Progesterone Levels During Ovulation and Luteal Phase
Condition: Infertility, Female
MeSH terms: Infertility; Infertility, Female
Study type: Observational

Summary: 
      Natural cycles are evaluated during fertility treatments for different therapeutic options,
      like insemination (IUI), time intercourse (TI) or frozen-thawed embryo transfers (FET). Two
      possible protocols can be used for natural cycles, with or without hCG trigger. Usually,
      studies including natural cycles consider both options as equivalent, not considering the
      possible bias that the exogenous hCG (human chorionic gonadotrophin) might have. In this
      prospective study, Investigators aim to evaluate the differences in the hormonal profile
      during the ovulation when it occurs spontaneously vs triggered with a bolus of hCG.
    

Detailed description: 
      For the pure natural cycle (PNC), ovulation will be detected by a combination of ultrasound
      monitoring the follicular growth and serial measurement of luteinizing hormone (LH),
      estradiol (E2) and progesterone (P4) levels, which is recognised to be the most accurate
      method of correctly identifying ovulation.

      For the modified natural cycle (MNC), a bolus of rhCG 6500 IU subcutaneous (sc) will be
      administered when 1 dominant follicle reaches 17mm or above, after excluding previous LH
      surge. This is the first prospective study where the differences on the hormonal profile for
      ovulation will be studied.

      HYPOTHESIS:

      H0: The hormonal profile is not different between the PNC and the MNC H1: The hormonal
      profile is different between the PNC and MNC

      Administration of hCG is a popular method for triggering ovulation since it may avoid the
      need to perform IUI or FET at weekends. However, it is an intervention compared with the
      detection of the spontaneous LH rise. Moreover, due to the presence of hCG receptors in the
      human endometrium, administration of hCG might interfere with endometrial receptivity.
      Previous publications evaluating pregnancy rates demonstrated that the use of hCG injection
      during the natural cycle reduces the pregnancy rates, in FET and IUI. It remains unclear what
      might be the mechanism to explain the lower pregnancy rates: a possible direct effect of hCG
      on the hCG receptors of the endometrium or a modification of the hormonal profile after the
      administration of the hCG, affecting the window of implantation (WOI).
    

Intervention name(s): human chorionic gonadotropin
Intervention type(s): Drug
Intervention description(s): once the dominant follicle reaches 17mm or above, a bolus of 6500 rhCG (Ovitrelle, Merck-Serono) will be administered subcutaneously
Other intervention name(s): Ovitrelle
Intervention MeSH terms: Chorionic Gonadotropin
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        healthy women with spontaneous ovulation
      
Biospecimen description: 
      serum
    
Keywords: luteal phase; natural cycle; human chorionic gonadotropin; progesterone; progesterone rise; ovulation