I don’t know this for sure but here’s my best guess based on some personal experience and quick google searches:

• MA state law requires employer to allow Parental Leave which is unpaid and lasts minimum 8 weeks. Wife will be eligible if she’s worked there more than 3 months. She needs to notify HR at least 2 weeks prior to absence.
• If her employer does not offer her paid maternity leave (which you’re saying is the case), she should apply for Paid Family Medical Leave (PFML). This is a state program that is different then FMLA (which is a federal program she probably is ineligible for since working less than 12 months).

If HR gives her a hard time about taking leave, you can post on r/legaladvice and you may get more help.