January 6, 2012:

Renovation work begins in building next to the Assisted Conception Unit.

May 2012: Pregnancy rates from ICSI fall to just in excess of 10%, but begin rising again until mid-July, when they exceed 45%.

September 2012: Pregnancy rates from IVF fall below 10%. At the same time, rates for ICSI fall below 25%.

November 6, 2012: GRI reports to the Human Embryology and Fertilisation Authority (Hefa) that treatment of five patients has been affected by "unexplained failed or reduced fertilisation rates".

The centre initiates full investigation but continues treatment.

November 8, 2012: Six more patients found to be affected by the same problem. Laboratory is shut down pending results of investigation and patients are transferred to Nuffield.

February 2013: GRI's in-house investigation is wrapped up without reaching a conclusion about what caused the drop.

March 28, 2013: Incident report by Hefa cites air contamination as a result of building works is the likeliest explanation for the fall and suggests fertility treatments may have been "adversely affected" as far back as May 2012.

November 2013: New licence is granted with storage-only conditions.

March 2014: New GRI fertility centre is due to open.