Pregnancy-associated cancers: frequency and temporal trends in Italy.

Objective: Limited data are available on the frequency and time trends of pregnancy-associated cancers, particularly from Southern European countries. The aim of this study was to analyze the frequency and time trends of pregnancy-associated cancer in Italy.

Methods: This was a population-based linkage study using the regional hospital discharge forms database of four Italian regions with more than 17 million inhabitants. All resident women with a hospital discharge form reporting a birth or abortion in the time period under consideration were identified. The time period of the study was 2003-2015 for the Piemonte and Puglia region, 2006-2015 for the Tuscany region, and 2005-2015 for the Veneto region. Risk of developing a pregnancy-associated cancer was calculated as the ratio of the number of pregnancy-related cancers to the total number of pregnancies.

Results: A total of 2 297 648 pregnancies were identified. Overall, the pregnancy-associated cancer frequency was 134.8 per 100 000 pregnancies: the frequency ranged from 127.1 in Puglia to 157.3 in Tuscany. The frequency for 100 000 pregnancies was 66.4 in women aged <30 years; the risk increased with age, with a frequency of 275.6 among women aged 40+ years. Approximately two-thirds of cancers were associated with pregnancies resulting in a delivery and one-third with pregnancies resulting in a termination of pregnancy or spontaneous pregnancy loss. No clear trend emerged in the risk of pregnancy-associated cancer per 100 000 pregnancies and calendar year.

Conclusion: No clear time trend was observed in the frequency of pregnancy-associated cancers in Italy during the last 10 years, the rates being 104, 164, and 130 per 100 000 pregnancies, respectively, in 2003, 2010, and 2015.