FAQs
GETTING STARTED
A mail-in sperm test. You collect a sample, preserve it with SpermShield, post it back, and view your results in your online dashboard, typically within 3–5 working days from posting.
Jack gives you sperm health results and context in your online dashboard, for informational use only. It does not provide a diagnosis or medical advice.
Sperm testing gets treated like something clinical, awkward, or only worth doing when things go wrong. We wanted a name that made it feel more normal. Jack felt right.
Anyone with sperm who wants a clear baseline, or to track change over time, without a clinic visit. Common reasons include planning ahead, checking in periodically, or tracking change during lifestyle shifts (like diet changes, intensive training, or prolonged heat exposure).
Yes. Anyone can buy a kit for someone else.
The person who registers the kit is the one who creates the account and receives results, regardless of who originally bought it.
The buyer is not notified when a kit is registered and does not have access to the results or account.
USING THE SPERM TEST KIT
A collection tube and funnel, SpermShield preservative, prepaid return packaging, and a unique kit ID and PIN to register your kit securely to your online account, where you can access your results.
Our preservative fluid SpermShield™ has a shelf life of four months. The expiry date is printed on the SpermShield™ vial. If you want to test after this expiry date, contact us and we'll send you a free replacement vial of SpermShield™.
We recommend 2-5 days of abstinence (no ejaculation from either masturbation or sexual activity) for the most representative sample. If you don’t, we’ll still conduct your test, but the result is a snapshot of that moment, and not abstaining is a factor that can change your results.
We strongly recommend you do not. Many lubricants (even ones marketed as 'sperm friendly') and saliva can affect and interfere with your test results.
This is critical. It’s how we estimate motility at collection and it’s entered during kit registration in your dashboard. If the time and date are missing, we may not be able to report your Estimated Original Total Motility.
No. Keep the kit at room temperature in a cool, dry place out of direct sunlight. Do not refrigerate or freeze any components at any point during the process.
It happens. If you miss the funnel, don’t manage to collect all the ejaculate, forget to abstain, or realise it’s not Sunday to Wednesday for posting, contact us before you post. We’ll tell you what to do next and, if needed, we’ll replace the relevant components free of charge so you can re-collect.
If there’s a transit issue, or a sample can’t be processed reliably for any reason, we’ll tell you clearly and arrange the next step to try and make it right, usually a replacement kit so you can re-test or a full refund.
POSTING & DELIVERY
Royal Mail Tracked48 with no signature required, in plain packaging with no visible branding.
Free. Royal Mail Tracked delivery to your address is included.
Your return envelope is also prepaid, so once you’ve collected your sample, you can simply drop it into any postbox.
Once you've collected a sample, close the test tube by screwing on the lid tightly, place it in the prepaid return packaging, and post it at any Royal Mail postbox (or Post Office if you'd prefer that way). Simple.
Sunday to Wednesday only. Post on the same day that you collect your sample.
That’s the window that gets your sample to our lab in time for reliable analysis. If you post Thursday to Saturday, it’s likely to arrive too late at our lab for us to test.
If anything happens in transit that could affect interpretation, we will flag it clearly in your results.
If your sample arrives too late to test reliably, or cannot be processed with confidence for any reason, we will let you know and contact you to arrange the next step, usually a free replacement kit so you can re-test.
Very. There’s no personal or personally identifiable information anywhere on or in the returns envelope you post to our lab.
Please email us if we have not already been in touch. Both delivery to you and return postage to our lab are tracked, so we can check what has happened and arrange a replacement kit if needed.
Not currently. Jack is a service only available in Great Britain. Please note that for regulatory reasons, our service currently does not cover Northern Ireland.
RESULTS
In your online dashboard. You create an account and can then register your kit using the unique kit ID and PIN. Your past results stay there too, so you can track changes over time and register more kits to your account.
We aim to get your results to you as quickly as possible after you post your sample. This is based on largely dependent Royal Mail delivery times to our lab, but it can be in as little as 2 days after you post a sample or up to 4 days.
Jack gives you clearly labelled results. We show what’s measured directly and what’s estimated, plus the context to interpret it. For the methodologies we use and the accuracy of each, see Our Science page.
