Influence of medically assisted reproduction techniques on crown-rump length and biochemical markers of trisomy 21 in the first trimester of pregnancy

There appears to be a small difference in CRL development between spontaneous pregnancies and pregnancies conceived by assisted reproductive technology (ART). Specific ultrasonographic curves for pregnancies conceived by ART would be more relevant and precise. The underlying pathophysiological mechanisms are not very clear and offer possibilities for future research.