A 42-year-old Braintree woman gave birth to a baby boy while standing on an inbound Red Line train yesterday morning, refusing help from stunned passengers who heard her moan and seconds later looked down to find her baby on the floor...

After the train left North Quincy, while crossing the Neponset River around 7:20 a.m., passengers reported hearing a muffled groan. Judge, dressed in a pink velour top and matching skirt, stood in the middle of the fourth car. Suddenly, her water broke.

''At first I thought someone spilled coffee, but it kept dripping,'' said Chin, 32. ''But she stood staring out the window ... I started doubting what I saw.''

About 90 seconds later, Chin said, ''I saw a head, then full baby fall out from her skirt, hit the floor sideways and slide the length of the doorway, stopping when he bumped up against the next row of seats. Still she stared out the window. Either she didn't know it happened or didn't want to acknowledge it.''

Judge bent down, picked up the baby and wrapped it in her scarf, Chin said.

As passengers slowly realized what had happened, witnesses said, the train rallied around the new mother. People offered sweaters and implored her to sit or lie down. Still, Judge refused.

''I'm fine,'' she repeated throughout the trip. ''I'm fine.''[...]

At one point, Judge took some nearby newspapers and placed them on the floor to soak up the blood. Some witnesses heard Judge apologize for the mess.

After leaving the train and heading for the stairs up to the station's main lobby, witnesses said, the placenta fell to the platform. Judge turned around, grabbed the afterbirth, put it in her shoulder bag, and headed upstairs.

''She just literally picked it up with her hand and put it in some kind of bag she was carrying, and this was in mid-stride ... It was the craziest thing I've ever seen,'' said Robert Busby, of Weymouth.[...]