- Volume (amount of sample)
- Count (total sperm in the sample)
- Concentration (sperm per ml)
- Estimated Original Total Motility (total motility at collection, estimated)
- Estimated Morphology Status (morphology reported as a status)
Our Sperm Test is not the same as a semen analysis at a clinic. Clinics analyse a fresh sample quickly, often with in-person collection. Jack is built for postal return, so we preserve your sample, and where the journey affects what can be measured fresh, we account for it and label it clearly.
All results (apart from Estimated Morphology Status) are classified into a band: Low, Borderline Low, Below Average, Above Average, or High. This shows where you sit compared to a population reference range established by the World Health Organisation. Put simply, how your result compares to other men in general.
A LOW result means that parameter sits in the lowest band of the reference range Jack uses for context (aligned to the WHO lower reference limit).
It’s not a “fertile vs infertile” cut-off, it’s a signal that this part of your result is highly likely to be lower than most men in the reference group. Many people use a LOW result as a prompt to retest (to see if it repeats) and, if it’s relevant to them, discuss it with a GP or specialist for further clinical context.
We don't present a specific number in this band because a figure here could be over-interpreted as a clinical diagnosis. The LOW band can often be the trigger for further clinical investigations. It's important to note that this does not represent a limit between fertile and infertile men.
'BORDERLINE LOW' means you're close to the LOW threshold. However, with natrual variation between samples, this result could reasonably sit either side of the line. We call it BORDERLINE LOW rather than make a definitive call that the data doesn't support.
Total motility is the percentage of sperm that are moving in any way. It declines over time. Because your sample travels by post, we can’t measure it fresh. We estimate total motility at collection using your logged collection time, our lab timings, and proprietary SpermShield decay data. Your estimate of what your total motility was at the time of production is what's shown in your report.
Morphology is the shape of sperm cells and the proportion that are 'normally' formed. Clinic assessments use a manual method on a fresh sample, reported as a percentage of normal forms. Our approach differs. We use a proprietary estimation method, and we report a simple Above or Below threshold benchmarked against the WHO's 4% "normal forms" reference point.
Why not a percentage score? Because morphology is the most subjective parameter in andrology, variation between expert assessors is high, and a precise-looking number implies a certainty the field itself doesn't have. We'd rather give you a clear classification you can trust.
Yes. Sperm regenerates on a roughly 74-day cycle, so lifestyle and general health changes can show up in later results. Where there’s an underlying medical or biological cause, that’s something a clinician can explore. Jack is designed to help you build a baseline and see changes, not to diagnose, prescribe treatment. Nor do we give medical advice or are we a substitute for medical advice from a healthcare professional.
Yes. You can download a PDF from your online results dashboard that is designed specifically for healthcare professionals.
How your doctor uses it is up to them and will depend on their own clinical judgement. Because Jack uses a different methodology from a standard semen analysis, healthcare professionals are not obliged to accept our results in place of their own assessment.
No. Sperm parameters vary naturally between samples and over time. That’s one reason some people test more than once, to see a pattern rather than rely on a single snapshot.
There’s a 2-quarter minimum commitment (2 tests) After that, cancel anytime.
We send a new kit every three months. That timing lines up with sperm’s cycle, so your next result is a cleaner comparison. Kits can be kept at home for up to six months if you need flexibility. You can manage delivery details in your account where all your past results are stored, or contact us for help.
PRIVACY & SECURITY
Only the account holder who registered the kit. Results are shown in your secure online dashboard.
Each kit has a unique ID and PIN. You register it yourself, and your results are linked to your account through that process.
No personally identifiable information is stored on the kit itself. Until the kit is registered, it cannot be linked back to you. Accounts are protected using secure two-factor authentication, and only the registered account holder can access the results.
Your dashboard is encrypted. Login is protected, and kit registration requires a unique ID and PIN. See our Privacy Policy for details.
No.
Samples are destroyed securely as medical waste after analysis, in line with our lab protocols and UK regulations.
Yes. Email hello@jackfertility.co.uk and we’ll handle your request in line with GDPR.
We may use anonymised, aggregated data to improve our service and support research, and nothing used in this way can identify you personally. This is entirely optional and you can opt out. See our Privacy Policy for details.

