Early-life cancer, infertility, and risk of adverse pregnancy outcomes: a registry linkage study in Massachusetts

Purpose Investigate the relationship between history of cancer and adverse pregnancy outcomes according to subfertility/fertility treatment. Methods Deliveries (2004-2013) from Massachusetts (MA) Registry of Vital Records and Statistics were linked to MA assisted reproductive technology data, hospital discharge records, and Cancer Registry. The relative risks (RR) and 95% confidence intervals of adverse outcomes (gestational diabetes (GDM), gestational hypertension (GHTN), cesarean section (CS), low birth weight (LBW), small for gestational age (SGA), preterm birth (PTB), neonatal mortality, and prolonged neonatal hospital stay) were modeled with log-link and Poisson distribution generalized estimating equations. Differences by history of subfertility/fertility treatment were investigated with likelihood ratio tests. Results Among 662,630 deliveries, 2,983 had a history of cancer. Women with cancer history were not at greater risk of GDM, GHTN, or CS. However, infants born to women with prior cancer had higher risk of LBW (RR: 1.19 [1.07-1.32]), prolonged neonatal hospital stay (RR: 1.16 [1.01-1.34]), and PTB (RR: 1.19 [1.07-1.32]). We found clinically and statistically significant differences in the relationship between cancer history and SGA by subfertility/fertility treatment (p value, test for heterogeneity = 0.02); among deliveries with subfertility or fertility treatment, those with a history of cancer experienced a greater risk of SGA (RRsubfertile: 1.36 [1.02-1.83]). Conclusions Women with a history of cancer had greater risk of some adverse pregnancy outcomes; this relationship varied by subfertility and fertility treatment.