Firsttrimester Diagnosis and Therapy @ 11 - 13 Weeks of Gestation - Part 1 : Guideline of the DEGUM, ÖGUM, SGUMGG, DGGG, ÖGG, Gynecologie Suisse, DGPM, DGPGM, BVF, ACHSE (AWMF S2e LL 085-002 1.1.2024) (https://register.awmf.org/de/leitlinien/detail/085-002).

This extensive AWMF 085-002 S2e-guideline "First Trimester Diagnosis and Therapy @ 11 - 13 of Gestation" has systematically analyzed high-quality studies and publications and the existing evidence (evidence tables) and produced recommendations (level of recommendation, level of evidence, strength of consensus). This guideline deals with the following topics in the context of the 11 - 13 weeks scan: the legal basis, screening for anatomical malformations, screening for chromosomal defects, quality assessment and audit, screening for preeclampsia and FGR, screening for preterm birth, screening for abnormally invasive placenta (AIP) and placenta accreta spectrum (PAS), screening for velamentous cord insertion and vasa praevia, screening for diabetes mellitus and LGA. Screening for complications of pregnancy can best be carried out @ 11 - 13 weeks of gestation.

The Fetal Posterior Fossa on Prenatal Ultrasound Imaging: Normal Longitudinal Development and Posterior Fossa Anomalies.

Fetal neurosonography and the assessment of the posterior fossa have gained in importance during the last 2 decades primarily due to the development of high-resolution ultrasound probes and the introduction of 3 D sonography. The anatomical development of the posterior fossa can be visualized well with the newest ultrasound technologies. This allows better knowledge of the anatomical structures and helps with understanding of the development of malformations of the posterior fossa.

Prenatal Detection of Chromosome Aneuploidy by Quantitative Fluorescence PCR.

Autosomal chromosome aneuploid pregnancies that survive to term, namely, trisomies 13, 18, and 21, account for 89% of chromosome abnormalities with a severe phenotype identified in prenatal samples. They are traditionally detected by full karyotype analysis of cultured cells. The average reporting time for a prenatal karyotype analysis is approximately 14 days, and in recent years, there has been increasing demand for more rapid prenatal results with respect to the common chromosome aneuploidies, to relieve maternal anxiety and facilitate options in pregnancy.

Prenatal detection of chromosome aneuploidy by quantitative-fluorescence PCR.

QF-PCR refers to the amplification of chromosome-specific polymorphic microsatellite markers using fluorescence-labelled primers, followed by semi-quantitative analysis of the products on a genetic analyser to determine copy number and/or imbalances of specific chromosomal material. This approach is now widely used for rapid prenatal diagnosis of the common trisomies. In addition, it can successfully detect maternal cell contamination and mosaicism in prenatal material.

Cystic periventricular leukomalacia in preterm infants: an analysis of obstetric risk factors.

Objective: To identify obstetric risk factors and to elucidate the effect of prolonged rupture of the membranes on the development of cystic periventricular leukomalacia (PVL) in preterm infants.

Methods: A retrospective case-control study of 95 preterm infants with the diagnosis of PVL and 245 healthy controls matched for gestational age. A total of 52 antenatal, intrapartum and neonatal characteristics were studied by univariate methods and logistic regression.

Prenatal detection of chromosome aneuploidy by quantitative fluorescence PCR.

Autosomal chromosome aneuploid pregnancies that survive to term, namely, trisomies 13, 18, and 21, account for 89% of chromosome abnormalities with a severe phenotype. They are normally detected by full karyotype analysis of cultured cells. The average reporting time for a prenatal karyotype analysis is approximately 14 days, and in recent years, there has been increasing demand for more rapid prenatal results with respect to the common chromosome aneuploidies, to relieve maternal anxiety and facilitate options in pregnancy.

Maternal urine for prenatal diagnosis--an analysis of cell-free fetal DNA in maternal urine and plasma in the third trimester.

Objectives: The aim of the study was the detection, quantification and correlation of cell-free fetal (cff) DNA in maternal urine and plasma in normal and complicated pregnancies during the third trimester.

Methods: One hundred and fifty-one urine and plasma samples obtained from 96 women carrying male fetuses, and 55 carrying female fetuses were collected and analyzed for cff-DNA using fluorescent PCR and quantitative real-time PCR. DNA was extracted from 1 mL maternal urine and analyzed with two different primer sets (SRY and DYS-14).

A prospective analysis of cell-free fetal DNA concentration in maternal plasma as an indicator for adverse pregnancy outcome.

Objectives: To evaluate whether cell-free fetal (cff) DNA in maternal plasma during the second trimester is a marker for developing pregnancy-associated complications. Two PCR techniques for the detection and quantitation of fetal DNA were compared.

Methods: Plasma samples were prospectively collected from 84 pregnant women carrying male fetuses before amniocentesis (14-29 weeks).

Fetal microchimerism is not involved in the pathogenesis of lichen sclerosus of the vulva.

Objectives: The aim of this study was to investigate a possible relationship between fetal cell microchimerism and lichen sclerosus of the vulva. We searched for the presence of male cells and DNA in vulval tissue samples.

Methods: Paraffin-embedded skin biopsy samples from 15 women affected with vulval lichen sclerosus who gave birth to at least one son were analyzed for the presence of microchimeric male cells using fluorescence in situ hybridization (FISH) and fluorescent PCR.

Fetal nucleated red blood cells in peripheral blood of pregnant women: detection and determination of location on a slide using laser-scanning cytometry.

Objective: The purpose of the study was to assess the feasibility of analysis of fetal nucleated red blood cells (NRBC) present in the maternal circulation by laser-scanning cytometry.

Methods: CD71-positive cells were obtained by magnetic cell sorting of peripheral blood of pregnant women after density centrifugation. Immunofluorescence for the Hbgamma-chain was combined with fluorescent staining of DNA (TO-PRO-3) and fluorescence in situ hybridization (FISH) with a Y-chromosome specific probe.

Rapid and simple prenatal diagnosis of common chromosome disorders: advantages and disadvantages of the molecular methods FISH and QF-PCR.

Molecular techniques have been developed for prenatal diagnosis of the most common chromosome disorders (trisomies 21, 13, 18 and sex chromosome aneuploidies) where results are available within a day or two. This involves fluorescence in situ hybridization (FISH) and microscopy analysis of fetal cells or quantitative fluorescence polymerase chain reaction (QF-PCR) on fetal DNA. Guidance is provided on the technological pitfalls in setting up and running these methods.

Detection and relocation of cord blood nucleated red blood cells by laser scanning cytometry.

Background: Fetal nucleated red blood cells (NRBC) present in the peripheral blood of pregnant women at low frequency are a potential target for noninvasive prenatal diagnostics.

Methods: CD71-enriched cells from male cord blood (CB) were stained for the gamma chain of HbF (Hb-gamma) and cytocentrifuged. Fluorescence in situ hybridization (FISH) was done for the Y chromosome.

Detection of maternal deoxyribonucleic acid in umbilical cord plasma by using fluorescent polymerase chain reaction amplification of short tandem repeat sequences.

Objective: Umbilical cord blood is a source of hematopoietic stem cells for transplantation. Although the first clinical applications have been encouraging, concern has been raised about contamination of umbilical blood by maternal cells, which might constitute a theoretical risk of graft-versus-host disease. The aim of this study was to assess the frequency of maternal deoxyribonucleic acid (DNA) contamination in umbilical cord plasma by using fluorescent polymerase chain reaction amplification of highly polymorphic short tandem repeat DNA markers.