Breast Cancer Risk and Childbirth Timing
Author Information
Author(s): Albrektsen G, Heuch I, Hansen S, Kvåle G
Primary Institution: University of Bergen
Hypothesis
How does the timing of childbirth affect breast cancer risk?
Conclusion
The study found that the timing of childbirth significantly influences breast cancer risk, with older maternal age at first birth associated with increased long-term risk.
Supporting Evidence
- Women with two to five full-term births had a lower risk of breast cancer compared to nulliparous women.
- Older maternal age at first birth was linked to a higher long-term risk of breast cancer.
- A transient increase in breast cancer risk was observed shortly after childbirth, especially after a late first birth.
Takeaway
Having babies at a younger age can lower the risk of breast cancer, but if you have your first baby later in life, your risk might go up.
Methodology
The study analyzed data from the Norwegian Population Registry, focusing on reproductive history and breast cancer diagnoses among women aged 20-74.
Potential Biases
The data were based on compulsory registrations, minimizing selection or recall bias.
Limitations
Some misclassification of parity might have occurred, particularly for women born before 1935.
Participant Demographics
Norwegian women born between 1925 and 1979, aged 20-74 years during the study.
Statistical Information
Confidence Interval
0.85–0.96 for two births vs uniparous women
Statistical Significance
p<0.0001
Digital Object Identifier (DOI)
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