Chromosome abnormalities in the placenta and spontaneous abortions

Abstract

Data are presented confirming that placental chromosome abnormalities are more important than fetal chromosome abnormalities in determining fetal loss. Improved methodologies for studying chromosome abnormalities in spontaneous abortion (SAB) are presented that include results for 141 cases (gestational ages 6–24 weeks) with karyotypic study on placental as well as fetal tissue. Experience in two laboratories gave a success rate of >90% of specimens with identifiable placental tissues, an average turnaround time of 10 days for those that produced chromosome results, male‐to‐female ratio of >50% (indicating no impact of maternal cell contamination), and 30% of cases had chromosome abnormalities. More significantly, two cases (5% of all abnormal cases) showed an abnormal karyotype limited to the placenta. This illustrates the need to examine the placenta in cases of SAB and the importance of technical issues in laboratory studies. J. Matern.–Fetal Med. 7:210–212, 1998. © 1998 Wiley‐Liss, Inc.

Array comparative genomic hybridization profiling of first‐trimester spontaneous abortions that fail to grow in vitro

“…The most common findings in cultured products of conception that divide to produce analyzable metaphases are trisomy 16, monosomy X, and triploidy. These three findings account for over 55% of all cytogenetically abnormal findings in routine studies by G-banding (Warburton et al, 1979;Qumsiyeh, 1998). Further, we found structural abnormalities such as amplification of a small area of the X chromosome and deletion of autosomal material.…”

“…Classic cytogenetic studies are offered in some institutions for SABs or intrauterine fetal demise and for parents who had a history of repeated SABs. These studies entail conventional tissue culturing and karyotyping and have limitations such as a high rate of culture failure and maternal cell contamination (Qumsiyeh, 1998;Lomax et al, 2000).…”

The haplotypes GCA and ACA in ESR1 gene are associated with the susceptibility of recurrent spontaneous abortion (RSA) in Chinese Han

“…Recurrent spontaneous abortions (RSAs) are spontaneous abortions that occur 3 or more times in a row with the same partner and affect approximately 1% to 2% of couples. [ 1 , 2 ] Complex etiologies including infection, [ 3 ] autoimmune diseases, [ 4 ] environmental factors, [ 5 ] and chromosomal abnormalities, [ 6 , 7 ] are associated with RSA risk. In addition, 50% affected women with RSA have no specific causes, which is defined as unexplained spontaneous recurrent abortion.…”