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 > IVM study


IVM study


A randomised controlled trial comparing In Vitro Maturation of oocytes with in vitro fertilisation in women with an increased risk of ovarian hyperstimulation syndrome.


Go to the IVM study website



Current ART requires COH to increase the number of oocytes. COH can lead to OHSS. In IVM immature oocytes are harvested from the ovaries without COH and matured in vitro in approximately 30 hours. These in vitro matured oocytes can be fertilised by IVF or ICSI. The first IVM-pregnancy was reported in 1991. It is estimated that since then over 1100 IVM children have been born worldwide.

In recent years the IVM technique has become increasingly effective. In observational studies the delivery rate of an IVM cycle was 10-15%. Due to the absence of COH IVM has a potential benefit for patients with an increased risk of developing OHSS, such as PCOS-patients. These potential benefits extend to patient friendliness and reduced costs.


Primary objective: To evaluate the cumulative live birth rate for two treatment strategies: 2 IVM/ICSI cycles versus 1 COH/IVF or COH/ICSI cycle.

Secondary Objectives: To evaluate the health and development of IVM/ICSI children versus COH/IVF/ICSI children in 5 years’ follow up program. To evaluate the number and nature of adverse events during or following the two treatment strategies. To evaluate the direct and indirect costs of the two treatment strategies. To evaluate patients’ quality of life during and after the two treatment strategies.


Study design
Multicentre randomised clinical trial in 400 couples. The trial will be preceded by a pilot study of 50 non-randomised IVM cycles for implementation of the technique.

Study population
PCOS patients indicated for IVF or IVF and ICSI patients who experienced an (imminent) OHSS in an earlier COH cycle.

Age between 18 and 38 years.


2 IVM/ICSI cycles or 1 COH/IVF or COH/ICSI cycle.


Outcome measures
Cumulative live birth rate after IVM/ICSI or COH/IVF/ICSI strategy.





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