Interrupting Endocrine Therapy to Attempt Pregnancy after Breast Cancer

On May 4, 2023 our practice-changing POSITIVE study has been published in the prestigious New England Journal of Medicine

For young women with hormone-sensitive early breast cancer desiring pregnancy, pausing endocrine therapy to try to become pregnant can be done without a short-term risk of breast cancer recurrence.

The study, which followed up participants for a median of 41 months, found that 8.9% of women who temporarily stopped endocrine therapy experienced a breast cancer recurrence, compared to 9.2% of women in an external control group who did not stop.

The study also found that most women were able to have healthy babies. Of the 497 women who provided information, 74% had at least one pregnancy, and most pregnancy occurred within two years. Of the women who became pregnant at least once, 86% had a live birth, and 365 babies were born during the study. 

These results represent an important breakthrough in the treatment of young women with hormone-sensitive breast cancer and provide encouraging guidance for the treatment of women with breast cancer who wish to have a baby.

However, as hormone receptor-positive breast cancer can recur many years after the initial diagnosis, longer follow-up is needed to provide definitive reassurance that endocrine therapy can be safely interrupted for pregnancy in the long term. It is therefore our commitment to follow up the study participants and to assess recurrence risk over time until 2029.

We are currently seeking forward-looking donors who are interested in supporting the continuation of the practice-changing POSITIVE study whose final results could definitively break the resistance that hinders this important life plan for many young patients. DONATE

Article: Interrupting Endocrine Therapy to Attempt Pregnancy after Breast Cancer  
Editorial: POSITIVE Results for Breast Cancer Survivors Who Desire Pregnancy  


"With these initial and reassuring results you have given hope to many young patients.
From the bottom of our hearts, THANK YOU!"


Ilaria, a POSITIVE participant

  Claire and baby 1



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