How to screen a known donor: medical questions to ask before an arrangement

This article is a companion to our guide on legal agreements in known donor arrangements. Where that article covered the legal framework — parentage, parental responsibility, the HFEA 2008 framework — this one covers the medical questions that recipients and donors should work through together before any arrangement proceeds.

This is written for people considering a known donor arrangement, not for clinic-based anonymous donation, which has a formal screening framework administered by the clinic. In a known donor arrangement, the responsibility for screening falls on the parties themselves, and the consequences of inadequate screening can be severe — both for the child's health and for the legal position of all parties.

Why medical screening matters more in known donor arrangements

In a licensed clinic, sperm donors undergo rigorous screening before being accepted onto the donor register. The HFEA requires clinics to screen for:

• Infectious diseases: HIV 1 and 2, hepatitis B and C, syphilis, gonorrhoea, chlamydia, and HTLV-1/2. Screening is repeated at quarantine and at 180 days, with samples held in quarantine between tests.
• Genetic conditions: Chromosome karyotype analysis, cystic fibrosis (CFTR) carrier status, and screening for conditions with elevated prevalence in the donor's ethnic background (e.g., Tay-Sachs in Ashkenazi Jewish populations, sickle cell in West African populations, thalassaemia in Mediterranean populations).
• General health: Mental health assessment, substance use assessment, and a review of family medical history going back three generations.

In a known donor arrangement, none of this is automatically done. The parties can arrange these screenings privately — and they should — but the initiative falls on them. If the arrangement proceeds without screening and a child is conceived with an undiagnosed infection or a carrier status for a genetic condition, the consequences are borne by the child and by the recipient who will become the parent.

The screening framework: what to ask, what to test, what to document

Below is a framework that mirrors the HFEA's clinic screening protocol, adapted for private arrangements. Each section lists what to discuss, what documentation to request, and what the results mean.

1. Infectious disease screening

This is the most critical screening. A full STI panel should be completed within 30 days of the arrangement beginning, and should include:

The 180-day retest is not optional. HIV, Hepatitis B, and Hepatitis C all have window periods during which infection is present but undetectable. A negative test at day 0 does not mean the donor is uninfected — it means they were uninfected as of the start of the window period. The HFEA requires quarantine with retesting at 180 days precisely because of this. In a private arrangement, the same protocol should be followed.

Testing is available through the NHS (free, with a GP referral) or through private sexual health clinics. The cost of a full panel at a private clinic in the UK is approximately £350-£600. Both parties should be tested — not just the donor — because sexually transmitted infections can be transmitted in either direction during natural insemination.

2. Genetic carrier screening

Genetic screening is not about eugenics or selecting for desirable traits. It is about identifying whether the donor is a carrier for a recessive genetic condition that, combined with the recipient's carrier status, could result in a child with a severe genetic disease.

The standard panel is the "expanded carrier screening" (ECS) panel, which screens for the conditions recommended by the American College of Medical Genetics (ACMG) and the UK Genomics England carrier screening programme:

• Cystic fibrosis (CFTR) — carrier frequency approximately 1/25 in Northern European populations
• Spinal muscular atrophy (SMN1) — carrier frequency approximately 1/50
• Sickle cell disease (HBB) — carrier frequency varies by population, highest in West African, Mediterranean, and South Asian populations
• Thalassaemia (HBA1/HBA2/HBB) — carrier frequency highest in Mediterranean, South Asian, and Southeast Asian populations
• Tay-Sachs disease (HEXA) — carrier frequency approximately 1/27 in Ashkenazi Jewish populations
• Fragile X syndrome (FMR1) — premutation carrier screening

The screening involves a blood draw or saliva sample and is processed by a laboratory accredited by the UK Accreditation Service (UKAS). The cost in the UK is approximately £400-£800 depending on the panel scope. Companies like GeneUK and Counsyl offer direct-to-consumer carrier screening, though the results should be interpreted with a genetic counsellor.

3. Family medical history — three generations

The donor should provide a family medical history going back three generations (parents, grandparents, and where known, great-grandparents). This should include:

• Age and cause of death for all relatives
• Known genetic conditions, chromosomal disorders, or congenital anomalies
• History of miscarriage or stillbirth (particularly recurrent pregnancy loss, which can indicate chromosomal translocation carriers)
• Mental health conditions (schizophrenia, bipolar disorder, major depression) — these have strong heritable components
• Substance use history
• Reproductive history, including any known prior donor-conceived children

This information is not about excluding the donor — it is about understanding the full picture of what the child's genetic inheritance might include. A donor with a family history of cardiovascular disease is not disqualified; a donor who conceals a family history of Huntington's disease is creating a situation where the recipient cannot make an informed decision.

4. Age and fertility markers

For male donors, the relevant markers are:

• Semen analysis: Volume, concentration (sperm count per mL), motility (total motility and progressive motility), morphology (strict criteria), and vitality. A normal analysis per WHO 6th edition thresholds: volume ≥1.4 mL, concentration ≥16 million/mL, total motility ≥42%, progressive motility ≥30%, normal morphology ≥4%.
• Age: Advanced paternal age (over 45) is associated with increased risk of de novo mutations, autism spectrum disorder, and schizophrenia. The risk increases incrementally — a 50-year-old donor has approximately 2x the baseline risk of new mutations compared to a 30-year-old donor.
• Lifestyle factors: Smoking (tobacco and cannabis) reduces sperm count and motility by approximately 30%. Alcohol consumption above 14 units/week increases DNA fragmentation. Anabolic steroid use causes profound suppression of spermatogenesis, sometimes permanent.

