Extinction
Picture at some point in the near future, sentient self aware androids assisting then replacing the aging workforce as well as acting as carers, surrogate "children" for the childless etc.
It is entirely possible that humans may die out because the machines do their job too well, leaving the risk, expense and inconvenience of biological reproduction behind.
We are already seeing people choosing between having children and a career, some may eventually dispense with the former entirely in favor of one or more artificial life-forms with their shared experiences, memories and the capability to both mechanically replicate and self improve.
Its just possible, also a particularly virulent virus may wipe out the already reduced number of humans before anything can be done but the expected disruption of society would be more of a short term inconvenience to the Machines in much the same way as we regret the extinction of other species such as the dodo and passenger pigeon.
