FSTL1 is expressed in the human placenta, mainly in extravillous trophoblasts.
Basal FSTL1 protein expression is low in villous trophoblasts, but is increased in hypoxic conditions.
FSTL1 expression in trophoblasts is regulated by post-transcriptional mechanisms.
There is no evidence of expression of the miR-198 passenger miRNA in trophoblasts, or for its effect on FSTL1 expression.