Obstetrum: OB-GYN Calculator
Gestational Age & Fetal Weight
Free · In‑App Purchases · Designed for iPad. Not verified for macOS.
Updated 2026. Obstetric insulin with 7 guidelines (ADA/ACOG, NICE, FIGO, ALAD, ADIPS, CDA, GEDE). PPH WHO 2025 Bundle MOTIVE. VBAC 3 models. 100% local data.
11 active obstetric calculators — updated 2026. Insulin dosing with 7 international guidelines (ADA/ACOG, NICE, FIGO, ALAD, ADIPS, CDA, GEDE). PPH with WHO 2025 protocol. VBAC with 3 predictive models. ACOG CO 700 gestational dating. 100% local data.
Most obstetric calculator apps on the market stopped being updated between 2014 and 2021. Obstetrum maintains current clinical guidelines — including the WHO 2025 PPH protocol and FDA 2026 CDS traceability in the insulin module.
PRENATAL CARE
• Gestational age — ACOG CO 700 dating hierarchy (IVF > 1st trim CRL USG > LMP > 2nd/3rd trim USG)
• Estimated fetal weight — Hadlock 1991, INTERGROWTH-21st percentiles (p3–p97)
• Fundal height — INTERGROWTH-21st, weeks 13–40, serial trend curve
• Gestational weight gain — IOM guidelines by pre-pregnancy BMI
• Fetal Doppler — Umbilical fluxometry, resistance indices, FGR staging
• Insulin in pregnancy — 7 guidelines: ADA/ACOG, NICE, FIGO, ALAD, ADIPS, CDA, GEDE. GDM and pregestational T1/T2 diabetes. No other app offers multi-guideline obstetric insulin dosing.
OBSTETRIC EMERGENCIES
• Oxytocin — Induction and augmentation protocols
• Magnesium sulfate — Zuspan protocol, loading and maintenance
• Bishop score — Score 0–13, favorability and ripening recommendation
• Postpartum hemorrhage — WHO 2025 Bundle MOTIVE, shock index, evidence levels A/B/C
PERINATAL PERIOD
• VBAC predictor — Grobman 2007, updated Grobman 2021, and Flamm-Geiger
CLINICAL RECORDS & PDF
Patient calculation history, professional PDF reports with plotted percentiles, record comparison, physician signature.
PRIVACY
Local SQLite database. No remote servers. No cloud sync. No mandatory accounts.
PREMIUM — all calculators are accessible without subscription
• Unlimited records, PDF reports, record comparison, ad-free
Not a regulated medical device. Clinical decision support tool for healthcare professionals.
Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
- Improved IV oxytocin calculator
- Some minor bugs fixed
- Translated strings
The developer, Leonel Pimentel, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Used to Track You
The following data may be used to track you across apps and websites owned by other companies:
- Identifiers
- Usage Data
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Identifiers
- Usage Data
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Leonel Pimentel
- Size
- 50 MB
- Category
- Medical
- Compatibility
Requires iOS 15.0 or later.
- iPhone
Requires iOS 15.0 or later. - iPad
Requires iPadOS 15.0 or later. - iPod touch
Requires iOS 15.0 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
English and 3 more
- English, French, Portuguese, Spanish
- Age Rating
16+
- 16+
- Frequent
Medical Treatment information
Contains
Advertising
- In-App Purchases
Yes
- Obstetrum Premium $24.99
- Obstetrum Premium $2.99
- Copyright
- © BlastoApps
