Serum triple-marker screening in in vitro fertilization and naturally conceived pregnancies

Objective: To establish a reference distribution of maternal serum alpha-fetoprotein (AFP) at 11–13 weeks’ gestation and define the contribution of maternal variables that influence the measured concentration of AFP. Methods: Serum concentration of AFP at 11–13 weeks was measured in 1,500 singleton pregnancies which were not complicated by hypertensive disorders or diabetes mellitus and resulted in the live birth at or after 37 weeks of phenotypically normal neonates with birth weights above the 5th and below the 95th percentile. Multiple regression analysis was used to account for maternal characteristics that influence the measured concentration of AFP and a distribution of log multiples of the median (MoM) values was fitted. Results: Log₁₀ AFP increased with gestational age, decreased with maternal weight and was significantly affected by maternal racial origin, smoking status and method of conception. Compared with values in Caucasian women who were non-smokers and conceived spontaneously, AFP MoM was on average 23% higher in Afro-Caribbeans and 8% lower in East Asians, 11% higher in smokers and 10% higher in those conceiving by in vitro fertilization. Conclusion: In normal pregnancies at 11–13 weeks, serum AFP increases with gestational age and is affected by maternal race, weight, smoking status and method of conception.

Section: Discussionmentioning

confidence: 99%

Maternal Serum Alpha-Fetoprotein in Normal Pregnancy at 11–13 Weeks’ Gestation

Bredaki

Wright²,

Akolekar³

et al. 2011

“…An improved method with a detection rate of about 60% of affected pregnancies was the combination of maternal age with second trimester maternal biochemistry [Orlandi et al, 1997]. However, studies on maternal serum screening for aneuploidy in IVF pregnancies reported reduced AFP and elevated HCG concentrations, leading to a higher than expected positive screening rate [Frishman et al, 1997;Ribbert et al, 1996]. Recently, this observation was confirmed for ICSI pregnancies too [Lam et al, 1999].…”

Section: Possible Applications Of Noninvasive Techniques Of Prenatal mentioning

confidence: 99%

Is Intracytoplasmic Sperm Injection Itself an Indication to Perform Preimplantation Genetic Diagnosis (PGD)?

Ludwig¹,

Geipel²,

Berg³

et al. 2001

Intracytoplasmic sperm injection (ICSI) provides the only sufficient treatment to overcome severe forms of male infertility. However, male infertility is linked to several genetic problems as an increased number of chromosomal aberrations, cystic fibrosis transmembrane conductance regulator gene mutations, Y-chromosome microdeletions, and androgen receptor mutations. Therefore, these couples are at a higher risk of transmitting genetic problems to their offspring compared to the general population. A proposed increased number of gonosomal aberrations in the offspring possibly results from the ICSI technique itself. This led in general to a worldwide agreement to counsel those couples to undergo invasive prenatal diagnosis in order to exclude chromosome abnormalities, especially gonosomal aberrations. In this paper the genetic risks of these couples and the possible implications of ICSI itself are discussed. Preimplantation genetic diagnosis may be considered a procedure of choice in these cases, but substantial ethical problems arise when such a screening is sought. An alternative procedure of prenatal diagnosis in these couples seems to be ‘genetic sonography’, i.e. high-resolution ultrasound with measurement of nuchal translucency at the end of the first trimester, and detailed fetal evaluation at 18–22 weeks of gestation.

“…In ART pregnancies maternal serum marker levels change during the first trimester affecting the risk assessment for DS [5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26]. Counseling for prenatal screening of women carrying an ART pregnancy is complicated due to contradictory reports in FTS performance in ART pregnancies.…”

Section: Introductionmentioning

confidence: 99%

“…Counseling for prenatal screening of women carrying an ART pregnancy is complicated due to contradictory reports in FTS performance in ART pregnancies. Several studies reported higher false-positive rate (FPR) compared to spontaneously conceived pregnancies [5,6,7,8,9,10,11], some studies found higher FPR even after correction for maternal age [12,13,14,15] and others reported similar FPR [16,17,18,19,20]. Whether the prevalence of fetal chromosomal abnormalities in ART pregnancies is different from naturally conceived pregnancies is however unclear.…”

Section: Introductionmentioning

confidence: 99%

Validation of Correction Factors for Serum Markers for First-Trimester Down Syndrome Screening in Singleton Pregnancies Conceived with Assisted Reproduction

Engels¹,

Pajkrt

Groot³

et al. 2013

Objective: To validate previously computed correction factors for free β-human chorionic gonadotrophin (fβ-hCG) and pregnancy-associated plasma protein-A (PAPP-A) in in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) pregnancies with hormone treatment and to determine the effect on false-positive rate (FPR). Methods: Retrospective study on 249 IVF and 250 ICSI cases and 20,190 controls. Correction factors 1.42 (PAPP-A), 1.17 (fβ-hCG) in IVF; 1.56 (PAPP-A) in ICSI were applied on the absolute serum concentrations. Analysis was done on log₁₀-transformed multiples of medians (MoMs). Results: In the controls, mean PAPP-A and fβ-hCG MoM were 1.004 and 1.062. Before correction, mean PAPP-A MoM was significantly lower in IVF (0.757; p < 0.001) and in ICSI (0.671; p < 0.001) and after correction comparable (1.071; p = 0.053 in IVF; 1.048; p = 0.178 in ICSI). Before correction, mean fβ-hCG MoM was comparable (1.054; p = 0.59 in IVF and 1.051; p = 0.56 in ICSI) and after correction significantly higher in IVF (1.241; p < 0.001). After correction the likelihood for receiving a false-positive result was 1.03 in IVF pregnancies (95% CI 0.98-1.09; p = 0.248) and 1.02 in ICSI pregnancies (95% CI 0.97-1.07; p = 0.448). Conclusions: After correction the FPR in IVF and ICSI pregnancies with hormone treatment reduces to the observed FPR in the controls.