This is the infamous Nash sponsored programme 'No More Brothers or Sisters', a US Government approved scheme for trusted corporations to gently introduce birth control to America.
The old gent is saying, "Now, Cynthia, you don't want any more brothers or sisters, do you? So give this handy rubbery thing to your mom -she'll know what to do with it - and you'll always only have your two sisters to complain about. Does that sound good? By the way, it's not something to wear, as your sister there has done. If you make a hole in it so it will hang off a button, it won't work and soon your house will be full of screaming k...., er, lots more children. OK?"
Cynthia replies, "It's a diaphram, isn't it? I can't take it, sir."
Old gent, "Why's that, Cynthia?"
Cynthia, "We're Catholics, sir."
Old gent, "Oh well, you may as well wear it then."