Spontaneous abortion occurs in 15-20% of clinically recognized gestations [ 1 ]. Genetic defects, especially chromosomal abnormalities, are the most common cause of spontaneous miscarriage during the first trimester; indeed, chromosomal abnormalities occur in approximately 60% of such cases [ 2 ].
Results: A total 406 specimens were referred to laboratory, ten abortuses were excluded, and in 14 cases, we did not get any spontaneous metaphase, chromosomal constitutions of 382 specimens were successfully obtained with conventional cytogenetic methods.
Infertile men with a normal karyotype and abnormal spermatogenesis have been shown to carry a significantly increased risk of producing aneuploid spermatozoa, particularly for the sex chromosomes [ 12, 21 – 23 ]. These studies are in accordance with the increased incidence of sex chromosomal abnormalities in the ICSI group.
The genetic factor remains the most frequent cause of spontaneous abortions. Examination of the fetal tissue from spontaneous miscarriages shows that 75% of them were caused by abnormal karyotype. Other reasons, albeit rare, included submicroscopic genomic rearrangements, monogenic diseases, and polygenic inheritance disorders of the embryo. The aim of the study was to analyze the incidence of chromosomal aberrations in material from the miscarriage. The study included 47 samples of miscarriage material from 47 women. Fluorescent hybridization in-situ (FISH) was used for genetic examination. Chromosomal abnormalities were diagnosed in 72% of the samples, with trisomy 21 (25.5%), trisomy 16 (17%), and trisomy 18 (12.8%) as the most common. An abnormal number of copies of chromosome 18, 21, 22, indicating the coexistence of trisomy 18, 21, 22, was detected in 1 patient. It was another miscarriage in case of 14 subjects (29.8%). Chromosomal aberrations were diagnosed in the majority of fetal tissue samples from spontaneous miscarriages. More than one chromosomal aberration in a single embryo is an extremely rare occurrence. Miscarriage due to chromosomal aberrations occurred in the vast majority of women > 35 years of age.
Chromosomal abnormalities are the most common causes of abortion in the first trimester. Most miscarriages in this term of pregnancy are due to aneuploidy, the frequency of which is 50–80%. Autosomal trisomy is the most common chromosomal abnormalities. The aim of the study was to investigate chromosomal abnormalities of abortive material in women with recurrent spontaneous abortion after in vitro fertilization and after natural fertilization. Cytogenetic and molecular cytogenetic studies include 440 samples of chorionic villi from women with recurrent miscarriage, among whom 240 patient had the pregnancy in IVF cycles (group I) and 200 women had a naturally way pregnancy (group II). The average age of patients was 33 years. Spectral karyotyping by fluorescent hybridization in situ on interphase nuclei of chorionic villi cells was performed with direct hybridization labeled with fluorescent dyes DNA probes. Results of cytogenetic and molecular cytogenetic studies showed that 43.33% abortions after IVF and 65.00% ones following natural conception had an abnormal karyotype, including autosomal trisomies respectively 35.00% and 42.00%; disomy X – 1.25% and 0.50%; monosomy X – 2.08% and 3.0%; monosomy 21 – 0.83% and 0.50%; polyploidy – 2.92% and 13.00%; structural chromosomal abnormalities – 0.83% and 4.0%; marker chromosome – 0.42% and 1.00%. Cytogenetic study of chorionic villi in recurrent spontaneous abortion is an integral part of the diagnostic evaluation. If at the cytogenetic study a spontaneous chromosomal anomaly detected, the next pregnancy proposed planning without a more detailed genetic examination. If a hereditary chromosomal anomaly, it is assessed the risk of its occurrence during the next pregnancy, carried out medical and genetic counseling. An artificial insemination with controlled selection of sperm and embryos in women with recurrent miscarriage history leads to a smaller number of chromosomal abnormalities in the embryo than in miscarriages after natural conception.
Additionally, women generally delay having a second child because of the overwhelming pressure in their lives. With the improvements in assisted fertility technologies in recent years, the number of elderly women attempting to bear children has increased. The quality of woman’s eggs and a man’s sperm declined dramatically with increasing age, leading to an increased risk of pregnancy-related complications among older women. Therefore, the types of fertility problems experienced by elderly females must be provided with considerable attention by obstetricians. This commentary article focuses on the medical problems faced by older second-child pregnant women. This work discusses their increased rates of infertility, spontaneous abortion, fetal malformation, gestational diabetes, cesarean section, placenta previa, postpartum hemorrhage, postpartum depression, and hypertensive disorders, which complicate pregnancy.
Spontaneous abortion occurs in 15-20% of clinically recognized gestations [ 1 ]. Genetic defects, especially chromosomal abnormalities, are the most common cause of spontaneous miscarriage during the first trimester; indeed, chromosomal abnormalities occur in approximately 60% of such cases [ 2 ]. It is unclear whether pregnancies conceived through assisted reproductive treatment (ART) are at an increased risk of pregnancy loss compared with naturally conceived pregnancies, when accounting for maternal age and ART procedures [ 3 – 5 ].
