Sydney: There has been a 70 percent increase in cancers diagnosed during or soon after pregnancy, based on a study of 1.3 million births between 1994 and 2008. There has been no evidence of harm to babies.
The most common cancers detected were skin melanomas, breast cancer, thyroid and other endocrine cancers, gynaecological and lymphohaematopoeitic cancers.
The rate of pregnancy-linked cancer is increasing and is only partially explained by the rising number of older mothers, according to research led by the University of Sydney, BJOG: An International Journal of Obstetrics and Gynaecology reported.
The researchers say improved diagnostic techniques, detection and increased interaction with health services during pregnancy may contribute to the higher rates of pregnancy-associated cancer, according to a university statement.
The findings have been co-authored by Christine Roberts from the Kolling Institute at Sydney Medical School and Cathy Lee, Masters student in Biostatics at Sydney.
"The genetic and environmental origins of pregnancy-associated cancers are likely to pre-date the pregnancy but the hormones and growth factors necessary for a baby to develop may accelerate the growth of a tumour," Roberts said.
"Although this represents a 70 percent increase in cancers diagnosed during or soon after pregnancy, it is important to note that cancer remains rare affecting about two in every 1,000 pregnancies," Roberts said.
Although the age of the mother is a strong risk factor for cancer, increasing maternal age explained only some of the increase in cancer occurring.
The study also found that cancer during pregnancy was tied to a significantly increased risk of caesarean section.