Insulin-like growth factor binding protein-3 in the detection of fetal Down syndrome pregnancies

Maternal serum IGF-I, IGFBP-1 and IGFBP-3 at 11-13 weeks in trisomy 21 and trisomy 18 pregnancies

OBJECTIVE

To investigate the possible value of maternal serum concentration of insulin-like growth factor-I (IGF-I), IGF binding protein-1 (IGFBP-1) and IGFBP-3 in first-trimester screening for fetal aneuploidies.

STUDY DESIGN

Maternal serum concentrations of IGF-I, IGFBP-1 and IGFBP-3 at 11-13 weeks of gestation were measured and compared in 30 trisomy 21, 30 trisomy 18 and 120 euploid pregnancies.

RESULTS

The median multiple of the normal median (MoM) values of maternal serum IGF-I, IGFBP-1 and IGFBP-3 in trisomy 21, trisomy 18 and euploid pregnancies were not significantly different (IGF-I: 1.10, 1.14 and 1.0 MoM, respectively; IGFBP-1: 1.10, 1.01 and 1.0 MoM; IGFBP-3: 0.90, 1.16 and 0.98 MoM).

CONCLUSION

Measurement of maternal serum IGF-I, IGFBP-1 and IGFBP-3 at 11-13 weeks of gestation is unlikely to be useful in screening for trisomies 21 and 18.

Human placental growth hormone is increased in maternal serum in pregnancies affected by Down syndrome

OBJECTIVE

To evaluate the relationship between maternal serum levels of human placental growth hormone (hPGH) and fetal Down syndrome at gestational midtrimester.

METHODS

We retrospectively analyzed samples of serum from 21 women with Down syndrome pregnancies detected at gestational midtrimester. The samples were obtained at 16-23 weeks' gestation during amniocentesis for fetal karyotyping. Sixty-two serum samples were used as controls, which were obtained at 16-23 weeks' gestation from women with singleton, uncomplicated pregnancies, who gave birth to healthy neonates with a birth weight appropriate for gestational age. The hPGH levels were measured by a solid-phase immunoradiometric assay using 2 different epitopes.

RESULTS

The median hPGH values in the serum of the Down-syndrome-affected pregnancies were significantly higher (p < 0.05) than those of the normal pregnancies at 16-23 weeks' gestation: the median value in the serum was 9.4 ng/ml (5th to 95th percentiles = 1.49-39.03) versus 4.7 ng/ml (0.53-7.88).

CONCLUSION

The hPGH levels in maternal serum were found to be higher at 16-23 weeks' gestation in pregnancies affected by fetal Down syndrome. Further investigation is needed to examine if maternal serum hPGH could be used as an additional marker in prenatal screening of Down syndrome at gestational midtrimester.