OBJECTIVES: To evaluate the relationship between nuchal translucency (NT), nuchal fold thickness (NFT), gestational age, and maternal age in fetuses with normal karyotype determined by amniocentesis or subsequent healthy infant. METHODS: NT and NFT had been routinely measured in our clinic during 54 pregnancies with normal karyotype documented either by amniocentesis or the birth of on healthy infant. NT and NFT measurements at various gestational and maternal ages were compared using student’s t – test. RESULTS: NT measurements increased with advancing gestational age. Increase in NT values between 11 and 12 – 13 and between 12 and 13 weeks’ gestation were statistically significant (p=0.09, p=0.002, and p=0.008, respectively). Both NT and NFT tended to decrease with increasing maternal age. CONCLUSION: Although NT ≥ 3 mm and NFT ≥ 6 mm are generally considered abnormal, gestational and maternal age have effects on these cut-off values. Different cut-off values for NT and NFT might be considered for different maternal age groups. Largescale investigations are needed to evaluate these cut-off values.
Keywords: gestational age, maternal age, nuchal folds thickness, nuchal translucency