maternal chromosomes was observed. In this chapter, we summarize what is known about methylation aberrations in HMs and examine more closely the proposed hypothesis of a maternal germline imprinting defect.