Heteromolecular Artimones (HMA)
Heteromolecular artimones (HMA) are hormone-like compounds whose molecular structure differs from the hormones the human body produces naturally. The term was coined by Dr. Thomas W. Hilgers as part of NaProTechnology, specifically to contrast with isomolecular hormones, which replicate endogenous molecular structure. Examples include norethindrone, medroxyprogesterone acetate, conjugated equine estrogens, and ethinyl estradiol: the active agents found in most oral contraceptives and many conventional hormone replacement formulations.1
Hilgers documented that the molecular difference between these compounds and endogenous hormones is not merely a matter of degree. Synthetic progestins bind progesterone receptors, but they also interact with androgen and glucocorticoid receptors in ways that endogenous progesterone does not. Conjugated equine estrogens and ethinyl estradiol differ metabolically and in tissue-specific activity from endogenous estradiol. These distinctions inform NaProTechnology's position that heteromolecular preparations and isomolecular preparations are not clinically interchangeable.2
NaProTechnology's clinical approach, as developed by Hilgers, does not use heteromolecular preparations in hormone replacement or pregnancy support. Cooperative progesterone replacement and cooperative estrogen replacement specify isomolecular compounds throughout. When oral contraceptives appear in NaPro clinical discussions, Hilgers applies this category label to their active agents to clarify why they fall outside NaProTechnology's therapeutic framework.3
The HMA designation matters for patients reviewing their medication history. A hormonal preparation that is heteromolecular will behave differently at the receptor level than one that is isomolecular, even if the two compounds are marketed for similar purposes. Clinicians practicing in the NaProTechnology framework distinguish between these categories when evaluating prior treatment history and planning restorative hormone support. and hormone replacement therapy.
Cited in this entry
- Williams WV et al. Hormonally Active Contraceptives Part I: Risks Acknowledged and Unacknowledged. Linacre Q. 2021. https://rrmacademy.org/library/hormonally-active-contraceptives-part-i-risks-acknowledged-and-unacknowledged-recrdkj7l2ft6afzf/
- Hilgers TW, Keefe CE, Pakiz KA. The Use of Isomolecular Progesterone in the Support of Pregnancy and Fetal Safety. Issues Law Med. 2015. https://rrmacademy.org/library/the-use-of-isomolecular-progesterone-in-the-support-of-pregnancy-and-fetal-safet-rec9gz3n4iplw6vym/
- Hilgers TW. The Medical and Surgical Practice of NaProTECHNOLOGY. Pope Paul VI Institute Press; 2004. https://rrmacademy.org/library/the-medical-surgical-practice-of-naprotechnology-rectiyuppdjrktphh/
This content is for educational purposes only and does not constitute medical advice. Consult an RRM clinician or healthcare provider for guidance specific to your situation.