So, basically neither the store information nor the game guide information is correct?
Repeated dosing does not increase the chance of twins or triplets and repeated dosing does not decrease the chance of having a baby?

I'm gonna make myself sound like a real addict here, but since I was updated to .05, I play 14 families. hehe (It started as a way for me to gather data on a lot of careers at one time, then I found myself unable to choose which of the little families to delete.) Out of those 14, I have one generation that had only 4 kids (this was a family created by my daughter) and one that had only 5 kids. All the remaining have had 6 kids per, and I'm striving to keep it that way. At the moment I have a couple in their 40s that have only 4 kids. They've already had baby boost and I'm getting nervous that they won't make 6 before they hit 50+ because they've recently had a few unsuccessful attempts. I've been tempted to try re-dosing them. Hence, my curiosity about everyone's experience with multi-dosing and it's effects.

Thank you all for your replies!