We can assume until proved otherwise that Fallujah birth defects are due to DU

Useful list of DU sites.

It is clear that there is an increased incidence of birth deformities in Fallujah.
What is causing it? The candidates are Depleted Uranium (DU), White Phosphorus, something else, or a combination of the above.

We know that White Phoshorus was used.
Abu Sabah, a refugee from Fallujah, reported seeing phosphorus bombs: "They used these weird bombs that put up smoke like a mushroom cloud. Then small pieces fell from the air with long tails of smoke trailing behind them. These exploded on the ground with large fires that burnt for half and hour," Abu Sabah said. "When anyone touched these fires their bodies burnt for hours." Source

However, White Phosphorus, although toxic , is not known to cause birth deformities. Absence of evidence is not evidence of absence, but it is not a major candidate.

Malnutrition, particularly folic acid deficiency, is a known cause of neural tube defects, but not of the more complex defects being seen in Fallujah.

There is controversy over  DU was used in Fallujah. It is hotly denied by Richard S Lowry, a "military historian" who has written a book on Fallujah.

Others disagree:
Having seen what appeared to be a depleted uranium (DU) missile fired at a building in Fallujah on CNN during the first week of the fighting, AFP asked the Pentagon if DU weapons are being used in Fallujah. "Yes," Lt. Col. Joe Yoswa said, "DU is a standard round on the M-1 Abrams tank." Source.
That quote again:
Christian Bollyn of the American Free Press , Washington D.C asked Lt.Col. Joe Yoswa if the US was using Depleted Uranium in Fallujah and received the reply that " DU is the standard round on the M-1 Abraham Tanks" which have been used in Fallujah. source

The source continues,

It was estimated that during that assault over 10,000 tons of depleted uranium, DU, was used in the bombardment of the city of 300,000 people. Both the Pentagon and the British governments insist that the use of DU is not illegal. Source 
This 10,000 tonne figure is doubtful. It may relate to the amount used in Iraq as a whole - see below. 

ICBUW is investigating the possible use of uranium weapons during the attacks on Fallujah. Currently it seems that Abrams tanks and Bradley fighting vehicles were deployed during both battles. Both vehicles carry armour piercing rounds containing uranium and high explosive rounds which do not. However the fact that they were not facing armoured targets does not mean that only high explosive rounds were used. In fact, there are indications that armour piercing ammunition may be more effective against individuals fighting behind cover in urban areas. While is not known how widespread the use of uranium weapons was during the fighting, it seems likely that it was used to some extent.
Source

The Pentagon admits to having used 1,200 tonnes of DU in Iraq thus far.
Source

So there are wide discrepancies in the reportage. These discrepancies can be resolved by publication of the original the ammunition lists from 2004. Or let's hear from crews who were there. Most importantly, let us do a survey on the ground in Fallujah, to find out what radiation counters and chemical analysis shows.

Here is one source that could prove Lowry wrong:
Mr. Rasheed presented a video report entitled "Witness from Fallujah." And regarding DU, he said: "We detected abnormally high radioactivity by using a Geiger counter." Source.

DU is both radioactive and chemically toxic. As a chemical weapon it would be banned by the Geneva Convention, so the military have no choice of stance except Stout Denial. There is no proof that DU causes these problems, they say, exploiting journalists' ignorance of the fact that there is no proof in science, only evidence. And the evidence that DU causes problems is as widespread as the use of these weapons.


There is evidence that DU can cause birth deformities.: "In aggregate the human epidemiological evidence is consistent with increased risk of birth defects in offspring of persons exposed to DU."


What is lacking is not "proof", but the willingness of politicians to listen to doctors rather than to generals in matters relating to medicine.

The evidence needs sorting out, and the Bradford Hill guidelines need to be applied.