These centres can often seem like a resource for women considering or in need of abortions, but many are just fronts for anti-abortion activists who use deceptive tactics to persuade women to remain pregnant. Some of these clinics even receive taxpayer funding.
Crisis pregnancy centres manage to "stop just short of the line" where they would be regulated as legitimate healthcare providers, which allows them to get away with what Oliver called "emotional manipulation," "coercive" behaviour and outright "bullshit."
After exposing the groups on Sunday's broadcast of "Last Week Tonight", Oliver then announced that he was going to run his own tax-exempt crisis pregnancy centre.
In 2015, Oliver opened his own church called Our Lady of Perpetual Exemption. Now he's created Vanned Parenthood, a service of his new organisation, Our Lady of Choosing Choice, which is, as the name implies, a van.
Oliver also brought out "Wanda Jo Oliver" (aka comic, actress and "SNL" alum Rachel Dratch) to show exactly what the new mobile operation was legally allowed to get away with.
"I tell women if they get an abortion, it'll make a ghost baby that'll haunt their hoo-ha forever!" Dratch declared. She also noted that she's not even required to have any training to operate the van's ultrasound machine.
"This is all perfectly legal and there is absolutely nothing stopping us from parking outside an abortion clinic tonight and haranguing people in the morning," Oliver said. "And frankly, there really f**king should be."
Check it out in the clip above.