Pregnancy and neonatal outcomes following malignancy in pregnancy at a tertiary care Canadian center: a retrospective chart review.

Objective: Data on pregnancy-associated cancers (PACs) are lacking. The objectives of this study were to determine the incidence of PACs and describe the characteristics and outcomes of pregnancies affected by malignancy at a single tertiary care center in Ottawa, Canada. Methods: This was a retrospective chart review of individuals with PAC at The Ottawa Hospital (TOH) between 2011-2022. Eligible cases were identified from the TOH Data Warehouse, the TOH instance of the Better Outcomes Registry & Network Ontario, and the TOH Division of Maternal Fetal Medicine's Perinates database. Chart reviews were conducted to confirm case eligibility and to extract demographic, oncologic, obstetrical, and neonatal measures. The annual incidence of PAC over the 11-year period was reported per 1000 deliveries. Descriptive statistics were used to describe the sample, including frequency (n) and proportions (%) for categorical variables and mean and standard deviation (SD) for continuous variables. Results: The final cohort included 59 individuals with PAC at TOH between 2011-2022. The annual incidence of PAC ranged from 0.47 to 1.54 per 1000 deliveries. The most common PACs were breast cancer (28.8%), Hodgkin lymphoma (10.2%), and thyroid cancer (8.5%). Common interventions during pregnancy included chemotherapy (33.9%) and surgical intervention (32.2%). A total of 19 individuals (32.2%) did not undergo PAC-related treatment during pregnancy. There were 55 livebirths (91.7%), 2 spontaneous abortions (3.3%), 3 induced abortions (5.0%), and no stillbirths. Among livebirths, the mean gestational age was 37.4 ± 2.8 weeks and the mean birthweight was 2920.3 ± 650.0 g. All neonates had reassuring 5-minute Apgar scores, 18 (32.7%) were admitted to the Neonatal Intensive Care Unit/Special Care Nursery (NICU/SCN), and 8 (14.5%) were noted to have a mild congenital abnormality. Conclusion: This study shows promising perinatal outcomes for patients with PAC and their neonates. Ongoing surveillance of PAC is needed to better inform care for this patient population.