Using frozen rather than freshly collected embryos during IVF treatment reduces the risks of stillbirth and premature delivery, according to three separate studies published yesterday. The findings, from the US, Finland and Australia, suggest the act of stimulating a woman's ovaries with powerful drugs and then collecting the extra eggs she produces temporarily disrupts any IVF attempt conducted shortly afterwards.

Interesting article there at The Guardian in the UK published today, coming on the heels of the one that Julia mentioned about egg freezing.

ETA I just realised I said eggs instead of embryos in the title. My brain's scrambled! I meant embryos.