I work in early childhood intervention, a federally mandated and state based program for kids under age three with developmental delays. As such I've seen more families of premature babies than you can imagine, and to count as premature in my program the baby needs to have been born before 27 weeks gestation. Most of the time we have no idea why the baby was born too early, research continues.
Recently a large British study has shown that women who underwent radiation therapy for cancer as children are at risk of having a premature or underweight baby.
Analysis of data from more than 10,000 female survivors also showed an increased risk of miscarriage in those who had radiotherapy to the abdomen.
The Birmingham University researchers said doctors should offer closer monitoring in these women. These researchers found the risk pf pre term delivery was increased three times and a low birth weight baby had twice the risk of women who had not had abdominal radiation.
No link was found between chemotherapy and pregnancy problems.
While it may seem like common sense this reinforces the idea that regardless of when you had your cancer treatment it needs to be shared with all of your medical providers. Like most other survivorship issues locating childhood cancer survivor support can be difficult. I recommend checking with young survivor sites such as I'm Too Young for This.