This document addresses the use of maternity ultrasound in the outpatient setting. This document does not address nuchal translucency.

Note: Please see the following related document for additional information:

• RAD.00038 Use of 3-D, 4-D or 5-D Ultrasound in Maternity Care

Clinical Indications

Medically Necessary:

Maternity ultrasound is considered medically necessary for any of the following:

• Routine anatomy screen and dating:
  • One ultrasound of a pregnant uterus per member, per routine course of care;
  • Estimate gestational age for individuals with uncertain clinical dates.
• Known or suspected abnormality of maternal reproductive structure:
  • Clinical suspicion of cervical insufficiency (for example, abnormal cervix on physical examination, maternal history of second trimester pregnancy loss, prior cervical surgery, and diethylstilbestrol [DES] exposure);
  • To assess cervical length in the second or third trimester in individuals with a history of one or more pregnancy losses in the second or early third trimester or in individuals who have had preterm labor in the current pregnancy or in multi-fetal pregnancies;
  • Provide guidance for cervical cerclage placement;
  • Confirm suspected anatomical uterine abnormality, including fibroid uterus;
  • Localization of intrauterine device (IUD);
  • Evaluate a pelvic mass that has been detected clinically.
• Known or suspected abnormality of fetus:
  • Assess significant discrepancy between uterine size and dates;
  • Follow-up for observation of identified fetal or cord anomaly;
  • Evaluate suspected fetal growth abnormality (either growth restriction or macrosomia), and to follow proven or suspected intrauterine growth restriction;
  • Confirm suspected or follow confirmed diagnosis of polyhydramnios or oligohydramnios;
  • Estimate fetal weight or presentation in premature rupture of membranes or preterm labor;
  • Confirm suspected multiple gestation;
  • Serial evaluation of fetal growth in multi-fetal pregnancy. The most relevant clinical information is obtained when serial exams are done at least three weeks apart, beginning no earlier than 18 weeks gestation. In the case of monochorionic twins, one scan per two weeks in the third trimester is considered medically necessary;
  • For twin-twin transfusion syndrome, one scan per week and serial exams, more than once per week, beginning once the diagnosis of monochorionic twins or twin-twin transfusion is made;
  • Confirm suspected abnormal fetal position or presentation;
  • As an adjunct to external version from breech to vertex presentation;
  • A known or suspected exposure to Zika virus.
• Known or suspected abnormality of placenta:
  • Assess placental location associated with vaginal bleeding;
  • Suspected abruptio placenta;
  • Follow-up of subchorionic hematoma;
  • Suspected abnormal placental attachment (placenta accreta);
  • Suspected retained placenta or products of conception.
• Fetal viability or well-being:
  • Evaluate for threatened, incomplete, or missed abortion;
  • Evaluation of decreased fetal movement;
  • Non-reassuring fetal heart rate monitoring;
  • Suspected fetal death;
  • Assess amniotic fluid volume in post-term gestation.
• Other high risk conditions:
  • Assess vaginal bleeding of undetermined etiology;
  • Assess abdominal or pelvic pain of undetermined etiology;
  • Evaluation of fetal condition in late registrants for prenatal care;
  • History of unexplained fetal demise in a previous pregnancy;
  • Assess the fetus in cases with maternal risk factors such as family history of congenital abnormalities, chronic systemic disease (including but not limited to, hypertension, diabetes or sickle cell disease), preeclampsia, substance abuse or hyperemesis gravidarum;
  • Assessment of fetus after abnormal serum Alpha Fetal Protein (AFP), serum screen or multiple analyte serum screen, or cell-free fetal deoxyribonucleic acid (DNA) screening for aneuploidy;
  • Suspected ectopic pregnancy or hydatidiform mole, and to follow hydatidiform mole;
  • Assess the fetus in cases of Rhesus (Rh) isoimmunization and other causes of fetal hydrops;
  • Provide guidance for other testing, such as amniocentesis, chorionic villus sampling, and cordocentesis or procedures such as intrauterine blood transfusions or other in-utero fetal therapeutic procedures.

Not Medically Necessary:

Maternity ultrasound is considered not medically necessary for:

• Assessment of fetal well being, in the absence of the signs, symptoms, or conditions listed above;
• Only sex determination of the fetus;
• Providing a keepsake picture of the baby for the parents.