Serum estradiol and progesterone assays vary substantially across laboratories because of differences in antibody specificity, calibration standards, detection platforms, and quality-control practices, meaning that a value within one laboratory's generic reference range may represent a clinically significant deficiency when interpreted against NaPro Peak-day-specific norms. NaProTECHNOLOGY requires consistent use of a single reference laboratory and interpretation relative to cycle-phase-specific NaPro standards rather than broad lab-generated reference intervals, to avoid missing subtle follicular or luteal phase defects that standard reporting would classify as normal.
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Cite this article
Hilgers, T. W. (2004). Chapter 23: Differences Between Laboratories. The Medical and Surgical Practice of NaProTECHNOLOGY, 281-284.
Hilgers TW. Chapter 23: Differences Between Laboratories. The Medical and Surgical Practice of NaProTECHNOLOGY. 2004:281-284.
Hilgers, T. W. "Chapter 23: Differences Between Laboratories." The Medical and Surgical Practice of NaProTECHNOLOGY, 2004, pp. 281-284.
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