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Follikel diameter studie

Timing of hCG administration according to predetermined criteria of follicular size

Go to the Follikel diameter webpage
For randomisations go to the Follikel diameter website

After the introduction of GnRH agonists for controlled ovarian hyperstimulation (COH) in In Vitro Fertilisation and embryo transfer (IVF-ET), the duration of follicular growth was no longer restricted by the anticipation of a premature LH surge (Porter el al 1984). It became possible to schedule final oocyte maturation and subsequent oocyte retrieval, not according to follicle size, but according to the convenience of patients and doctors. True evidence, however, whether the moment of inducing final oocyte maturation in the follicular phase or not, is crucial in order to achieve good pregnancy rates, was not sought thoroughly. Arbitrarily criteria have been used for administering hCG.

Our objective is to explore whether timing of hCG according to predetermined criteria of follicular size leads to higher ongoing pregnancy rates in GnRH agonists down-regulated COH IVF-ET cycles.

Study design
A randomised clinical trial.

Women undergoing IVF or ICSI, aged between 18 and 43 years and who have an indication for IVF or ICSI treatment according to the Dutch NVOG guidelines are eligible for the trial. The patients may only participate for one treatment cycle (a first or second cycle). Stratification will be performed according to IVF or ICSI treatment and first or second cycles.

Intervention and follow-up
Standard GNRH agonist long luteal protocol combined with recombinant FSH daily of 50, 150, 225 IU subcutaneously, and (1)hCG 10.000 IU administration, subcutaneously, as soon as the leading follicle measures 18 mm3 ( 1mm3) for final oocyte maturation, or (2) hCG administration as soon as the leading follicle measures 22 mm3 ( 1mm3).
Oocyte retrieval will be performed 36 hours after hCG administration.Embryo-transfer is started 72 hours after oocyte retrieval. Lutealphase support is started at the evening after oocyte retrieval.Follow-up is one completed IVF/ICSI treatment cycle or in case of pregnancy: untill ongoing pregnancy.

Outcome measures and analysis
Primary: ongoing pregnancy rates, secondary: total days of controlled hyperstimulation, total amount of rFSH used, thickness of double layer endometrium in mm, total number of metaphase II oocytes (ICSI only), total number and quality of oocytes (IVF only), fertilization rate, total number and quality of embryos, cleavage stage morphology, number of embryos suitable for cryo-preservation, OHSS (threatened), biochemical and clinical pregnancy rate.
Analysis will be performed according to intention to treat principle.Efficacy parameters: x2, student t-tests and ANOVA will be used to compare groups.
A total of 400 patients will be entered in order to prove or refute a difference of 13% in ongoing pregnancy-rate over a control rate 25% with a power of 80% and an alpha of 0.05.

Participating hospitals
Academic Medical Centre Amsterdam, Onze Lieve Vrouwe Hospital Amsterdam, Tergooi Hospitals Blaricum, Rijnstate Hospital Arnhem, Medisch Spectrum Twente Enschede.

Patienten informatie (Word)
Follikel diameter protocol (Word) - versie 14-12-06