Prometrium and Dark Brown Discharge: What to Know

Question
hello, I am 18, my last menstrual started on 06/27/05, and i have no children.  I went to me OB on 9/1/05 and we did an u/s and the baby showed 8wks 4d.  the fetal heartrate was at 168bpm. the doctor said everything looked really good. I have had 2 previous miscarriages, so he prescribed 200mg of prometrium to take vaginally everynite at bedtime, and 81mg of baby asprin. on 9/3/05 at 11:00am I was standing and felt something wet so I went to the restroom and there was like dark brown liquid all over my vaginal area and inner thighs, so I called the office but it was closed since it was Sat. but i got ahold of the nurse on call and she said it was probably nothing to go home and rest but i was sounding real concerned so she told me to go to the ER and they would do a sonogram on me so I could have piece of mind knowing that everything was ok. but when I went to the ER they didn't give me a sonogram they pulled tubes of blood and took urine sample did a pelvic exam and the doctor said my cervix was really tightly closed, so I don't know what to make of all of this.  The "spotting" only happened that 1 time and I had no kind of pain/cramps at all, it has stopped since. do you think everything is okay? your help deeply appreciated :)

Answer
At this stage of pregnancy it is common to have an occasional discharge of brownish blood. This is  "old blood" being pushed out of the uterus by the growing fetus. A sonogram at this time will show a fetus and a fetal heartbeat. Once you see the heartbeat, the risk of miscarriage drops to around 5% (from 15-20%). If there has not been further bleeding or discharge, don't worry about it.