iPhone apps for obstetrics

Perinatal Calculators is suite of calculators that maternal care providers can use in the office or on L&D to help streamline clinical decision making and counseling.  It does not need an internet connection to run as it is not web based.   Algorithms are often used to counsel patients based on published data, but unlike other specialties it would appear that obstetrics has been a forgotten specialty in the eyes of app developers.  Obstetricians and perinatologists are  busy and time is precious so developing an app to avoid going online or looking up information that could easily be stored on our iPhones, iPads  and at our finger tips is essential.

The ultrasound risk assessment calculator allows you to enter a priori risk or use age related baseline risk and adjust for different ultrasound markers.  Likelihood ratios are shown for each marker.  This can be used without an internet connection and the screen is easy to use and navigate on all iOS devices.

The VBAC risk assessment calculators are unique in that there is one for office based counseling before labor begins and a second for counseling on admission to labor and delivery and incorporates cervical exam parameters.  These are based on published nomograms.

An insulin calculator for initiating treatment in gestational diabetics is also included as well with automatically built in logic for insulin multiplier by trimester. Gives dosages for both lantus/listed regimen or an NPH/regular insulin regimen.

CVR calculator for CPAM, MCA doppler MOM calculator, and Extreme Preterm Survival calculator are also included.

cfDNA PPV Calculator estimates positive predictive value (PPV) and negative predictive value (NPV) for prenatal cell-free DNA (cfDNA) screening using Bayesian probability.

Conditions supported:

• Trisomy 21

• Trisomy 18

• Trisomy 13

• Monosomy X (45,X)

• 47,XXY

• 47,XYY

• 47,XXX

For autosomal trisomies, pretest probability may be derived from maternal-age population risk tables (midtrimester risk by age at term). For sex chromosome aneuploidies, pretest probability can be entered as population prevalence (1 in N). Sensitivity and specificity are user-editable to reflect lab-specific performance.

This app is for screening support and educational use. It does not provide a diagnosis. Positive screening results should be confirmed with diagnostic testing and clinical correlation.

New calculators will be added periodically and updates are always free.


Please feel free to send us an e-mail with any questions or comments.