Breast Cancer and Pregnancy
 Basics
Description
Breast cancer in pregnancy is defined as breast cancer that is diagnosed during pregnancy, during lactation, and up to 12 months postpartum.
Epidemiology
Incidence
- Gestational breast cancer is one of the most common pregnancy-associated malignancies as well as cervical cancer.
 - Breast cancer in pregnancy has an incidence of approximately 0.3/1,000 deliveries (1).
 
Etiology and Pathophysiology
Genetics
- BRCA1 and BRCA2 mutation carriers have greatly increased risk of breast cancer overall and may be more likely to develop breast cancer during pregnancy.
 - Multiparity appears protective in BRCA1 carriers but is associated with increased risk in BRCA2 carriers.
 - Other significant mutations include p53 (Li-Fraumeni syndrome) and PTEN (Cowden syndrome).
 
Risk Factors
- Age
- Increased risk with advanced age
 - First pregnancy after age 35 years increases risk.
 
 - Early menarche and late menopause
 - Family history
- Breast cancer in first-degree relatives
 - First-degree relatives with premenopausal breast cancer further increase risk.
 
 - Nulliparity
 - Exposure to radiation
 - Social
- Increased consumption of alcohol
 - Obesity
 - Sedentary lifestyle (2)
 
 
General Prevention
- Reduce the risk of breast cancer by maintaining a healthy weight.
 - The benefits with moderate exercise such as brisk walking are seen at all age groups including postmenopausal women.
 
Commonly Associated Conditions
- Women with gestational diabetes mellitus (GDM) are at 1.5 times greater risk of breast cancer as compared with women who do not have GDM.
 - Lower risk of breast cancer is observed in women who have pregnancy-related hypertensive disorders such as preeclampsia.
 
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Citation
Domino, Frank J., et al., editors. "Breast Cancer and Pregnancy." 5-Minute Clinical Consult, 34th ed., Wolters Kluwer, 2026. Medicine Central, im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/816935/2.1/Breast_Cancer_and_Pregnancy. 
Breast Cancer and Pregnancy. In: Domino FJF, Baldor RAR, Golding JJ, et al, eds. 5-Minute Clinical Consult. Wolters Kluwer; 2026. https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/816935/2.1/Breast_Cancer_and_Pregnancy. Accessed November 3, 2025.
Breast Cancer and Pregnancy. (2026). In Domino, F. J., Baldor, R. A., Golding, J., & Stephens, M. B. (Eds.), 5-Minute Clinical Consult (34th ed.). Wolters Kluwer. https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/816935/2.1/Breast_Cancer_and_Pregnancy
Breast Cancer and Pregnancy [Internet]. In: Domino FJF, Baldor RAR, Golding JJ, Stephens MBM, editors. 5-Minute Clinical Consult. Wolters Kluwer; 2026. [cited 2025 November 03]. Available from: https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/816935/2.1/Breast_Cancer_and_Pregnancy.
* Article titles in AMA citation format should be in sentence-case
TY  -  ELEC
T1  -  Breast Cancer and Pregnancy
ID  -  816935
ED  -  Domino,Frank J,
ED  -  Baldor,Robert A,
ED  -  Golding,Jeremy,
ED  -  Stephens,Mark B,
BT  -  5-Minute Clinical Consult, Updating
UR  -  https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/816935/2.1/Breast_Cancer_and_Pregnancy
PB  -  Wolters Kluwer
ET  -  34
DB  -  Medicine Central
DP  -  Unbound Medicine
ER  -  

5-Minute Clinical Consult

