{
  "abstract": "Background The organisation of oocyte retrival presents significant challenges for both clinicians and patients. Methods such as the use of oral contraceptives prior to stimulation adversely affect outcomes. Our objective was to determine if a longer pretreatment with oestradiol for flexible oocyte retrieval scheduling affects the results of ovarian stimulation in patients requiring in vitro fertilisation (IVF).Methods This retrospective, descriptive, cohort study included 194 women recruited from an academic affiliated private infertility clinic in Mexico. Patients requiring IVF treatment were pretreated with oestradiol before undergoing ovarian stimulation as standard care in our centre. The short group (group A, n=98) included patients in whom oral oestradiol was withdrawn 2 or 3 days after initiating menstruation, while the extended group (group B, n=96) included patients who used oestradiol until 4–8 days after starting menstruation.Results The clinical pregnancy rate was comparable between groups B and A, at 65.6% and 57.1%, respectively, with relative risk (RR) 1.15 (95% CI 0.92 to 1.44, p=0.2412). The implantation rate was not significantly higher in group B than in group A (40.1% vs 34.2%), with an RR of 1.17 (95% CI 0.81 to 1.70, p=0.4566). The numbers of oocytes retrieved, metaphase II oocytes, fertilised oocytes and embryos transferred, and the miscarriage and live birth rates did not significantly differ between the two groups.Conclusions Administration of oestradiol in a long regimen during luteal phase does not have a deleterious effect on ovarian stimulation. Moreover, it provides a scheduling alternative that is convenient for both patients and the medical team.",
  "authors": [
    {
      "affiliations": [
        "Instituto de Ciencias en Reproducción Humana, Leon, Mexico",
        "División de Estudios de Posgrado, Universidad Nacional Autonoma de Mexico Facultad de Medicina, Ciudad de Mexico, Mexico"
      ],
      "name": "María Cristina Lanuza-López"
    },
    {
      "affiliations": [
        "Instituto de Ciencias en Reproducción Humana, Leon, Mexico"
      ],
      "name": "Patricia Cancino-Villarreal"
    },
    {
      "affiliations": [
        "Instituto de Ciencias en Reproducción Humana, Leon, Mexico"
      ],
      "name": "Claudia González-Ortega"
    },
    {
      "affiliations": [
        "Instituto de Ciencias en Reproducción Humana, Leon, Mexico"
      ],
      "name": "Antonio Martín Gutiérrez-Gutiérrez"
    },
    {
      "affiliations": [
        "Instituto de Ciencias en Reproducción Humana, Leon, Mexico",
        "Instituto de Ciencias en Reproducción Humana del Sureste, Mérida, Mexico"
      ],
      "name": "Raul Eduardo Piña-Aguilar"
    }
  ],
  "title": "Use of oestradiol in luteal phase to improve scheduling of ovarian stimulation in infertile patients treated with in vitro fertilisation",
  "uid": "d8abe42b-8fc4-5d52-9f13-476a0e466a34"
}