Anderson RA, et al. - In females aged ≤ 39 years, researchers sought to assess the impact of cancer on subsequent chance of pregnancy. Fewer pregnancies were achieved among cancer survivors across all cancer types. These individuals also showed lower chances of achieving the first pregnancy.

Methods

• In this retrospective cohort study, first incident cancer diagnosed between 1981 and 2012 was correlated to subsequent pregnancy in all female patients in Scotland aged 39 years or less at cancer diagnosis (n=23,201).
• Researchers included pregnancies up to end of 2014.
• They compared females from the exposed group who were not pregnant before cancer diagnosis (n = 10,271) with general population controls matched for age, deprivation quintile and year of diagnosis.
• To calculate standardized incidence ratios (SIR) for pregnancy (standardized for age and year of diagnosis) they linked Scottish Cancer Registry records to hospital discharge records.
• They also linked to death records.
• Further, they selected women from the exposed group who had not been pregnant prior to their cancer diagnosis who were compared with a matched control group from the general population.
• For breast cancer, Hodgkin lymphoma, leukemia, cervical cancer and brain/CNS cancers, they performed additional analyses.

Results

• Fewer pregnancies among cancer survivors were achieved: SIR 0.62 (95% CI: 0.60, 0.63).
• Lower chance of achieving a first pregnancy was also noted (adjusted hazard ratio = 0.57; 95% CI: 0.53, 0.61) for women > 5 years after diagnosis, with marked reductions in women with breast, cervical and brain/CNS tumors, and leukemia.
• They noted a reduced effect with more recent treatment period overall and in cervical cancer, breast cancer and Hodgkin lymphoma, but it remained unchanged for leukemia or brain/CNS cancers.
• After a cancer diagnosis, lower proportion of pregnancies ended in termination, and higher proportion ended in live birth (78.7 vs 75.6%, CI of difference: 1.1, 5.0).