Value of Follicular Flushing. Randomised Controlled Trial
Condition: Infertility
MeSH terms: Infertility; Flushing
Study type: Interventional

Summary: 
      The purpose of this study is to evaluate whether the addition of follicular flushing to the
      initial aspiration during oocyte retrieval increases the number of oocytes retrieved in women
      undergoing ovarian stimulation.
    

Detailed description: 
      There is an ongoing debate regarding the effectiveness of follicular flushing during oocyte
      retrieval. Currently published studies and metanalyses suggest that follicular flushing does
      not improve live birth rate, clinical pregnancy rate or the number of oocytes retrieved.
      However, currently published studies may be confounded by the types of needle used,
      aspiration pressures, number of times flushing is repeated, etc. Additionally, follicular
      flushing should be examined in specific patient populations according to their response to
      ovarian stimulation.

      In the current study, each woman will have one ovary (right or left) randomly assigned to be
      aspirated with or without the addition of follicular flushing. This study design ensures that
      clinical and demographic characteristics of the couple will not affect the outcomes
      evaluated. The primary endpoints will be the number of oocytes retrieved per ovary assigned
      to each group. Secondary outcomes will be the oocyte recovery rate (oocytes retrieved per
      follicle aspirated) oocyte maturation rate, fertilization rate, and embryo development per
      ovary assigned to each group.

      The study population will include three subgroups according to observed ovarian response to
      ovarian stimulation (poor responders, normal responders, hyper responders). Assuming a
      minimum clinically significant difference in oocyte yield of 1 oocyte, a sample size of
      twenty patients per subgroup is required to yield 80% power.

      Patients aged <43 years with the presence of at least one follicles >11mm in each ovary on
      the day of triggering final oocyte maturation will be eligible for inclusion in the study. 60
      patients (20 in each of the aforementioned subgroup) will be recruited and just prior to
      oocyte retrieval their left and right ovaries will be randomly allocated into flushing or the
      no-flushing group. In both ovaries all follicles greater than 11mm will be punctured by the
      same 16G double lumen needle, using the same aspiration pressure. In the flushing group,
      flushing will be performed up to a maximum of five times or until a cumulus oocyte complex
      (COC) is retrieved.

      In the control group all follicles greater than 11mm will be aspirated by the same double
      lumen needle and no flushing will be performed.

      All COCs will be grouped according to the ovary they originated from by the embryologists and
      their development will be recorded until Day 3 following fertilization (Number of MII
      oocytes, number of fertilized oocytes, number good quality Day 3 embryos).
    

Intervention name(s): Experimental: Follicular aspiration with addition of follicular flushing.
Intervention type(s): Procedure
Intervention description(s): Follicular flushing if necessary up to 5 times using a double lumen needle for oocyte recovery
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Follicular Flushing; Oocyte Retrieval