I am sorry to hear of your losses in the past Shell.
I know clomid is prescribed for a variety of reasons including hormone dysfunction and luteal phase defects. If your pregnancys miscarried early then clomid might help however when you have miscarried further into your pregnancy then I don't see how it would help. But I am no expert.

I know women with luteal phase defects (less then 10days from ovulation to AF) If you conceive with a luteal phase defect, you have a greater chance of the pregnancy ending in miscarriage.

This next bit comes from a website which I have included at the bottom.

Clomid helps to make the luteal phase of normal length by increasing the production of progesterone, which is the hormone that helps to maintain the uterine lining, thus helping to maintain a pregnancy.

Read more: Clomid and Fertility

GL I am sure your specialist has his reasonings and I hope it helps you carry your baby/s to term.