Tamoxifen and pregnancy.
1Breast Unit, Department of Surgery, Royal Gwent Hospital, Newport NP20 2UB, Wales, UK. barthelmes@tinyonline.co.uk
Breast (Edinburgh, Scotland)
|November 27, 2004
Summary
Women considering pregnancy can choose to continue or stop tamoxifen. The risks of tamoxifen exposure during pregnancy, including birth defects, are not fully understood, requiring informed patient choice.
Area of Science:
- Reproductive medicine
- Pharmacology
- Obstetrics
Background:
- Tamoxifen is a common breast cancer treatment.
- Conventional advice recommends discontinuing tamoxifen before conception.
- Potential risks of fetal exposure to tamoxifen are not well-established.
Purpose of the Study:
- To evaluate the implications of continuing tamoxifen during pregnancy.
- To inform clinical practice regarding tamoxifen use in women of childbearing potential.
- To support shared decision-making between patients and clinicians.
Main Methods:
- Review of existing literature on tamoxifen teratogenicity.
- Analysis of potential risks and benefits of tamoxifen exposure in utero.
- Discussion of ethical considerations in managing pregnancy while on tamoxifen.
Main Results:
- The precise risks of congenital malformations from tamoxifen are unknown.
- Late teratogenic effects in adulthood following in-utero exposure are not documented.
- Informed consent is crucial for managing unexpected pregnancies in women on tamoxifen.
Conclusions:
- Women should be offered a choice to continue or stop tamoxifen before pregnancy planning.
- Informed discussion about uncertainties is paramount.
- Continuation of tamoxifen in pregnancy may be an option if risks are accepted by the patient.
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