[–] jobes 0 points (+0|-0)

So the article mentions injecting subjects with Mycobacterium vaccae. From the wiki:

Mycobacterium vaccae is a nonpathogenic species of the Mycobacteriaceae family of bacteria that lives naturally in soil

I think a better study might be to not inject people with this, but to have the pregnant women spend more time outdoors. It's almost as if humans never evolved to live in sterile environments and require a constant intake of various bacteria to strengthen us.