Human-assisted reproductive technologies (ART) are a widely accepted treatment for infertile couples. At the same time, many studies have suggested the correlation between ART and increased incidences of normally rare imprinting disorders such as Beckwith-Wiedemann syndrome (BWS), Angelman syndrome (AS), Prader-Willi syndrome (PWS), and Silver-Russell syndrome (SRS). Major methylation dynamics take place during cell development and the preimplantation stages of embryonic development. ART may prevent the proper erasure, establishment, and maintenance of DNA methylation. However, the causes and ART risk factors for these disorders are not well understood.
Results
A nationwide epidemiological study in Japan in 2015 in which 2777 pediatrics departments were contacted and a total of 931 patients with imprinting disorders including 117 BWS, 227 AS, 520 PWS, and 67 SRS patients, were recruited. We found 4.46- and 8.91-fold increased frequencies of BWS and SRS associated with ART, respectively. Most of these patients were conceived via in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), and showed aberrant imprinted DNA methylation. We also found that ART-conceived SRS (ART-SRS) patients had incomplete and more widespread DNA methylation variations than spontaneously conceived SRS patients, especially in sperm-specific methylated regions using reduced representation bisulfite sequencing to compare DNA methylomes. In addition, we found that the ART patients with one of three imprinting disorders, PWS, AS, and SRS, displayed additional minor phenotypes and lack of the phenotypes. The frequency of ART-conceived Prader-Willi syndrome (ART-PWS) was 3.44-fold higher than anticipated. When maternal age was 37 years or less, the rate of DNA methylation errors in ART-PWS patients was significantly increased compared with spontaneously conceived PWS patients.
Conclusions
We reconfirmed the association between ART and imprinting disorders. In addition, we found unique methylation patterns in ART-SRS patients, therefore, concluded that the imprinting disorders related to ART might tend to take place just after fertilization at a time when the epigenome is most vulnerable and might be affected by the techniques of manipulation used for IVF or ICSI and the culture medium of the fertilized egg.
Vettori D et al., 2015·Journal of Neonatal-Perinatal Medicine
Aplasia cutis congenita (ACC) is rare skin disorder of newborns that has been linked to both assisted reproductive technology (ART) and feto-reduction procedures. ACC is characterized by well-demarcated lesions that are devoid of all skin layers. Group-V ACC presents with a distinctive and symmetrical distribution pattern. It is thought to result from an insult to the fetus after concomitant twin demise and is almost exclusively reported in monochorionic gestations.A 41-year-old female with an in vitro fertilization (IVF) assisted tri-chorionic gestation subsequently underwent selective feto-reduction of Fetus C. The patient delivered two pre-term neonates secondary to pre-eclampsia. The initial exam of Twin B showed extensive, well-demarcated, symmetrical areas devoid of any skin over the anterior and lateral trunk, extending up the lateral thoracic walls. Chest and abdominal viscera were visible through a thin fibrous membrane. The skin defects were managed conservatively with twice-daily dressings of Aquaphor, and Vaseline gauze. The areas of aplasia slowly contracted, though residual scarring was noted. After four weeks in the NICU, most of the areas were healed.ACC in multi-fetal pregnancies is a rare, but well-described complication. This is, to our knowledge, the first reported case in a tri-chorionic IVF gestation after feto-reduction. With increased incidence of ART-associated pregnancies and the use of feto-reduction for higher order gestations, this may become more common. Neonates often require specialized intensive care. Conservative management usually will suffice, although surgical grafting may be required. Physicians should be aware of this condition and counsel their feto-reduction patients of the risk.
Uyar A et al., 2014·Current Opinion in Obstetrics & Gynecology·
Open Access
Purpose of reviewGenomic imprinting refers to preferential allele-specific gene expression. DNA methylation-based molecular mechanisms regulate establishment and maintenance of parental imprints during early embryo development and gametogenesis. Because of the coincident timing, a potential association between assisted reproductive technology (ART) procedures and imprinting defects has been investigated in various studies. In this review, we provide an overview of genomic imprinting and present a summary of the relevant clinical data. Recent findings: ART procedures affect DNA methylation pattern, parental imprinting status, and imprinted gene expression in the mouse embryo. In humans, several case series suggested an association between ART and imprinting disorders, with a three-fold to six-fold higher prevalence of ART use among children born with Beckwith-Wiedemann syndrome compared to the general population. However, more recent studies failed to support these findings and could not demonstrate an association between imprinting disorders and ARTs, independent of subfertility. ART procedures may affect methylation status of imprinted regions in the DNA, leading to imprinting disorders. Although the low prevalence of imprinting disorders makes it challenging to perform conclusive clinical trials, further studies in large registries are required to determine the real impact of ARTs on their occurrence.
The aim of the article was to investigate the relationship between pregnancy complications, infertility and assisted reproductive technologies (ART). The study was conducted on 1331 couples with complicated reproductive history. It is found that miscarriage and other complications of pregnancy depend rather on the etiopathogenesis of infertility than on the technique of ART. The highest frequency of complications of pregnancy was diagnosed in women with endocrine disorders. In case of congenital malformations in the fetus the frequency of birth defects was 3.6% after in vitro fertilization (IVF) and 1.8% in case of spontaneous pregnancy. It was found an increased risk of birth defects in singleton boys conceived by IVF.