A state of 69 chromosomes, or three times the haploid number, most commonly caused by fertilisation of the egg with two sperm; the embryo that results can develop as far as a fetus, but is doomed to miscarry. The trophoblast of the placenta often undergoes partial changes of a hydatidiform mole. The noun form for this adjective is triploidy (the state of being triploid).

Abnormal conceptus in which there is coexistence of a hydatidiform mole with a fetus; caused by triploidy. Not as dangerous as a molar pregnancy without a fetus (see hydatidiform mole, complete), but medical follow-up is still necessary.

A multiple of the haploid number of chromosomes in a cell other than the normal diploid state. Includes triploid (three times the haploid number, or 69 chromosomes) and tetraploid (four times the haploid number, or 92 chromosomes). The noun form of this adjective is polyploidy (the state of being polyploid).