A retrospective cohort analysis was conducted using patients who were referred to the Genetics Laboratory of the Fertility Center of CHA Gangnam Medical Center from 2005 to 2009 following clinical abortion with subsequent dilatation and evacuation (D&E). Patients were grouped by the type of conception: conventional IVF, ICSI, and controls, which included nonviable spontaneous pregnancies from infertile couples who had not undergone ART and resulting from intrauterine insemination (IUI).
Thus, it remains controversial whether ART results in an increased risk of chromosomal abnormalities resulting in a first trimester miscarriage. The aim of this study was to evaluate the types and frequencies of chromosomal abnormalities occurring after different types of ART and to compare the outcomes for each ART group to those for a control group. Moreover, we compared the chromosomal abnormalities in miscarriages after ICSI according to infertility factors.
Zini A, Boman JM, Belzile E, Ciampi A: Sperm DNA damage is associated with an increased risk of pregnancy loss after IVF and ICSI: systematic review and meta-analysis. Hum Reprod. 2008, 23 (12): 2663-2668. 10.1093/humrep/den321.
The study protocol was approved by the Institutional Review Board of CHA Gangnam Medical Center.
Our results indicate that there is no risk increased chromosomal abnormalities due to ART, with the exception a greater number of chromosomal abnormalities in the ICSI group with male factor infertility. Therefore, these alterations could be correlated with the underlying parental risk of abnormalities and not with the ICSI procedure itself.
The genetic factor remains the most frequent cause of spontaneous abortions. Examination of the fetal tissue from spontaneous miscarriages shows that 75% of them were caused by abnormal karyotype. Other reasons, albeit rare, included submicroscopic genomic rearrangements, monogenic diseases, and polygenic inheritance disorders of the embryo. The aim of the study was to analyze the incidence of chromosomal aberrations in material from the miscarriage. The study included 47 samples of miscarriage material from 47 women. Fluorescent hybridization in-situ (FISH) was used for genetic examination. Chromosomal abnormalities were diagnosed in 72% of the samples, with trisomy 21 (25.5%), trisomy 16 (17%), and trisomy 18 (12.8%) as the most common. An abnormal number of copies of chromosome 18, 21, 22, indicating the coexistence of trisomy 18, 21, 22, was detected in 1 patient. It was another miscarriage in case of 14 subjects (29.8%). Chromosomal aberrations were diagnosed in the majority of fetal tissue samples from spontaneous miscarriages. More than one chromosomal aberration in a single embryo is an extremely rare occurrence. Miscarriage due to chromosomal aberrations occurred in the vast majority of women > 35 years of age.
Chromosomal abnormalities are the most common causes of abortion in the first trimester. Most miscarriages in this term of pregnancy are due to aneuploidy, the frequency of which is 50–80%. Autosomal trisomy is the most common chromosomal abnormalities. The aim of the study was to investigate chromosomal abnormalities of abortive material in women with recurrent spontaneous abortion after in vitro fertilization and after natural fertilization. Cytogenetic and molecular cytogenetic studies include 440 samples of chorionic villi from women with recurrent miscarriage, among whom 240 patient had the pregnancy in IVF cycles (group I) and 200 women had a naturally way pregnancy (group II). The average age of patients was 33 years. Spectral karyotyping by fluorescent hybridization in situ on interphase nuclei of chorionic villi cells was performed with direct hybridization labeled with fluorescent dyes DNA probes. Results of cytogenetic and molecular cytogenetic studies showed that 43.33% abortions after IVF and 65.00% ones following natural conception had an abnormal karyotype, including autosomal trisomies respectively 35.00% and 42.00%; disomy X – 1.25% and 0.50%; monosomy X – 2.08% and 3.0%; monosomy 21 – 0.83% and 0.50%; polyploidy – 2.92% and 13.00%; structural chromosomal abnormalities – 0.83% and 4.0%; marker chromosome – 0.42% and 1.00%. Cytogenetic study of chorionic villi in recurrent spontaneous abortion is an integral part of the diagnostic evaluation. If at the cytogenetic study a spontaneous chromosomal anomaly detected, the next pregnancy proposed planning without a more detailed genetic examination. If a hereditary chromosomal anomaly, it is assessed the risk of its occurrence during the next pregnancy, carried out medical and genetic counseling. An artificial insemination with controlled selection of sperm and embryos in women with recurrent miscarriage history leads to a smaller number of chromosomal abnormalities in the embryo than in miscarriages after natural conception.
Additionally, women generally delay having a second child because of the overwhelming pressure in their lives. With the improvements in assisted fertility technologies in recent years, the number of elderly women attempting to bear children has increased. The quality of woman’s eggs and a man’s sperm declined dramatically with increasing age, leading to an increased risk of pregnancy-related complications among older women. Therefore, the types of fertility problems experienced by elderly females must be provided with considerable attention by obstetricians. This commentary article focuses on the medical problems faced by older second-child pregnant women. This work discusses their increased rates of infertility, spontaneous abortion, fetal malformation, gestational diabetes, cesarean section, placenta previa, postpartum hemorrhage, postpartum depression, and hypertensive disorders, which complicate pregnancy.