Pregnancy After Breast Cancer: A Systematic Review and Meta-Analysis

Abstract

PURPOSE Many patients and physicians remain concerned about the potential detrimental effects of pregnancy after breast cancer (BC) in terms of reproductive outcomes and maternal safety. This systematic review and meta-analysis aimed at providing updated evidence on these topics. METHODS A systematic literature review was conducted to identify studies including patients with a pregnancy after BC (PROSPERO number CRD42020158324). Likelihood of pregnancy after BC, their reproductive outcomes, and maternal safety were assessed. Pooled relative risks, odds ratios (ORs), and hazard ratios (HRs) with 95% CIs were calculated using random effects models. RESULTS Of 6,462 identified records, 39 were included involving 8,093,401 women from the general population and 112,840 patients with BC of whom 7,505 had a pregnancy after diagnosis. BC survivors were significantly less likely to have a subsequent pregnancy compared with the general population (relative risk, 0.40; 95% CI, 0.32 to 0.49). Risks of caesarean section (OR, 1.14; 95% CI, 1.04 to 1.25), low birth weight (OR, 1.50; 95% CI, 1.31 to 1.73), preterm birth (OR, 1.45; 95% CI, 1.11 to 1.88), and small for gestational age (OR, 1.16; 95% CI, 1.01 to 1.33) were significantly higher in BC survivors, particularly in those with previous chemotherapy exposure, compared with the general population. No significantly increased risk of congenital abnormalities or other reproductive complications were observed. Compared to patients with BC without subsequent pregnancy, those with a pregnancy had better disease-free survival (HR, 0.66; 95% CI, 0.49 to 0.89) and overall survival (HR, 0.56; 95% CI, 0.45 to 0.68). Similar results were observed after correcting for potential confounders and irrespective of patient, tumor, and treatment characteristics, pregnancy outcome, and timing of pregnancy. CONCLUSION These results provide reassuring evidence on the safety of conceiving in BC survivors. Patients' pregnancy desire should be considered a crucial component of their survivorship care plan.

Family size and duration of fertility in female cancer survivors: a population-based analysis

“…Women with breast cancer showed the greatest loss of family size when diagnosed at a younger age. Overall, only 8.6% of breast cancer survivors achieved a live birth after diagnosis, similar to the findings in a recent meta-analysis ( 39 ). For these younger women with breast cancer, these data illustrate the impact of the conflicts involved, including between family desires, ongoing endocrine treatment, and concerns over relapse.…”

Reproductive issues in carriers of germline pathogenic variants in the BRCA1/2 genes: an expert meeting

“…To further complicate the issue of pregnancy and breastfeeding in BRCA pathogenic variant carriers, we should consider the available data on the effect of subsequent pregnancy in the population of BRCA carriers already affected by BC. In this group of patients, current data show that subsequent pregnancy does not increase breast cancer-related events [17,18]. A large international study has recently shown that, independently of the receptor status and especially for BRCA1 pathogenic variants carriers, pregnancy after BC seems to be safe without negative consequences on maternal prognosis or fetal outcomes [19].…”

Knowledge, Practice, and Attitudes of Physicians in Low- and Middle-Income Countries on Fertility and Pregnancy-Related Issues in Young Women With Breast Cancer

“…These percentages were 69.6% and 63.0% in the BCY survey, suggesting more concerns in this regard among physicians practicing in LMICs. 20 These concerns are not supported by the growing amount of evidence that has become available showing that, after adequate treatment and period of follow-up, conceiving is safe for breast cancer survivors, 50,51 including among those with hormone receptor-positive disease. 52 Approximately 32% of responding physicians agreed that a temporary interruption of endocrine therapy to allow pregnancy in patients with hormone receptor-positive disease could be considered safe.…”

“… 49 However, breast cancer survivors have a lower likelihood of future conception compared with the general population and patients diagnosed with other cancers. 50 In addition to the impact of breast cancer treatment on ovarian function, physicians' concerns on the safety of pregnancy after breast cancer should be considered important reasons for these findings. 20 This is confirmed in our survey in which only half of the responding physicians disagreed with the statement that pregnancy in these patients may increase the risk of recurrence, a percentage that lowered to 41% in the case of women with hormone receptor–positive breast cancer.…”