I don't have any personal experience. My youngest is almost 20 and I started Gleevec in 2012.
Here is a quote from a research study: Impact of Imatinib on the Fertility of Male Patients with Chronic Myelogenous Leukaemia in the Chronic Phase.
"One previous case report from our hospital confirmed the
present finding of the negative effects of imatinib on sperm
parameters in CML-CP patients. A male CML-CP patient
who had received imatinib treatment for 4 years, did not discontinue
imatinib treatment at the time of conception. This
patient exhibited a lower sperm survival rate (43.54%), and
reduced sperm activity (16.7%). However, he successfully
conceived, and a healthy baby was born after a normal pregnancy
. Follow-up on the baby was performed 36 months
after birth, and the results demonstrated that the baby grew
normally and remained healthy. Similar instances of the ability
of male CML patients to conceive during imatinib treatment
were reported, despite declines in sperm count, survival rate,
and activity [25, 26]. However, more clinical studies are needed
to evaluate the effects of imatinib on conception and fertility
in male CMP patients.
In summary, this investigation suggests that imatinib crosses
the blood-testis barrier and reduces sperm count, survival rates,
and activity in CML-CP patients. However, reproductive organ
structure and sex hormone levels were not affected. Future
studies should elucidate the mechanisms of imatinib penetration
of the blood-testis barrier and its effects on conception