Chapter 35: Follicular and Luteal Phase Deficiencies: Advancing Concepts and New Terminology

Hilgers presents a refined classification of follicular and luteal phase deficiencies grounded in the integration of CrMS mucus pattern characteristics, cycle-phase-targeted estradiol and progesterone profiles, ultrasound folliculometry, and endometrial histology, introducing terminology that links specific chart signatures to defined endocrine subtypes and treatment protocols. Follicular deficiencies -- marked by short or poor-quality mucus phases and suboptimal estradiol -- and luteal deficiencies -- marked by a post-Peak phase under nine days, premenstrual spotting, or blunted serial progesterone curves -- are treated with tailored ovulation induction, cooperative progesterone replacement, and correction of contributing systemic disorders including thyroid dysfunction, hyperprolactinemia, and insulin resistance.