"Although numerous animal experiments and some human data show potent effects of cocaine on the central nervous system, we were unable to detect any difference in Performance, Verbal or Full Scale IQ scores between cocaine-exposed and control children at age 4 years."

Source

Hurt, H., Malmud, E., Betancourt, L., Braitman, L. E., Brodsky, N. L., & Giannetta, J. (1997). Children with in utero cocaine exposure do not differ from control subjects on intelligence testing. Archives of pediatrics & adolescent medicine, 151(12), 1237–1241. doi.org/10.1001/archpedi.1997.02170490063011