Yes, pregnancy can be achieved with embryos of quality D. However, the possibilities are too low.
The Association for the Study of Reproductive Biology (ASEBIR) establishes morphological criteria for the classification of embryos according to their quality. Grade D embryos are considered to be of poor quality and have low, but not zero, implantation rates.
Whenever possible, quality A and B embryos should be transferred before grade C or D embryos.
Read the full article on: Classification criteria and categories according to the embryo quality ( 75).

Marta Barranquero Gómez
Graduated in Biochemistry and Biomedical Sciences by the University of Valencia (UV) and specialized in Assisted Reproduction by the University of Alcalá de Henares (UAH) in collaboration with Ginefiv and in Clinical Genetics by the University of Alcalá de Henares (UAH).