OB Datum: Pregnancy Dating
EDD, IVF & Gestational Age
$1.99 · In‑App Purchases · Designed for iPad. Not verified for macOS.
Also Included In
Calculate from LMP, known GA, IVF/ART, conception, or an established EDD. No subscription or advertising.
Calculate and compare pregnancy dates with a clear explanation of every result.
OB Datum is a clinician-first pregnancy-dating workspace for iPhone and iPad. It performs deterministic calendar arithmetic and shows the source, formula, equivalent dates, and calculation-engine version for review.
CALCULATE FROM
• First day of the last menstrual period, with optional regular-cycle adjustment
• Documented conception or ovulation date
• An established estimated due date
• Gestational age documented on a known date
• IVF embryo-transfer date and documented embryo age
EVERY FEATURE INCLUDED
Every dating method, read-only Health import, full dating reconciliation, unlimited anonymous saved cases, formatted sharing, Calendar export, and custom timeline milestones are included in the downloaded app. There is no subscription, advertising, or separate feature purchase.
In Reconcile, keep an established EDD locked while comparing the dates implied by LMP, ultrasound gestational age, and IVF/ART. OB Datum reports signed calendar-day differences and never changes, averages, or recommends changing the established EDD.
EXPLORE THE TIMELINE
Calculate gestational age on a selected date, find the date corresponding to a gestational age, review descriptive milestones, and explore an interactive pregnancy wheel with accessible day and exact-date controls.
PRIVATE BY DESIGN
• No advertising or tracking
• No patient names, record numbers, contact details, or notes
• Anonymous saved calculations stay protected on your device
• Optional read-only import of the latest menstrual-cycle start from Health
• Calendar export includes only the EDD and no patient identifiers
• The widget opens OB Datum without displaying pregnancy or case data
OB Datum also provides a privacy-safe due-date action for Shortcuts and shareable calculation summaries.
OB Datum supports date arithmetic and clinical review. It does not diagnose, prescribe, select a delivery date, or replace professional judgment. Independently verify every input, result, and source before clinical use.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Every OB Datum feature is now included in the downloaded app. Use known gestational age, IVF/ART dating, Health import, Reconcile, unlimited anonymous cases, sharing, Calendar export, and custom milestones without a separate in-app purchase. Clinical sources now appear as non-interactive bibliography. Calculations remain private, offline, and independently reviewable.
The developer, VLR Software, 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 Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- VLR Software LLC
- Size
- 8.9 MB
- Category
- Medical
- Compatibility
Requires iOS 26.0 or later.
- iPhone
Requires iOS 26.0 or later. - iPad
Requires iPadOS 26.0 or later. - Mac
Requires macOS 26.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 26.0 or later.
- iPhone
- Languages
- English and Spanish
- Age Rating
16+
- 16+
- Frequent
Medical Treatment information
- In-App Purchases
Yes
- OB Datum Lifetime Pro $1.99
- Copyright
- © 2026 VLR Software LLC
