Maternal serum concentrations of human placental lactogen, estradiol and pregnancy specific beta 1-glycoprotein and fetal growth retardation.

Background: To determine if maternal serum levels of human placental lactogen (hPL), estradiol, and pregnancy-specific beta 1-glycoprotein (SP1) measured at approximately 18 weeks' gestation were associated with fetal growth retardation (FGR) in infants delivered at or after 37 weeks.

Methods: Serum samples were obtained at a mean of 18 weeks' gestational age from 200 multiparous women with risk factors for FGR. Maternal serum concentrations of hPL, estradiol and SP1 were correlated with FGR.

Results: A total of 59 (29.5%) of the 200 infants were diagnosed postnatally with FGR. There were no significant differences in the prevalence of FGR among the lowest quartiles of estradiol, hPL or SP1. However, pregnancies in the highest quartile of estradiol levels at 18 weeks' (> 580 pg/ml) were associated with a significantly lower risk of FGR than those in the lower three quartiles, 8 out of 50 (16%) vs 51 of 150 (34%) (p = < 0.05). The prevalence of FGR associated with the highest quartile of hPL (> 1.73 micrograms/ml) was 12.2% compared to 35% in the lower three quartiles (p = 0.025) and the prevalence of FGR associated with the highest quartile of SP1 (> 43 ng/ml) was 14% compared to 34.7% in the lower three quartiles (p = 0.018). Only one out of 21 infants (4.5%) whose mothers had each value in the highest quartile of hPL, estradiol, and SP1 was diagnosed with FGR compared to 58 out of 178 (32.6%) of the remaining infants (p = 0.007).

Conclusions: In pregnancies of women at high risk for FGR, higher levels of estradiol, hPL, and SP1 at 18 weeks are associated with a decreased prevalence of FGR. This finding indicates that high levels of these hormones are related to a lower risk of FGR, but that low levels do not predict FGR.