After the premiere at the 2017 Toronto International Film Festival, director Dan Gilroy and Denzel Washington decided to re-structure and re-focus parts of the narrative, which resulted in the removal of 12 minutes of footage. The director said, that the TIFF premiere served more as "a very high end test screening," because there was no time to do it before, and all involved are now happy with the final cut. [Oct. 2017]
At one point Roman mentions to Maya that he was a "forceps baby", to which Maya jokes that she was too, immediately thereafter admitting that she was only kidding. Given what is shown of Roman's social disorders, it is likely that he was not kidding. A forceps birth was one in which the child's body became stuck, for whatever reason, and to assist the birthing process the obstetrician used forceps (something like large clamps) to grip the child by the skull and quite literally yank the child out - albeit one would hope with some finesse and care. The procedure has fallen into disfavor, as some experts say that the use of forceps around a baby's skull can cause brain damage and lead to all manner of psychological or mental disorders.
The trivia item below may give away important plot points.
Roman claims to be able to use Uber in one scene, which may seem incompatible with the flip phone that he was seen to own previously. But this occurs after his lifestyle change, and the implication is that he has obtained a smart phone -- or at least some means of accessing Uber.