AG&M annual report 2017

AG&M Science Impressions 2017
Jonneke Hollanders and Martijn Finken
at around 6 weeks postpartum. Cortisol and cortisone
concentrations were determined in the entire strand of
hair from the neonate at birth, and in the centimeter
closest to the scalp from the hair of the neonate at
6 weeks postpartum as well as both the maternal
hair strands.
We found that neonatal cortisol levels, but not
cortisone levels, directly postpartum as well as at
the OPV were correlated to maternal cortisol levels
(P5 times
higher than maternal levels, with a decrease of ±50%
between birth and the OPV for cortisol, while cortisone
levels remained stable. Since GC concentrations were
still increased compared to maternal levels at the
OPV 6 weeks postpartum, hair GC concentrations at
this time point appear to reflect both the intra- and
extrauterine period. Directly postpartum and at the
OPV, most perinatal and maternal factors were not
associated with neonatal GC levels, or only weakly,
such as birth weight in kg (but not SDS), perinatal
infection and caesarian delivery. However, a striking
positive association was found between neonatal GC
levels postpartum and gestational age, which was also
present when the analyses were repeated with only
term subjects. This seems to be a reflection of the
increase in cortisol concentrations during the third
trimester, a phenomenon that might be caused by a
positive feedback loop due to corticotrophin-releasing
hormone production by the placenta. This positive
feedback loop is thought to promote fetal organ
maturation, and might also play a part in the induction
of labor. Although the specifics of hair growth in utero
are still largely unclear, it is likely that at least the third
trimester is reflected in neonatal hair. Therefore, GCs
measured in neonatal hair might be a useful tool to
assess the intrauterine environment, which allows us to
increase our understanding of the developing HPA axis.
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