Luteal phase defect by histological dating of endometrium among fertile women and unexplained infertile women :

The luteal phase of the human menstrual cycle reflects the functional lifespan of the corpus luteum (Baird et al., 1975). The corpus luteum is formed in response to the mid-cycle surge of luteinizing hormone from the remnants of the follicle following ovulation. It is the endocrine gland with the shortest lifespan , normally 14 ± 2 days, unless pregnancy occurs. The most important function of the corpus luteum is progesterone secretion .The LPD was defined by Jones (1949, 1975) as a defect of corpus luteum progesterone output either in amount or duration which results in inadequate stimulation of the endometrium for the implantation of the blastocyst. To be of clinical significance, LPD must be present in repeated cycles.Recently, attention has been focused on particular clinical situations in which the luteal phase defect occurs more frequently. These include hyperprolactinaemia, endometriosis, delayed ovulation, ovulation induction, proximal menstrual cycles after discontinuation of Danazol, the first 1 3 cycles after abortion, a full-term delivery or stopping the oral contraceptive,older women over the age of 35, administration of synthetic progestins, and aspiration of the pre-ovulatory follicle for oocyte recovery .The authers reported a problem incountered in diagnosing LPD as well as evaluating the reliability of the available diagnostic testes for this condition (Jordon et al, 1994, Soules et al ,1988 , Zhonghua ,1990 , (Annos et al, 1980; Rosenfeld et al ,1980; Balasch et al ,1982) .In light of the discomfort and inconvenience with the multiple endometrial biopsies needed to confirm the diagnosis of Luteal phase defect , investigators have attempted to identify alternative markers for the diagnosisof LPD including clinical presentation, BBT, serum progesterone assay, follicular size , endometrial markers and endometrial biopsy .Endometrial biopsy is taken using the Pipelle aspirator which is made of a clear, flexible ploypropylene sheath with an inner plunger. The device is well tolerated by patients and is easy to use. No external suction if required; the device is disposable. The Pipelle enables quick sampling of the endometrium (5-15 seconds of operating time), and the entire procedure can be accomplished within 10-15 minutes. A large meta-analysis examining the various devices for endometrial sampling reported the Pipelle to be the most sensitive technique (Bayer and DeCherney , 1993 ). The ideal time for taking endometrial biopsy depends upon the information that the infertility specialist is seeking . The optimal time to obtain an endometrial sample for confirmation of ovulation is on day 21-22. Timing of the procedure is critical when