If prior history of cesarean delivery or uterine instrumentation is present, assessment for placenta accreta spectrum can be performed. US Pregnant Uterus Transvaginal Transvaginal examination of the pregnant uterus and cervix can be performed as an adjunct for limited transabdominal fetal evaluation. Additional indications include assessment of the cervix and placenta and detection of vasa previa. Typically, transvaginal imaging is performed only if transabdominal evaluation is considered suboptimal or incomplete. If prior history of cesarean delivery or uterine instrumentation is present, assessment for placenta accreta spectrum can be performed. Variant 6: Multiple gestations. Monochorionic twins. Growth and antepartum surveillance. In this variant, the patient is known to be pregnant with uncomplicated MC multiple gestation. The fetuses have been demonstrated to share a single placenta. Given the higher incidence of growth disturbance, congenital abnormalities, and complications unique to MC twinning, assessment of growth and surveillance for fetal well- being is indicated. In addition to monitoring fetal size and interval growth, ongoing evaluation includes amniotic fluid assessment and the search for possible development of TTTS, TAPS, or sFGR. Typically, surveillance begins at 16 weeks for MC twins, with fetal biometry performed every 2 to 3 weeks [9,12]. Assessment for potential TTTS or other complications of MC twinning is performed every 2 weeks [9,12]. If there is discordance in fetal size or amniotic fluid volume, shorter interval surveillance may be warranted [13]. MRI Fetal Without and With IV Contrast MRI fetal without and with IV contrast does not have a role in growth and antepartum surveillance of MC gestations. Gadolinium contrast is usually not administered for fetal indications. MRI Fetal Without IV Contrast MRI fetal without IV contrast can be useful for antepartum surveillance for a known abnormality.
Multiple Gestations. If prior history of cesarean delivery or uterine instrumentation is present, assessment for placenta accreta spectrum can be performed. US Pregnant Uterus Transvaginal Transvaginal examination of the pregnant uterus and cervix can be performed as an adjunct for limited transabdominal fetal evaluation. Additional indications include assessment of the cervix and placenta and detection of vasa previa. Typically, transvaginal imaging is performed only if transabdominal evaluation is considered suboptimal or incomplete. If prior history of cesarean delivery or uterine instrumentation is present, assessment for placenta accreta spectrum can be performed. Variant 6: Multiple gestations. Monochorionic twins. Growth and antepartum surveillance. In this variant, the patient is known to be pregnant with uncomplicated MC multiple gestation. The fetuses have been demonstrated to share a single placenta. Given the higher incidence of growth disturbance, congenital abnormalities, and complications unique to MC twinning, assessment of growth and surveillance for fetal well- being is indicated. In addition to monitoring fetal size and interval growth, ongoing evaluation includes amniotic fluid assessment and the search for possible development of TTTS, TAPS, or sFGR. Typically, surveillance begins at 16 weeks for MC twins, with fetal biometry performed every 2 to 3 weeks [9,12]. Assessment for potential TTTS or other complications of MC twinning is performed every 2 weeks [9,12]. If there is discordance in fetal size or amniotic fluid volume, shorter interval surveillance may be warranted [13]. MRI Fetal Without and With IV Contrast MRI fetal without and with IV contrast does not have a role in growth and antepartum surveillance of MC gestations. Gadolinium contrast is usually not administered for fetal indications. MRI Fetal Without IV Contrast MRI fetal without IV contrast can be useful for antepartum surveillance for a known abnormality.