Harief Pearson, 22, his cousin Kydie McKenna, 22, and their 17-year-old accomplice attacked the young victim and kept her hostage for a number of hours in an attempt to abort her unborn baby.
The female assailants punched, stamped on and kicked the victim in her stomach, back and chest.
The girl also had one of her nails ripped off and alcohol was poured over her bloodied face.
During the attack, Pearson told the then 17-year-old victim, who cannot be named for legal reasons, that “it didn’t have to be like this”.
Part-way through the attack at a property in Harlesden on December 12 last year, Pearson also told his co-defendants, “I don’t think it’s dead yet, continue,” before leaving the room.
Despite the brutal attack, the victim did not suffer a miscarriage.
Pearson, McKenna and the teenage defendant – who cannot be named for legal reasons – were handed lengthy custodial sentences by Lady Justice Simler on Friday afternoon (July 5).
Pearson, of Newton Road, Brent, was sentenced to 11 years in prison, with a two-year extension.
He was also handed a 10-month jail term for perverting the course of justice, to run concurrently to the lengthier sentence.
McKenna, of Old Oak Lane, Park Royal, in Ealing received a 10-year prison term, with an extension of two years, for her part in the attack.
In addition, she received 6.5 years – to run concurrently – for a separate robbery offence and 8 months – to run concurrently – for perverting the course of justice.
The unnamed defendant, who is from the Hammersmith and Fulham area, was jailed for four years concurrently for administering a noxious substance, false imprisonment and attempted GBH.