A small study has shown that the anticipated changes in breast density are less pronounced during pregnancy than during lactation, and that most pregnant patients had scattered or heterogeneously dense fibroglandular tissue [44]. Many studies have shown that mammograms may be diagnostic in 74% to 100% of pregnant women [7,24-28]. With current digital techniques and increased use of DBT, the ability to detect breast cancer with mammography in pregnant patients may improve. There are several studies that report screen-detected PABC in a small number of patients [7,24]. US Breast Throughout pregnancy, there is progressive ductal and lobular hyperplasia as well as increased duct ectasia. These changes lead to prominent hypoechoic ducts and lobules with diffuse decreased breast echogenicity [9,10]. There are no studies available at this time evaluating the use of screening whole-breast US during pregnancy. Despite physiologic changes that alter the sonographic appearance of the breasts during pregnancy, screening whole- breast US may be used as a supplemental screening modality in pregnant women 40 and older, especially those at elevated risk. It is, however, important to keep in mind that screening US may increase the false-positive rate and prompt additional biopsies. MRI Breast It is well established that IV gadolinium chelates cross the placenta and enter the fetal circulation. Although there are no reported adverse fetal effects due to IV gadolinium in the pregnant mother, there is the potential for the dissociation of free toxic gadolinium ion with limited data in this patient population. Guidelines regarding gadolinium administration during pregnancy are outlined in detail in the ACR Manual on Contrast Media [33]. Because of the concerns regarding gadolinium crossing the placenta and limited data regarding its safety in this setting, screening breast DCE-MRI is not recommended in pregnant women with any breast cancer risk profile.
Breast Imaging of Pregnant and Lactating Women. A small study has shown that the anticipated changes in breast density are less pronounced during pregnancy than during lactation, and that most pregnant patients had scattered or heterogeneously dense fibroglandular tissue [44]. Many studies have shown that mammograms may be diagnostic in 74% to 100% of pregnant women [7,24-28]. With current digital techniques and increased use of DBT, the ability to detect breast cancer with mammography in pregnant patients may improve. There are several studies that report screen-detected PABC in a small number of patients [7,24]. US Breast Throughout pregnancy, there is progressive ductal and lobular hyperplasia as well as increased duct ectasia. These changes lead to prominent hypoechoic ducts and lobules with diffuse decreased breast echogenicity [9,10]. There are no studies available at this time evaluating the use of screening whole-breast US during pregnancy. Despite physiologic changes that alter the sonographic appearance of the breasts during pregnancy, screening whole- breast US may be used as a supplemental screening modality in pregnant women 40 and older, especially those at elevated risk. It is, however, important to keep in mind that screening US may increase the false-positive rate and prompt additional biopsies. MRI Breast It is well established that IV gadolinium chelates cross the placenta and enter the fetal circulation. Although there are no reported adverse fetal effects due to IV gadolinium in the pregnant mother, there is the potential for the dissociation of free toxic gadolinium ion with limited data in this patient population. Guidelines regarding gadolinium administration during pregnancy are outlined in detail in the ACR Manual on Contrast Media [33]. Because of the concerns regarding gadolinium crossing the placenta and limited data regarding its safety in this setting, screening breast DCE-MRI is not recommended in pregnant women with any breast cancer risk profile.