Eclampsia in association with partial molar pregnancy and congenital abnormalities

Maternal complications in molecularly confirmed diandric and digynic triploid pregnancies: single institution experience and literature review

Objectives

Assessment of the maternal complications in molecularly confirmed diandric and digynic triploid pregnancies.

Methods

Sonographic features, biochemical results, and clinical presentation were analyzed. Beta-hCG level was controlled after diandric triploidy.

Results

The study included nine diandric and twelve digynic triploid pregnancies at the mean gestational age at diagnosis of 14.9 and 18.0 weeks, respectively (p = 0.0391). Mean value of total-hCG was 979 703.6 U/ml in diandric cases and 5 455.4 U/ml in digynic ones (p < 0.000). Maternal complications occurred in 88.9% of diandric triploid pregnancies, including: thecalutein cysts (44.4%), hyperemesis gravidarum (44.4%), symptomatic hyperthyreosis (33.3%), early onset gestational hypertension (22.2%) and vaginal bleeding (11.1%). No case of proteinuria, preeclampsia or HELLP syndrome was observed. Only maternal complication observed in digynic triploidy was vaginal bleeding (50.0%). The mean time of beta-hCG normalization after diandric triploid pregnancies was 84 days (range 11–142 days). No case of gestational trophoblastic neoplasia (GTN) was observed.

Conclusions

Maternal complications (except for vaginal bleeding) are associated with diandric triploidy. The relatively low incidence of hypertensive maternal complications and their less severe course in our cohort may be attributed to the earlier prenatal diagnosis. The frequency of GTN after diandric triploidy may be lower than previously reported.

Second trimester maternal serum analytes in triploid pregnancies: correlation with phenotype and sex chromosome complement

Second trimester maternal serum alpha-fetoprotein (MS-AFP), human chorionic gonadotrophin (hCG), unconjugated estiol (uE3), and inhibin-A (INH-A) levels were evaluated in pregnancies complicated by triploidy. In addition to seven new triploid pregnancies, the results for 67 published cases were reviewed. All cases appear to fall into two major groups. First, those identifiable as screen-positive for both Down syndrome and an open neural tube defect (ONTD) with elevated MS-AFP, grossly elevated hCG, low/normal uE3, and probably elevated INH-A. Pregnancies in the second group are identifiable as screen-positive for trisomy 18 with low/normal MS-AFP, and very low hCG, uE3 and INH-A. Triploid pregnancies with high maternal serum hCG nearly always show a placenta with partial mole (25/27 or 93%), a high frequency of ONTDs or ventral wall defects (VWDs) (8/28 or 29%) and have either an XXX or XXY karyotype (observed ratio 6:10, respectively). Low hCG is infrequently associated with a molar placenta (1/11 or 9%), does not appear to be associated with ONTDs or VWDs (0/29 or 0%), and shows an excess of XXX over XXY karyotypes (observed ratio 17:2). There were 16 cases with either a molar placenta, an ONTD or a VWD that received the MS-AFP and hCG tests. All 16 were screen-positive for an ONTD (MS-AFP> or =2 multiples of the median). In addition, all 31 cases that received MS-AFP, hCG, uE3 (and where available INH-A) were screen-positive for either Down syndrome or trisomy 18. The findings are discussed in the context of expected differences between digynic and diandric triploidy. It is suggested that the sex chromosome complement in triploidy is an important factor in determining risk for partial mole development and in utero survival.

Inhibition of TGF-beta 3 restores the invasive capability of extravillous trophoblasts in preeclamptic pregnancies

Preeclampsia, the major cause of maternal morbidity and mortality in developed countries, is associated with abnormalities of placenta function due to shallow invasion of the maternal decidua by trophoblasts. Data suggest that TGF-beta may play a role in inhibiting trophoblast outgrowth or invasion, or both. We report that placental TGF-beta 3 expression is high in early pregnancy but falls at around 9 weeks' gestation. This pattern is inversely correlated with trophoblast outgrowth and fibronectin synthesis, markers of early trophoblast differentiation toward an invasive phenotype. We demonstrate that TGF-beta 3 is overexpressed in preeclamptic placentae. In contrast to control placentae, explants from preeclamptic pregnancies fail to exhibit spontaneous invasion in vitro. Significantly, antisense-induced inhibition of TGF-beta 3 expression, and inhibition of TGF-beta 3 activity with antibodies, induces the formation of columns of trophoblast cells, which migrate out of the explant into the underlying Matrigel. To our knowledge, this is the first demonstration that the hypoinvasive placental phenotype characteristic of preeclampsia can be essentially normalized in vitro by biochemical manipulation. We speculate that a failure to downregulate expression of TGF-beta 3 at around 9 weeks' gestation results in shallow trophoblast invasion and predisposes the pregnancy to preeclampsia.

Early prenatal diagnosis of triploidy

OBJECTIVE

Our purpose was to investigate the role of ultrasonography and maternal serum human chorionic gonadotropin in the early prenatal diagnosis of triploid pregnancies.

STUDY DESIGN

A retrospective study on 61,314 consecutive singleton pregnancies examined by ultrasonography at 10 to 14 weeks' gestation was performed to identify the prenatal features of those complicated by triploidy. When available, the serum human chorionic gonadotropin level was measured and ascertained retrospectively. Cases lost to follow-up or for which no karyotype was available were excluded from the final analysis.

RESULTS

Overall there were 18 cases of triploidy identified in a population of 58,862 singleton pregnancies, giving a prevalence of 1 in 3270. Fetal defects were observed in 8 (44.4%) of these cases; these included holoprosencephaly (n = 4), exomphalos (n = 3), and posterior fossa cyst (n = 1). In 6 (33.3%) cases the placenta showed molar changes. The fetal crown-rump length was below the 5th percentile in 10 of the 16 (62.5%) cases for which the menstrual age was also available. Fetal nuchal translucency thickness was above the 95th percentile in 12 (66.7%) cases, and the fetal heart rate was below the 5th percentile in 4 of the 13 (30.8%) cases evaluated. The maternal human chorionic gonadotropin level was high in 11 of the 13 (84.6%) cases tested, with similar distribution of the high values in molar and nonmolar triploidies.

CONCLUSION

The combination of ultrasonographic examination of the fetoplacental features and measurement of the maternal serum level of human chorionic gonadotropin enables the diagnosis of most cases of triploidy at 10 to 14 weeks' gestation.