Obstetrum: OB-GYN Calculator

Clinical obstetric calculators for healthcare professionals — updated 2026. Gestational dating (ACOG CO 700), estimated fetal weight, fundal height, gestational weight gain, fetal Doppler, Bishop score and VBAC prediction. 100% local data.

Most obstetric calculator apps on the market stopped being updated between 2014 and 2021. Obstetrum keeps its tools aligned with current international guidelines (ACOG, WHO, FIGO, NICE, INTERGROWTH-21st).

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

LABOR AND DELIVERY
• Bishop score — Score 0–13 and cervical favorability
• Labor progress — Stage diagnosis and management support
• 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
• Unlimited records, PDF reports, record comparison, ad-free

Not a regulated medical device. Clinical decision support tool for healthcare professionals. Always verify results against your institutional protocols and clinical judgment.
Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/