iam 37 yrs old and iam 5 weeks 2 days pregnant,i had miscarriege 2 months back when I was 4 wks and 4 days preggo. Otherwise am healthy no co-morbids. I never had any miscarriege or pregnancy before that. I have regular 28 day cycle. This time I had cramping on and off and I have to go to school for which I have to take 30 min train ride and then have to walk 15 minutes oneway three to four days per week. Is it okay to do this actvity in early pregnancy and also I have to sit in class almost 8 hrs three days a week,will it affect my baby .....