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Gynecology & Obstetrics

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Obstetric Ultrasound

Obstetric ultrasound at Johns Hopkins is AIUM-accredited and employs registered (RDMS) ultrasonographers or Diagnostic Medical Sonographer Candidates (DMS) who specialize in the field of obstetrics and high-risk obstetrics. We have state-of-the-art ultrasound machines, including those with 3D/4D capabilities.

We provide a wide range of ultrasound services:

  • First trimester scans
  • Comprehensive fetal anatomy screens
  • Fetal growth scans
  • Scans on multiple gestations
  • Second opinion/consultation for known/suspected fetal abnormalities.

In addition, we offer fetal echocardiography, first trimester Nuchal translucency screening, and ultrasound guidance for invasive fetal procedures.

Results you can trust

All scans are interpreted by one of our board-certified perinatologists. In most cases, study results are provided to the patient before her departure from our department.

Coordination of appointments with neonatal/pediatric specialists is provided for those patients requiring such services.

Specific Patient Instructions

  1. Please be sure to arrive at least 10-15 minutes prior to your scheduled appointment to allow time for registration.
  2. Please have your referral and a current insurance card with you at the time of your visit.
  3. For your convenience, we have provided a registration form which can be accessed on-line as well as additional relevant information. Please click on the "Contact Us" navigation bar on the left side of this page.

Frequently Asked Questions

Is ultrasound harmful to my baby?

Ultrasound is a specialized exam using sound waves (not x-rays) to visualize your baby. No radiation is involved. To learn more, please visit: American Institute of Ultrasound in Medicine. Select “Conclusions Regarding Epidemiology for Obstetrical Ultrasound" and/or "Prudent Use and Clinical Safety".

How long will the exam take?
We allow one hour per patient for each exam; however, some exams take less time than others. Multiple gestations (twins, triplets, and higher) are allotted the proper amount of time needed to perform a complete exam. Sometimes because of unexpected findings, a scan may take longer than expected; therefore, some scheduling delays may occur. Be assured that each patient is given the amount of time needed to perform a comprehensive ultrasound study.

Will I need a full bladder?

You will need a full bladder if:

  • You are fewer than 12 weeks pregnant.
  • You are having a CVS procedure.

Your bladder needs to be half full if:

  • You are between 12 to 24 weeks pregnant.

You do not need a full bladder if:

  • You are having amniocentesis.
  • You are more than 24 weeks pregnant.

Can I eat before my appointment?

It is fine to eat before your ultrasound, unless specifically instructed otherwise by a physician.

Can I get a digital recording of my baby?

Digital recording for nondiagnostic purposes is not performed; however, keepsake still images of your baby will be provided. Please be aware that fetal position may limit our ability to obtain optimal keepsake images.

Can I have a 3D ultrasound of my baby?

While we do have 3D/4D ultrasound machines, they are reserved for cases in which there is a known suspected fetal abnormality.

In the setting of a fetal abnormality, 3D/4D technology may sometimes be beneficial; however, the limitations of 3D are often the same as 2D; therefore, this technology is used at the attending physician's discretion. We do provide 2D keepsake images of your baby which are obtained at the time of your scan. Please be aware that fetal position may limit our ability to obtain optimal keepsake images.

The Food and Drug Administration (FDA) cautions against the use of 3D/4D imaging for entertainment purposes. Click here to read the official statement of the American Institute of Ultrasound in Medicine regarding the use of 3D/4D technology.

Will I be able to find out the sex of my baby?

Depending upon the baby's position and gestational age, we can tell you what sex we think the baby will be. Please keep in mind that ultrasound is not 100 percent accurate in fetal sex determination.