The eCR specification says this in a few places related to pregnancy -
Published as part of C-CDA R2.1 Supplemental Templates for Pregnancy Status, Release 1 - US Realm

From what I can tell, that document seems to be withdrawn.
https://confluence.hl7.org/pages/viewpage.action?pageId=239215376

The withdrawal document points at the CCDA templates for Clinical Notes as the replacement.
https://www.hl7.org/implement/standards/product_brief.cfm?product_id=492

And this appears to be the new document in which the pregnancy templates live -
https://www.hl7.org/implement/standards/product_brief.cfm?product_id=494