Collins became known to viewers in her native Mexico as a reporter of “Televisa 24 horas” (1974), Noticiero con Jacobo Zabludovsky. In 1979 Collins was sent by Televisa as their first correspondent in California where she began as a general assignment journalist also covering baseball in the Major Leagues with the San Diego Padres and the Los Angeles Dodgers, job she did until 1986. Later that year was transferred to Spanish International Network (SIN) the network later named Univision. In eighteen years in Univision Network Collins was well known for her job as a Mexico Correspondent, Texas Correspondent, and International Correspondent. In 1993 was appointed as the successor of María Celeste Arrarás as the weekend anchor of Noticiero Univision, covering Jorge Ramos and María Elena Salinas while they were out. In 2000 was named Senior Correspondent for the news magazine “Aqui y Ahora” position that with Noticiero Univision fin de semana hold it until she left the network in August 2005.

In 1999 María Antonieta convinced her friend Juanita Castro, the younger sister of Fidel and Raúl Castro, to co-write and publish Juanita’s autobiography in Spanish edition: My brothers Fidel and Raúl, the secret story. The book was finally published in October 2009.

Collins underwent plastic surgery in 2004 and has spoken extensively about it.

In an article in People en Español (March 2008), Collins announced that she would be leaving Telemundo when her contract expired in August 2008 and that she wished to return to anchoring news.