If a Black woman is pregnant by a White man then she can not get pregnant by a black mam while she is pregnant by a white man
Excluding the weird claim that a woman can have twins by 2 different men
If White men have higher IQ then black men
Then White men getting black women pregnant with their consent would help improve the average IQ of society
But black men getting white women pregnant would lower the average IQ of society
As a general trend with some exceptions
Most African Americans have White Gentile & or Ashkenazi Jewish & or Sephardic Jewish ancestry
Ashkenazi & or Sephardic Jews traded & owned slaves in and to the United States of America
Slavemasters had children with their slaves