Purpose: We describe a physiopathological model to the luteal insufficiency of infertile patients with mild/minimal endometriosis with normal hormone measurements in the early follicular phase.
Methods: We designed a case-control study with 24 patients, 14 fertile with in-phase endometrium (control group) and 10 infertile with mild/minimal endometriosis and luteal insufficiency (study group). The histologic dating of endometrium was performed during cycle days 23-25 and serum TSH, FSH, LH, prolactin, and estradiol levels were measured during the early follicular phase (cycle day 3). Progesterone serum levels were measured in three different occasions during the luteal phase.
Results: Patients with out-of-phase endometrium have lower estradiol levels (P = 0.031) and decreased progesterone secretion (P = 0.012) during the late luteal phase. Serum prolactin, TSH, FSH, and LH levels were similar between the groups (P > 0.05).
Conclusions: The physiopathology of luteal phase defect in infertile patients with mild/minimal endometriosis is associated with a small and large luteal cells dysfunction, characterized by abnormal follicular phase (lower estradiol serum levels) and lower progesterone LH-dependent secretion.