Maine has explicit insurance guidance on transgender-related health care.

Statutes:

• 24-A M.R.S. § 4320-L (2019)
  Summary:

  Nondiscrimination.  An individual may not, on the basis of race, color, national origin, sex, sexual orientation, gender identity, age or disability, be excluded from participation in, be denied benefits of or otherwise be subjected to discrimination under any health plan offered in accordance with this Title. A carrier may not in offering, providing or administering a health plan:  

  A. Deny, cancel, limit or refuse to issue or renew a health plan or other health-related coverage, deny or limit coverage of a claim or impose additional cost sharing or other limitations or restrictions on coverage on the basis of race, color, national origin, sex, sexual orientation, gender identity, age or disability;

  B. Have or implement marketing practices or benefit designs that discriminate on the basis of race, color, national origin, sex, sexual orientation, gender identity, age or disability in a health plan or other health-related coverage;  

  C. Deny or limit coverage, deny or limit coverage of a claim or impose additional cost sharing or other limitations or restrictions on coverage for any health services that are ordinarily or exclusively available to individuals of one sex to a transgender individual based on the fact that the individual's sex assigned at birth, gender identity or gender otherwise recorded is different from the one to which such health services are ordinarily or exclusively available;

  D. Have or implement a categorical coverage exclusion or limitation for all health services related to gender transition;

  E. Otherwise deny or limit coverage, deny or limit coverage of a claim or impose additional cost sharing or other limitations or restrictions on coverage for specific health services related to gender transition if such denial, limitation or restriction results in discrimination against a transgender individual.

Bulletins and Announcements:

• Bulletin: Bulletin 437: Incorporation of the Affordable Care Act’s Consumer Protections into Maine Law
  Issued by: Maine Bureau of Insurance
  Issued on: July 23, 2019
  Summary:

  "Protections for transgender individuals include a prohibition against categorical coverage exclusions or limitations for all health services related to gender transition, and a prohibition against the arbitrary imposition of sex-specific or gender-specific coverage limitations or cost sharing."

Consumer Complaints: