Final answer:
The genotype of a pregnant woman with sickle cell disease is homozygous recessive, represented as 'ss'. This is because sickle cell anemia is an autosomal recessive disorder requiring two copies of the recessive allele for the full disease manifestation.
Step-by-step explanation:
The genotype of a pregnant woman with sickle cell disease is ss. Sickle cell anemia is an autosomal recessive disorder. This means that in order for an individual to have the disease, they must have two copies of the recessive allele, which in this case is represented by 's'. Individuals with one dominant (S) and one recessive (s) allele, denoted as Ss, have sickle cell trait which carries some symptoms but not full-blown sickle cell disease.
Individuals who are homozygous dominant (SS) will have normal red blood cells without any symptoms of the disease. Therefore, since the woman has sickle cell disease, her genotype must be homozygous recessive (ss).