This claim is false; biologically, a child as young as 10 years old can get pregnant. It is indeed a rare occurrence for a young child to get pregnant. Pregnancy can only occur if the individual is ovulating, which, according to the NHS, can start as early as the age of 10. However, pregnancies at the age of 10 can have many birth issues and negative outcomes. The University of Maryland School of Medicine states that through their research on the 90,000 deliveries of individuals between the ages of 10 and 19. They found that the younger the pregnant individual is, the higher the risk of complications. "We found 10- to 13-year-olds had a 56 percent higher risk of preterm delivery and a 32 percent higher risk of cesarean delivery compared to those ages 14 to 17,”(Goodman). To conclude, it is possible for a ten-year-old to get pregnant. However, it has too many risks and connections to abuse.  
https://www.medschool.umaryland.edu/news/2022/youngest-girls-who-get-pregnant-have-highest-risk-of-poor-outcomes-study-finds.html
https://www.nhs.uk/conditions/periods/fertility-in-the-menstrual-cycle/