510(k) · Cleared
ClearedNatural Cycles
Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly
Natural Cycles Nordic AB · PYT Device, Fertility Diagnostic, Contraceptive, Software Application
Cleared on Mar 21, 2025 as substantially equivalent to K231274 (Natural Cycles Nordic AB, 2023) after a 24-day review. Its family tree reaches back 3 generations to 2018.
- Decided
- Mar 21, 2025
- Review
- 24 days
- Class
- Class II
- Product code
- PYT
- Recalls
- None
- Predicates
- 1
Its longest line of descent runs back 3 generations to DEN170052 (2018). No later device cites it as a predicate yet.
View FIG. 1 as a table
Line of descent and top descendants
Sources: FDA 510(k) database (decision fields), the FDA summary (predicates and indications), FDA recall and enforcement reports, and MAUDE; processed by 510(k) Report. Verify on FDA.gov · Methodology and accuracy.
Planning a device in PYT? A 510(k) Report weighs predicate choices, recall history and review times for a new device like this one.
Top candidate predicates for a new PYT device
- #1 K231274 Natural Cyclesscore 15.2 · 2 generations · no Class I recall
- #2 Held for the reportin the report
- #3 Held for the reportin the report
What was it cleared against? (1)
Devices the submitter claimed this one is substantially equivalent to (*), and reference devices cited for a specific test or feature (†), as written in the FDA summary.
| Type | Number | Device | Decided |
|---|---|---|---|
| * | K231274 | Natural CyclesSummary page 5…21 CFR 884.5370 Number: Product Code: PYT (Device, fertility diagnostic, contraceptive, software application) Predicate Device: K231274 Natural Cycles The predicate device has not been subject to a design-related recall. Device… | 2023 |
What descends from it?
No later submission names this one as a predicate yet.
Has anything in its family been recalled? (0 Class I)
No FDA recall names this device.
No ancestor or descendant has a Class I recall.
What does this lineage say?
- The line of descent spans 7 years and passes through 1 company; a new generation was cleared every 2.2 years on median.
- None of the 3 ancestors has a recall.
- 2 other devices also cite its predicate K231274.
How does its category compare?
All PYT devicesPYT Device, Fertility Diagnostic, Contraceptive, Software Application: FDA decisions, review times, recalls and adverse event reports over 20 years. 2025, this device’s year, is highlighted.
FDA decisions per year · PYT
1in 2025
2026 to Oct 25, outlined.
Median 510(k) review, days · PYT
Too few PYT 510(k)s in any year since 2007 to give a median.
Recalls per year · PYT
No recall names PYT since 2007.
Adverse event reports per year · PYT
2in 2023
MAUDE reports naming product code PYT, not matched to any one device; reports are not rates.
View these four charts as a table
| Year | Decisions | Median 510(k) review, days | Recalls (Class I) | MAUDE reports |
|---|---|---|---|---|
| 2007 | 0 | — | 0 | 0 |
| 2008 | 0 | — | 0 | 0 |
| 2009 | 0 | — | 0 | 0 |
| 2010 | 0 | — | 0 | 0 |
| 2011 | 0 | — | 0 | 0 |
| 2012 | 0 | — | 0 | 0 |
| 2013 | 0 | — | 0 | 0 |
| 2014 | 0 | — | 0 | 0 |
| 2015 | 0 | — | 0 | 0 |
| 2016 | 0 | — | 0 | 0 |
| 2017 | 0 | — | 0 | 0 |
| 2018 | 1 | — | 0 | 0 |
| 2019 | 0 | — | 0 | 1 |
| 2020 | 0 | — | 0 | 0 |
| 2021 | 2 | — | 0 | 0 |
| 2022 | 0 | — | 0 | 0 |
| 2023 | 1 | — | 0 | 2 |
| 2024 | 1 | — | 0 | 0 |
| 2025 | 1 | — | 0 | 0 |
| 2026 | 1 | — | 0 | — |
What is it indicated for?
Natural Cycles is a stand-alone software application, intended for women 18 years and older, to monitor their fertility.
Natural Cycles can be used for preventing a pregnancy (contraception) or planning a pregnancy (conception).
Indications for use read by OCR from a scanned FDA summary, so letters may be misread. Check the PDF before quoting it.
https://510kreport.com/device/K250561 · printed Nov 6, 2026
Cite this page
510(k) Report. “K250561: Natural Cycles.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 6, 2026. https://510kreport.com/device/K250561
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Record history
- FDA decision record loaded May 2, 2026
- Summary read Oct 13, 2026 (extraction version 9eaa42aa01ed)
- Lineage and recalls computed Nov 3, 2026
- Page last updated Nov 3, 2026