At the Mass Archives they have on microfilm the BMD index for the years 1915-1970. They also have on microfilm the Mormon film for Boston births for the years to 1955(I think that was the end year) I found my cousins father's name - my aunt was unwed. For some reason when my cousin was born(in Boston) the father's name was listed on the Mormon film but if you look on the Mass. index the father's name is blank and when I went to Mass Vitals to see actual record, I was just curious, they wouldn't let me look at it because it was sealed. If you can get to the Archives it would be worth a shot.