They do stop having babies, but you can still improve their parenting skills. I swear I get skill points faster just having them kiss repeatedly and interrupting any walks to the love shack, which is just fluff anyway as the deed is done with a kiss alone. Within about five minutes I had 2 old geezers who were Master Parents! Not sure it works that well with all of them as some seem to master things faster than others, but I have managed several elders this way without losing the services of the women for 2 years at a time.
I got my First Esteemed Elder and Jack-of-All-Trades this way. (Or should I say "Jane"-of-All-Trades? Was a woman.) When I reached my first population stop at 17, I got tired of getting her to constantly tell stories to the children to build up the Parenting Skill. She was a runner, so it was hard to find her. So I set her preferred skill to Parenting and ignored her for awhile.
Later, when one of my Founder Women reached 50, I did that trick, kiss, grab, kiss, grab, etc., etc. After about a minute or so, it said "Esteemed Elder".