Successful pregnancy after breast cancer therapy: dream or reality?

Breastfeeding is Possible: A Systematic Review on the Feasibility and Challenges of Breastfeeding Among Breast Cancer Survivors of Reproductive Age

BACKGROUND

Breastfeeding is the biologically normative mode of feeding human infants, and reduces the risk of breast cancer for mothers. This systematic review assesses engagement in breastfeeding and the factors associated with breastfeeding among breast cancer survivors.

METHODS

An online literature search was performed using the PubMed, Embase, CINAHL, PsychInfo, and Web of Science databases. Inclusion criteria were original research articles written in English, published in peer-reviewed journals from 1 January 1990 to 25 November 2019, and included data on breast cancer survivors who attempted breastfeeding.

RESULTS

Thirteen studies were included in the systematic review. Between 7.7 and 90.9% of women attempted breastfeeding. Breastfeeding among participants varied from a few weeks to approximately 2 years. Common factors leading to breastfeeding were use of the contralateral breast, support from others, lactation counseling and advice from an International Board-Certified Lactation Consultant, being motivated to breastfeed, frequent feedings, and use of galactagogues. Common barriers were medical counseling against breastfeeding, insufficient milk production, lack of support, refusal of the infant to breastfeed from the treated breast, and being tired from relying on one breast.

CONCLUSIONS

Breastfeeding from the unaffected breast is feasible for some breast cancer survivors. Successful breastfeeding may require multilevel support and expert advice.

Prevalence of preterm, low birthweight, and small for gestational age delivery after breast cancer diagnosis: a population-based study

BACKGROUND

Black-white disparities in breast cancer incidence rates and birth outcomes raise concerns about potential disparities in the reproductive health of premenopausal breast cancer survivors. We examined the prevalence of preterm birth (PTB), low birthweight (LBW), and small for gestational age (SGA) by breast cancer history and effect modification by race.

METHODS

We analyzed linked North Carolina birth records and Central Cancer Registry files from 1990 to 2009 (n = 2,325,229). We used multivariable negative log-binomial regression to calculate prevalence ratios (PRs) and 95% confidence intervals (CIs) for the association between breast cancer history and PTB, LBW, and SGA.

RESULTS

Of 1,912,269 eligible births, 512 births were to mothers with a previous breast cancer diagnosis history. Average age at breast cancer diagnosis was 31.8 years (SD = 4.7). Mean time from diagnosis to delivery was 3.3 years (SD = 2.8). After multivariable adjustment, the PR was 1.67 (95% CI, 1.42-1.97) for PTB, 1.50 (95% CI, 1.23-1.84) for LBW, and 1.30 (95% CI, 1.05-1.61) for SGA comparing women with a breast cancer history to the general population. Among black mothers, the PRs associated with breast cancer history for PTB, LBW, and SGA were 1.31 (95% CI, 1.00-1.72), 1.49 (95% CI, 1.14-1.94), and 1.44 (95% CI, 1.11-1.87), respectively. The corresponding PRs among white mothers were 2.06 (95% CI, 1.67-2.54), 1.53 (95% CI, 1.12-2.08), and 1.10 (95% CI, 0.77-1.58), respectively. The interaction between breast cancer history and race was statistically significant for associations with PTB, but not for LBW or SGA.

CONCLUSIONS

In our data, women with a breast cancer history were at higher risk of delivering a PTB, LBW, or SGA infant, especially if they received chemotherapy or gave birth within 2 years of their breast cancer diagnosis date.

Reproduction after breast cancer

Breast cancer is the most frequently occurring cancer in women of developed countries, and as a result of new developments in breast cancer treatment, more women are cured after being diagnosed with this disease. It is important that fertility preservation strategies are addressed before chemotherapy, because chemotherapy may induce premature ovarian failure (depending on the woman's age, the drugs used, the dosage and duration of treatment). Among possible solutions are embryos or oocytes cryopreservation, ovarian tissue cryopreservation-freezing with a subsequent orthotopic and heterotopic autotransplantation, whole ovary cryopreservation, ovarian suppression with gonadotropin-releasing hormone (GnRH) analogues, which inhibit ovarian follicular depletion induced by chemotherapeutic agents and in vitro fertilisation (IVF) after ovulation induction with aromatase inhibitors or tamoxifen.