Vietnam veterans who stated they had contracted malaria while in Vietnam had a higher estimated risk for fathering babies born with hypospadias. No associations between risks of defects and use of malaria chemoprophylaxis were found. The most important conclusion to be drawn from this study is that the data collected contain no evidence to indicate that Vietnam veterans have had a greater risk than other men for fathering babies with defects when all types of serious structural birth defects are combined. This study cannot prove that some factor associated with service in Vietnam was or was not associated with the occurrence of rare types of defects, defects in the babies of selected individuals, or defects in the babies of small groups of veterans. The conclusion, however, that Vietnam veterans in general have not fathered, at higher rates than other men, babies with defects when all types of birth defects are combined is based on relatively strong evidence.
All parents are at some risk of having a baby born with birth defects.
Assessing Vietnam veterans' risks associated with exposure to Agent Orange is difficult. The measures of exposure that can be obtained today are imperfect, at best. The ability of Vietnam veterans to give valid reports of exposure is unknown, and the records used for the assignment of EOI scores were made for military purposes, not for health studies. This limitation makes it particularly difficult to assess whether the few statistically significant associations found in this study between defects and greater opportunity for exposure to Agent Orange are likely to reflect true effects of exposure or whether they are merely chance occurrences. Moreover, the estimated relative risks for the exceptions presented here are rather low.