**Appendix A**

In 2017, 28% of pregnant women between the age of 30 and 34 years, 9.92% between 35 and 39 years, 0.09% aged 40–49, and three women older than 50 years were diagnosed with breast cancer in Romania. Breast cancer (BC) remains a significant cause of death among Romanian women of fertile age (15–49 years), with a share of 8.8% in all causes of death in 2017. While the number of deaths caused by breast cancer declined by 19.42% between 1990 and 2017, the importance of the disease as cause of death increased by 38.51%. The incidence of BC in women of fertile age has increased by 39.44% between 1990 and 2017 with an average annual growth rate of approximately 1.24%. A substantial increase of BC was noted between 1990 and 1999 (26.70%), and between 2010 and 2017 (16.22%), although the number of deaths decreased by 4.95% between 2000 and 2009. BC prevalence also increased between 1990 and 2017, by 76.20%, or by 2.12% on average annually. Romanian women's age at first birth has increased between 1990 and 2019—from 22.3 to 27.4 years. Maternal age at birth has surged from 25 years in 1990 to 28.8 years in 2019, but the decade with the steepest increase was 1990–1999 (12%), followed by the 2000–2009 decade (7%) and the 2010–2019 decade (4.34%) with a similar trend in the incidence of BC.


**Table A1.** Estimated probability of PABC

EU—European Union, PABC—Pregnancy-associated breast cancer.

The estimated probability of pregnancy-associated breast cancer (PABC) is 1.29/100,000 among women aged 15–49 years in Romania, mainly due to pregnancy at an older age. We expect 59 new cases of PABC per year in Romania. Throughout the EU, we expect that 1568 women of fertile age may suffer from BC each year.

Data sets used for modeling the estimated probability of pregnancy-associated breast cancer (PABC) in Romania and throughout the EU were the following:

