I am so worried i will have another big baby, help?

To

I have 4 kids and expecting my 5th, my first 2 were normal size 7lb 6oz and 8lb 4oz but they were to my ex who was a smaller person (5 ft 5 and maybe 160lbs) my husband is about 5ft 11 and 240lbs and his daughter to his ex was 9lb 4oz c section and our babies were 10lb 7oz and 9lb 12oz. The reason i am worried about this bub being big is because of delivery. Ive had them all naturally but my 10lb 7oz one had shoulder dystocia and it took 25 minutes to deliver her shoulders. It was a medical emergency and the worst experience ever. I was overdue 2 weeks. My last was 9lb 12oz and while the birth was easy i went overdue 2 weeks before being induced again and ended up with a hairline fracture of my tailbone. I didn't have diabetes with any of them but i am so scared of shoulder dystocia. I am 21 weeks measuring 25 weeks already, my stomach is already huge like im 30 weeks and ive been eating so healthy it doesnt seem to matter what i do i have big babies. Do you think its worth asking to be induced on my due date or earlier? do you think theyll do it? i dont wanna get to 42 weeks again and i refuse to try castor oil