Maternal serum placental growth hormone, but not human placental lactogen or insulin growth factor-1, is positively associated with fetal growth in the first half of pregnancy.
OBJECTIVE
To investigate if maternal levels of human placental lactogen (hPL), placental growth hormone (PGH) and insulin-like growth factor-1 (IGF-1) are associated with growth rate of the biparietal diameter (BPD) in the first half of pregnancy.


METHODS
Data on 8215 singleton fetuses from the Copenhagen First Trimester Study with measurements of BPD from ultrasound scans performed at weeks 11-14 and 17-21 of pregnancy were analyzed. Growth rate was defined as millimeters of growth/day of BPD between the two scans. Fetuses with growth rate below the 2.5(th) centile (low growth rate, n = 203) and above the 97.5(th) centile (high growth rate, n = 203) were identified. As a reference group 212 fetuses with growth rate around the median were identified (intermediate growth rate). Out of the 618 selected cases in the three growth rate groups a total of 463 cases had a blood sample taken at the time of first-trimester ultrasound (5.6% of the original sample size of 8215 pregnancies). The maternal blood serum concentrations of hPL, PGH and IGF-1 were determined in the three different growth-rate groups. Linear regression analysis without adjustment and with adjustment for known and potential confounders was used to compare serum levels between the groups.


RESULTS
Simple linear regression showed a difference in serum level of log(10) PGH between the high and intermediate growth-rate groups (P = 0.037). When adjusted for maternal weight and crown-rump length, multiple linear regression analysis confirmed this difference, as fetuses with high growth rates had a 12% (95% confidence interval, 2-20%; P = 0.009) higher maternal serum level of PGH than those with intermediate growth rates. No differences in hPL and IGF-1 levels between the three different growth-rate groups were found after simple and multiple linear regression analysis.


CONCLUSIONS
Maternal PGH levels are higher in women carrying fetuses with high first-trimester growth rates than in controls, both in a simple unadjusted analysis and in analyses adjusted for known and potential confounders. Thus, PGH may be involved in fetal growth regulation as early as in the first trimester of pregnancy.
Pedersen
N G
NG
Department of Fetal Medicine and Ultrasound, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark. nina@ngpedersen.com
Juul
A
A
Christiansen
M
M
Wøjdemann
K R
KR
Tabor
A
A
D000328:Adult; D001724:Birth Weight / Q000502:physiology*; D005260:Female; D047109:Fetal Development / Q000502:physiology*; D005865:Gestational Age; D019382:Human Growth Hormone / Q000097:blood*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D010928:Placental Lactogen / Q000097:blood*; D011247:Pregnancy; D011261:Pregnancy Trimester, First
D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D010928:Placental Lactogen