# Obstetrum: OB-GYN Calculator — Gestational Age & Fetal Weight

> Gestational Age & Fetal Weight (iPhone/iPad app by Leonel Pimentel.)

- Source: https://appshunter.io/ios/app/obstetrum-ob-gyn-calculator/id6761284412 (this page in markdown: same URL + `.md`)
- Developer: [Leonel Pimentel](https://appshunter.io/developer/1847101134)
- Category: Medical, Health & Fitness
- Price: Free with in-app purchases
- Age rating: 17+
- Requires: iOS 15.0 · 48 MB
- Languages: American English, French (France), Brazilian Portuguese, Latin American Spanish
- Released: 2026-04-09
- Data updated: 2026-07-08
- User reviews in markdown: https://appshunter.io/ios/app/obstetrum-ob-gyn-calculator/id6761284412/reviews.md

## What is Obstetrum?

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/

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| Obstetrum Premium | $2.99 | per month |
| Obstetrum Premium | $24.99 | per year |



## Version history (last 3 releases)

### 1.2 — 2026-04-10

- Improved IV oxytocin calculator
- Some minor bugs fixed
- Translated strings

### 1.1 — 2026-04-09

- Improved IV oxytocin calculator
- Some minor bugs fixed
- Translated strings

### 1.0 — 2026-04-09

No release notes.

## More apps by Leonel Pimentel

- [Goterum: IV Drip Calculator](https://appshunter.io/ios/app/goterum-iv-drip-calculator/id6754208545)

All apps by Leonel Pimentel: https://appshunter.io/developer/1847101134

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-07-08.*