# Cancer and Pregnancy: Update of Estimates in Italy by Linking Data from Cancer Registries and Hospital Discharge Records

## TL;DR

This study updates cancer during pregnancy rates in Italy, showing rising live births and miscarriages but fewer abortions, with thyroid and breast cancers being most common.

## Contribution

The study provides updated population-based estimates of pregnancy-associated cancer in Italy using linked cancer registry and hospital discharge data.

## Key findings

- Pregnancy-associated cancer rate is 1.43 per 1000 pregnancies in Italy.
- Thyroid and breast cancers are the most common types during pregnancy.
- PAC rates increased for live births and miscarriages but decreased for abortions.

## Abstract

Cancer during pregnancy is a rare event which is becoming more frequent, partly due to women having children later in life. Managing pregnancy-associated cancer (PAC) is complex, as doctors must treat the mother while ensuring the baby’s safety. Historically seen as incompatible, recent evidence shows that many pregnancies can continue without harming the mother’s cancer outcome. This study provides an updated comprehensive analysis of pregnancy-related complications in women diagnosed with cancer, exploring both time trends and the impact of cancer on reproductive outcomes. Among 131,774 cases, 6329 had hospital access due to pregnancy, corresponding to a PAC rate of 1.43 per 1000 pregnancies, consistent with global trends. Thyroid and breast cancers were the most common. The study also found that PAC rates increased for live births and miscarriages but decreased for abortions. The findings of this study are crucial for healthcare planning and improving care for women with cancer in their childbearing years, particularly in relation to obstetric and reproductive health.

Background/Objectives: The increasing incidence of cancer during pregnancy is a growing public health concern, driven by delayed parenthood and rising maternal age. Pregnancy-associated cancer (PAC) presents complex clinical challenges, necessitating a balance between maternal cancer treatment and fetal safety. Historically considered incompatible with favorable pregnancy outcomes, evidence now suggests that pregnancy can often proceed without affecting cancer prognosis. A 2022 study in Italy provided the first population-based PAC estimates by linking cancer registries (CRs) and hospital discharge records (HDRs). This study aimed to update PAC estimates to 2019, covering 30% of the Italian population and addressing prior data limitations. Methods: A retrospective longitudinal analysis was conducted on women aged 15–49 diagnosed with malignant cancers between 2003 and 2019. Data from 21 Italian CRs were linked with HDRs to identify PAC cases, defined as obstetric hospitalizations occurring for women diagnosed with cancer in our study cohort in the period spanning from one year before to two years after a cancer diagnosis. All malignant cancers, excluding non-melanoma skin cancers, were analyzed. PAC rates were calculated per 1000 pregnancies, and trends were assessed using log-linear and JoinPoint regression models. Results: Among 131,774 women diagnosed with cancer, 6329 PAC cases were identified, with a PAC rate of 1.43 per 1000 pregnancies, consistent with global estimates. Thyroid (24.4%) and breast cancer (23.2%) were the most common. Analyzing the PAC rate by pregnancy outcome, in the period 2015–2019, this increased for both childbirths and miscarriages but decreased for voluntary terminations. Most hospitalizations (54%) occurred pre-diagnosis, peaking at diagnosis, especially for breast cancer (69%). Conclusions: PAC incidence is rising, particularly for live births and miscarriages, underscoring the need for multidisciplinary care and robust epidemiological insights to guide clinical management.