Serial progesterone measurement timed to the luteal phase and early pregnancy using CrMS Peak Day-referenced protocols reveals luteal insufficiency and early placental progesterone inadequacy that are associated with miscarriage risk and preterm labor. Progesterone supplementation guided by these standardized assessments has been associated with reduced pregnancy loss in NaProTECHNOLOGY-managed pregnancies, and the chapter details the specific drawing protocols, reference ranges, and supplementation decision thresholds used in clinical practice.
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Cite this article
Hilgers, T. W. (2004). Chapter 54: Assessing Progesterone During Pregnancy. The Medical and Surgical Practice of NaProTECHNOLOGY, 713-724.
Hilgers TW. Chapter 54: Assessing Progesterone During Pregnancy. The Medical and Surgical Practice of NaProTECHNOLOGY. 2004:713-724.
Hilgers, T. W. "Chapter 54: Assessing Progesterone During Pregnancy." The Medical and Surgical Practice of NaProTECHNOLOGY, 2004, pp. 713-724.
Hilgers TW, 2004·The Medical and Surgical Practice of NaProTECHNOLOGY
The sonographic ovulation classification is validated against targeted hormone profiles -- estradiol, LH, and serial post-Peak progesterone (P+3 through P+11) -- drawn at CrMS Peak-anchored time points rather than fixed calendar days. Hormone patterns corresponding to each sonographic category (e.g., absent LH surge in anovulation, progesterone rise without follicle rupture in LUF) confirm that ultrasound morphology reliably reflects the underlying endocrine disorder, establishing the biochemical legitimacy of the classification for clinical diagnosis.
Hilgers TW, 2004·The Medical and Surgical Practice of NaProTECHNOLOGY
A CrMS-synchronized hormone sampling protocol is detailed in which progesterone, estradiol, and other reproductive hormones are drawn at cycle-phase-specific time points defined by the charted Peak Day rather than by fixed cycle day, producing a targeted hormone profile that accurately reflects luteal and follicular function. This Peak Day-referenced approach substantially improves the diagnostic sensitivity for luteal phase deficiency, follicular dysfunction, and other endocrine abnormalities that fixed-day sampling routinely misclassifies.
Hilgers TW, 2004·The Medical and Surgical Practice of NaProTECHNOLOGY
Infertility is not merely a reproductive inconvenience but frequently signals systemic or hormonal pathology — including polycystic ovarian disease, endometriosis, thyroid dysfunction, and immune abnormalities — each carrying independent health risks beyond failure to conceive. Identifying and treating these underlying conditions reduces long-term morbidity and reframes infertility evaluation as a form of preventive medicine rather than a terminal bypass decision.
Bone HealthReproductive EndocrinologyFertility AwarenessNaProTECHNOLOGY
Hilgers TW, 2004·The Medical and Surgical Practice of NaProTECHNOLOGY
Chronic anovulation and progesterone or estradiol deficiency identified through CrMS charting represent periods of suboptimal bone accrual in women of reproductive age, because both estradiol and progesterone contribute to skeletal maintenance -- estradiol through suppression of osteoclast activity and progesterone through osteoblast stimulation. NaProTECHNOLOGY uses longitudinal CrMS records of ovulatory status and hormone profiles as a bone-health risk screen, guiding cycle-synchronized bioidentical hormone replacement to restore normal estrogen-progesterone balance and potentially mitigate progression toward osteoporosis in women with chronic cycle-based endocrine deficiencies.