Just an FYI:
pregnancy is NOT a illness. Unless you have a high risk pregnancy or pregnancy-related complications, doubtful you will find a physician who will say you can't travel just because you are pregnant unless late in the pregnancy (3rd trimester). This does not apply to OP (6 months or less).

If you CHOOSE to cancel because you don't want to travel while pregnant, why not purchase a cancel-for-any-reason travel insurance policy? Both you and your husband will have to purchase the insurance.