Welcome to HCM,
At this time any type of cough
is to be prevented as it may increase abdominal pressure and it affects uterus
As there is blood in the cough you should evaluate your problem.
Consult physician and get investigated with CBC,ESR
and if unavoidable go for Xray chest and rule out any pathology like pneumonitis
Remain in cotact with your Obst.
Ok and bye.