The official CDC website says that they found it definitely did cause intussusception:
"The results of the investigations showed that RotaShield® vaccine caused intussusception in some healthy infants younger than 12 months of age who normally would be at low risk for this condition. The risk of intussusception increased 20 to 30 times over the expected risk for children of this age group within 2 weeks following the first dose of RotaShield® vaccine."
See http://www.cdc.gov/vaccines/vpd-vac/rotavirus/vac-rotashield.... Now, that's not much of an increase in absolute terms because intussusception is relatively rare, but so is infants dying due to rotavirus infection in the US - the estimates I'm seeing are 20-60 deaths a year without vaccination. Even a relatively rare adverse reaction is enough to outweigh the benefits of the vaccine in the US.
Now, you're right that the clinical trials "detected no statistically significant serious adverse effects". That's because they were so small that, even though the adverse reactions were common enough to outweigh the benefits, they couldn't actually detect them as being statistically significant. Hell, even if the vaccine was somehow hypothetically killing ten times as many babies as would've died from rotavirus, I don't think the trials used to approve the vaccine could have detected that. That's kind of worrying.
"The results of the investigations showed that RotaShield® vaccine caused intussusception in some healthy infants younger than 12 months of age who normally would be at low risk for this condition. The risk of intussusception increased 20 to 30 times over the expected risk for children of this age group within 2 weeks following the first dose of RotaShield® vaccine."
See http://www.cdc.gov/vaccines/vpd-vac/rotavirus/vac-rotashield.... Now, that's not much of an increase in absolute terms because intussusception is relatively rare, but so is infants dying due to rotavirus infection in the US - the estimates I'm seeing are 20-60 deaths a year without vaccination. Even a relatively rare adverse reaction is enough to outweigh the benefits of the vaccine in the US.
Now, you're right that the clinical trials "detected no statistically significant serious adverse effects". That's because they were so small that, even though the adverse reactions were common enough to outweigh the benefits, they couldn't actually detect them as being statistically significant. Hell, even if the vaccine was somehow hypothetically killing ten times as many babies as would've died from rotavirus, I don't think the trials used to approve the vaccine could have detected that. That's kind of worrying.