Distribution of diandric and digynic triploidy depending on gestational age

Abstract

Purpose To establish the distribution of diandric and digynic triploidy depending on gestational age. Methods 107 triploid samples tested prospectively in a single genetic department during a four-year period were analyzed for parental origin of triploidy by Quantitative Fluorescent Polymerase Chain Reaction (QF-PCR) (n=95) with the use of matching parental samples or by MS-MLPA (n=12), when parental samples were unavailable. Tested pregnancies were divided into three subgroups with regard to the gestational age at spontaneous pregnancy loss: <11 gestational weeks, 11–14 gestational weeks, and >14 gestational weeks. Results Diandric triploidy constituted overall 44.9% (46.5% in samples miscarried <11 gestational weeks, 64.3% in samples miscarried between 11 and 14 gestational weeks, and 27.8% in pregnancies which survived >14 gestational weeks). Conclusions The distribution of diandric and digynic triploidy depends on gestational age. The majority of diandric triploid pregnancies is lost in the first trimester of pregnancy. In the second trimester, diandric cases are at least twice less frequent than digynic ones.

Polyploidy Phenomenon as a Cause of Early Miscarriages in Abortion Materials

“…A possible dyspermia may be the source of an extra set of paternal chromosomes. The prevalence of paternal (diandric) triploidy varies between 20% and 85% in various studies and the vast majority of them are lost in the first trimester of pregnancy [ 36 ]. Most triploidies may have paternal origin, and diandric triploidy can often be diagnosed as partial hydatidiform moles with abnormal placentas characterized by trophoblastic proliferation [ 37 ].…”

Analysis of copy number variations and possible candidate genes in spontaneous abortion by copy number variation sequencing

“…In this study, we also explore the correlation between gestational weeks and fetal chromosomal abnormalities. Previous research has suggested that the incidence of chromosomal abnormalities in fetuses is higher during early pregnancy than in the mid-pregnancy phase ( 30 ), and triploidy occurs more frequently in pregnancies of less than 11 weeks gestational age ( 41 ). However, we did observe no significant difference in the detection rates of fetuses with normal karyotypes in different gestational ages, and the proportion of mosaicisms in abnormal karyotypes decreased with increasing gestational age, while the proportion of sex chromosome monosomy and polyploidy in abnormal karyotypes increased with gestational week.…”

Morphology combined withHER2D-DISH ploidy analysis to diagnose partial hydatidiform mole: an evaluation audit using molecular genotyping

“…The distribution of diandric and digynic triploidy has been reported differently depending on gestational age. [22][23][24] Typically, digynic triploid conceptions do not display morphological features of molar pregnancy but on occasion can exhibit some focal dysmorphic features suggestive of a PHM. 7 25 A digynic triploid conceptus may manifest on ultrasound with a growth restricted fetus, with relative macrocephaly and a non-cystic placenta but these abnormalities can be subtle and may be missed in the first trimester.…”