Review Tamoxifen and pregnancy L. Barthelmes, and C.A. Gateley Breast Unit, Department of Surgery, Royal Gwent Hospital, Newport NP 20 2 UB, Wales, UK Summary Women are conventionally advised to stop tamoxifen before attempting pregnancy. The risks of congenital malformations or late teratogenic manifestations in adulthood are unknown. Following an informed discussion about the uncertainties of tamoxifen exposure on pregnancy women should be offered the choice whether to continue or stop tamoxifen before attempting pregnancy. An unexpected pregnancy in a women taking tamoxifen could continue if the pregnant woman accepts the possibility of a teratogenic effect that tamoxifen could have on the fetus. doi:10.1016/j.breast.2004.08.007 The Breast Volume 13, Issue 6 , December 2004, Pages 446-451 Ann's NOTE: The definition of teratogenic is "Substances such as chemicals or radiation that cause abnormal development of a embryo". (source: hyperdictionary.com) From www.ilpi.com (MSDS HyperGlossary): "Pregnant women should avoid all contact with teratogens, particularly during the first three months of pregnancy, as this can result in damage to the developing child". An example of a teratogenic drug is DES diethylstilbestrol. "Cancer: All DES daughters (women whose mothers took DES while pregnant with them) have a risk of about 1 in 1,000 for a rare cancer of the vagina or cervix called clear cell adenocarcinoma". "Although less is known about the consequences of DES exposure in men than in women, a number of concerns have been identified. It is important for men who know or suspect they are DES sons to be aware of possible problems and know what to do about them. Most men exposed to DES before birth have no known increased risk of health problems. However, some DES sons do face an increased risk for problems with their genital organs. These range from harmless irregularities to problems which may require medical treatment. Many people, including some doctors, do not know that men can be affected by DES exposure before birth". "Women who took DES have a somewhat higher risk for breast cancer. They should pay particular attention to their breast care: practice monthly breast self-exam, have annual clinical breast exams and mammography". Third Generation: "Little research has been done on this subject, and DES Action urges research into this important topic. The National Cancer Institute is considering plans to study this subject further. Animal research conducted at the National Institute of Environmental Health Sciences has revealed a higher risk for reproductive tumors in third generation offspring of female DES-exposed mice. A study in the Netherlands revealed a higher rate of hypospadias (a male birth defect where the opening of the urethra is located on the side rather than the end of the penis) in boys born to DES daughters, i.e. third generation males". Source: http://www.desaction.org/ Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.