Some aspects, e.g. selective reduction, are issues in the beginning of pregnancy controversy.

The obstetrician wasn't an expert in selective reduction, but she knew that with a shot of potassium chloride you could eliminate one or more.

He told me that he does a detailed sonogram before doing a selective reduction to see if one fetus appears to be struggling.

There's no doubt that selective reduction can improve the chances of survival for the remaining foetuses.

Of the 85 women undergoing selective reductions last year, 51 were reducing a pregnancy from twins to a single baby, up from 30 four years before.

"I would be surprised if multiple pregnancy through fertility treatment was not a significant component to the increase in selective reductions," he said.

Some day, the managers say, they will also use "selective catalytic reduction" to reduce nitrogen oxides.

This system reduces triple bonds faster than double bonds allowing for an especially selective reduction.

A more controversial technique, employed after there are multiple embryos or fetuses, is "selective reduction" to remove some.

Any reduction will be temporary assuming that the Commission comes up with proposals for a more selective reduction in a number of substantial budget lines.