I always like to point out that when congress banned the transatlantic slave trade in 1808, it didn't stop the desire of slaveholders for new slaves.
Enslaved women were used as brood mares until they physically could not produce more children. Then some of those women were subjected to medical experimentation (without painkillers) to repair the damage caused by pregnancies either too frequent or too early.
The population of enslaved black people quadrupled in the 50 years after the transatlantic slave trade was banned. White slave owners would often rape their enslaved women, and then sell off the children for profit. And could get more profit, because the children had lighter skin.
Oh, and that ban on the transatlantic slave trade? That was very easy to get around. Jim Bowie, as an example, used to smuggle slaves from French pirate slaver traders into the US through the swamps of Louisiana. Then he moved to Texas as part of a plan to turn it into a slave holding nation. (Mexico had actually banned slavery)
Jim Bowie, died at the Alamo, likely in bed shitting himself from cholera. Couldn't have happened to a more deserving sort.