Partly because it’s so physically taxing, relactation is not common. (Medication is often also involved.) But over the past few weeks, online forums focused on relactation have been swarmed with newly vaccinated mothers like Ms. Koltes. Some had stopped breastfeeding their children more than a year earlier. “I’m glad I’m not the only one here trying to relactate for this reason!” one woman wrote in a lively thread in a private Facebook group... The answer, six researchers agreed, is that newly vaccinated mothers are right to feel as if they have a new superpower. Multiple studies show that their antibodies generated after vaccination can, indeed, be passed through breast milk. As with so much to do with the coronavirus, more research would be beneficial. But there is no concrete reason for new mothers to hold off on getting vaccinated or to dump out their breast milk, they said.