A new reports on the risks of exposure during pregnancy to a supplement, diethylstilbestrol (DES), that is linked to a rare cancer. The study found that DES-exposed patients with clear-cell adenocarcinoma had ‘increased mortality across their life span.’ For women aged 10 to 34 with DES-related clear-cell adenocarcinoma, the risk of death was 27 times higher than for other US women in that age group.