In Combined First-trimester Down Syndrome Screening, the False-positive Rate is Not Higher in Pregnancies Conceived After Assisted Reproduction Compared with Spontaneous Pregnancies

The maternal serum levels of pregnancy-associated plasma protein-A (PAPP-A) were reduced in hormonally stimulated pregnancies in the in vitro fertilization and intracytoplasmic sperm injection groups (N=176; PAPP-A: 0.82) and in the entire assisted reproduction group (N=282; PAPP-A: 0.83) as compared with controls (N=24,783; PAPP-A: 0.94). However, the false-positive rate of first-trimester combined screenings was not statistically significantly increased in assisted reproduction pregnancies after adjustment for maternal age.