Breast cancer risk: protective effect of an early first full-term pregnancy versus increased risk of induced abortion

Oncol Nurs Forum. 1997 Jul;24(6):1025-31.


Purpose/objectives: To examine the question of whether an early first full-term pregnancy (FFTP) protects against breast cancer and whether interruption of the pregnancy with an induced abortion increases breast cancer risk.

Data sources: Published medical and epidemiology journal articles, books, scientific reports, news interviews of researchers, scientific journals.

Data synthesis: Continually increasing breast cancer rates cannot be explained by the American Cancer Society risk factors, which account for only 25% of cases. Induced abortion is a newly recognized risk factor and has been prevalent in our society since it was legalized in 1973.

Conclusions: Early FFTP confers protection, while induced abortion confers risk. Most specific and controlled variables studies indicate 150% risk for abortions performed on women younger than 18 years of age. Studies have yet to discover the full impact of induced abortion because women who underwent legalized abortion in 1973 are just reaching ages of highest breast cancer incidence. IMPLICATIONS FOR NURSES: Awareness of a controversial risk factor and its relevance to women allows nurses to include this information when educating and supporting patients. Specifically, nurses need to include questions on this reproductive risk when eliciting a patient's reproductive history. Nurses should further be aware of the emotional impact disclosure may have.

Publication types

  • Review

MeSH terms

  • Abortion, Induced / adverse effects*
  • Adolescent
  • Adult
  • Age Factors
  • Breast Neoplasms / epidemiology
  • Breast Neoplasms / prevention & control*
  • Female
  • Humans
  • Pregnancy / physiology*
  • Reproductive History*
  • Risk Factors