A semen analysis costs £150-£300 at a private clinic. The donor should provide a recent result (within 90 days) before any arrangement proceeds.

5. Mental health and psychological assessment

The HFEA requires clinics to assess donors' mental health before accepting them onto the register. In a private arrangement, the parties should consider:

• Whether the donor has a history of psychiatric conditions that might affect their judgement or their ability to understand the consequences of donation
• Whether the donor is acting under coercion (financial pressure, partner pressure, or pressure from a recipient)
• Whether the donor has thought through the possibility of future contact with a child conceived using their genetic material, and how they would respond to that contact
• Whether the recipient has considered how they would explain the donor's role to the child, and whether the donor will have any role in the child's life

These are not medical questions in the traditional sense, but they are questions that a fertility counsellor would explore in a clinic setting. The British Infertility Counselling Association (BICA) offers counselling sessions for £80-£150 per session, and I recommend that both parties attend at least one session before proceeding.

Documentation: what to keep, what to share

Every screening result, every medical document, and every conversation about the arrangement should be documented and stored. In the event of a dispute — between the donor and the recipient, or between either party and a future child who seeks information about their conception — the documentation is what protects everyone.

The documentation package should include:

1. STI panel results — both parties, dated, with laboratory reference numbers
2. Genetic carrier screening results — both parties, with genetic counselling report
3. Semen analysis — donor, within 90 days of the arrangement
4. Family medical history form — donor, three generations, signed and dated
5. Written agreement — the legal agreement covering the arrangement (see our legal agreements article for the framework)
6. Counselling attendance confirmation — both parties, from a BICA-registered counsellor

All documents should be stored in two formats: an encrypted digital copy (e.g., a VeraCrypt volume or a properly configured cloud storage account with two-factor authentication) and a physical copy in a fireproof safe. The recipient and donor should each retain complete copies.

What to do when screening reveals something

Screening exists to find things. If a test comes back positive, that is the system working — not a reason to panic. The response depends on what is found:

Infectious disease (active)

If the donor tests positive for an active infection (chlamydia, gonorrhoea, syphilis), the infection should be treated and resolved before any arrangement proceeds. For HIV, Hepatitis B, or Hepatitis C, the donor should be permanently disqualified from natural insemination — the risk of vertical transmission is too high, and the legal and medical consequences of infecting a recipient (and potentially a child) are severe.

Genetic carrier status

If the donor is a carrier for a recessive condition, the next step is to test the recipient. If the recipient is not a carrier for the same condition, the risk of an affected child is the population baseline risk (low). If both parties are carriers, the risk is 25% per pregnancy — and the parties should make an informed decision about whether to proceed, use a different donor, or pursue IVF with pre-impleneration genetic testing (PGT-M).

Fertility issues

If the donor's semen analysis shows subfertility (oligozoospermia, asthenozoospermia, teratozoospermia), this does not preclude donation but it does reduce the likelihood of conception per cycle. The parties should discuss whether the arrangement is practical, or whether fertility treatment (IUI, IVF) with the donor's genetic material might be more appropriate.

The cost of proper screening

Proper screening is not cheap. The approximate costs in the UK, as of 2026, are:

These costs are real and they are not optional. An arrangement entered into without screening is not a "natural" or "frugal" arrangement — it is a negligent one. The cost of a child with a severe genetic condition, or a recipient with an STI acquired from a donor, is orders of magnitude higher.

The legal framework around screening

Under the HFEA 2008, a donor who donates through a licensed clinic is protected from parentage claims and is not legally the parent of the child. A known donor who conceives through sexual intercourse is, as a matter of law, the parent — with all the rights and responsibilities that attach to parentage. This means:

1. The donor is legally the father and can be named on the birth certificate
2. The donor has parental responsibility (or can acquire it through agreement or court order)
3. The donor is financially responsible for the child until the child reaches 18 — the Child Maintenance Service can pursue the donor for child support
4. The donor cannot waive these responsibilities through a private agreement — any agreement that purports to do so is unenforceable under the HFEA 2008

A properly drafted legal agreement cannot change the parentage outcome (the donor is the legal father regardless), but it can document the parties' intentions regarding contact, financial arrangements, and the donor's role in the child's life. This documentation is valuable if there is a future dispute — and it is essential if the parties ever need to go to family court.

Conclusion: screening is the foundation, not an obstacle

The people who enter known donor arrangements are, in most cases, acting from a desire to help someone become a parent. That impulse is not in question. What is in question is whether the parties have taken the time to understand the medical, legal, and emotional consequences of what they are doing — and whether they have the information they need to make good decisions.

Proper medical screening is not an obstacle to the arrangement. It is the foundation on which the arrangement is built. A donor who refuses screening is not a donor who is being "natural" or "trusting" — they are a donor who is asking the recipient to accept unknown medical risk on behalf of a future child, and that is not a reasonable ask.

Work through the framework in this article with your donor. Get the tests. See the counsellor. Draft the agreement. And if any of those steps reveals something you didn't expect — that is the system working exactly as it should.