German measles and birth defects

The link between rubella (German measles) in pregnant women and birth defects in their babies was not an easy one to find, because the disease can be relatively mild. After ophthalmologist Norman Gregg and others had suggested a link, the Australian statistician Oliver Lancaster was able to show that at the 1911, 1921 and 1933 Australian censuses there were peaks in the age distributions of deaf people, corresponding to a cohort born around 1899, when there was a known epidemic of rubella.

Lancaster also made an important discovery about sunlight and skin cancer.

Reference:

Lancaster, H. O. (1951) Deafness as an epidemic disease in Australia. British Medical Journal, 2: 1429-1432.