in states without such positive laws in effect or in any state prior
to passage of such laws, would Bob somehow lose parental rights to his
relevant offspring upon conviction for the rape, as an automatic
matter of course, and without any special application by Alice for the
judicial proactive right-termination order?
There are cases in states without special laws where rapists have been granted parental rights over children born to women they raped as a result of the rape. This is the default rule.
The state could bring a separate civil action to terminate Bob's parental rights. (Unlike other civil actions related to juveniles, this one comes with a right to a jury trial and a right to a lawyer at state expense if the defendant cannot afford one, and often an intermediate burden of proof like clear and convincing evidence.) But it would not be at all a foregone conclusion that his parental rights would be terminated in such a case if he fought the termination of parental rights.
Normally, parental rights can only be terminated for conduct harmful to the child directly and not for conduct harmful to the mother. In a rape case, there is rarely evidence of direct harm to the child born as a result of the rape.
Typically, the best grounds for terminating his parental rights would be that he would incarcerated for so many years after being convicted that he was incapable of providing for the child's needs and would inevitably engage in what legally amounted to child neglect as a result. But this would be resolved on a case by case basis by the judge under standards that were far from clear on the correct resolution of the case.
Alice would often not even have standing to bring an action against Bob to terminate his parental rights, as many states reserve the authority to bring such lawsuits for the state. She could seek to minimizing his parenting time and parental responsibilities. But, again, Alice would face an uphill battle in doing so.
Rape related pregnancies are not all that uncommon according to the U.S. Center for Disease Control: "Almost 3 million women in the U.S. experienced RRP during their lifetime." This is about one in six women who have been vaginally raped in their lifetime according to the CDC.
Wikipedia notes that:
Recent estimates suggest that rape conception happens between 25,000
and 32,000 times each year in the U.S. . . .
The Rape, Abuse and Incest National Network, a charity based in
Washington, D.C., reached a much lower figure calculated using
estimates from the Justice Department's 2005 National Crime
Victimization Survey. The network took that survey's annual average of
64,080 rapes committed in 2004 and 2005 and applies the 5 percent
pregnancy rate to reach an estimate of 3,204 pregnancies a year from
From the same Wikipedia source:
A 1996 study of thousands of US women showed that, of pregnancies
resulting from rape, 50% were aborted, 12% resulted in miscarriage,
and 38% were brought to term and either placed for adoption or raised.
But this issue still comes up one to ten thousand times per year in the United States depending upon the estimates relied upon. This is small compared to the 3,661,220 children born in the United States in 2022, but is still a not insignificant number.