Before a surrogate can be matched with intended parents and before any embryo transfer is attempted, she must pass a structured medical screening process. This is not a formality. It is a clinical gatekeeping stage designed to protect the health of the surrogate, the viability of the pregnancy, and the wellbeing of the child. Understanding what that screening covers helps intended parents ask informed questions and set realistic expectations from the outset.
The precise protocol varies by country, clinic, and the policies of the agency coordinating the programme. However, there is a broadly accepted standard of care that reputable clinics follow. The overview below reflects that consensus. For country-specific variations, see our destinations guide.
Screening typically begins long before any blood is drawn. A reproductive specialist or a designated clinic nurse will conduct a detailed health history interview. This covers:
A general physical examination follows, assessing blood pressure, weight, and overall health. Most programmes require a surrogate to fall within a specified BMI range — typically 18 to 30, though this varies — because BMI outside that range is associated with higher obstetric risk. A surrogate who does not meet baseline physical criteria at this stage will generally not proceed to further testing.
The uterus must be capable of supporting a healthy pregnancy to term. The gynaecological workup is therefore central to the screening protocol and usually includes the following.
A transvaginal or abdominal ultrasound examines the uterine cavity, the thickness and texture of the endometrial lining, and the presence of any structural abnormalities. Fibroids, polyps, a septate uterus, or adhesions can all affect implantation and pregnancy outcomes, and their presence does not automatically disqualify a surrogate, but it does require careful clinical review.
Many clinics go further than a standard ultrasound and carry out a hysteroscopy — a direct visual inspection of the uterine cavity using a thin camera — or a sonohysterogram, in which saline is introduced to the cavity to improve ultrasound imaging. These procedures provide a more detailed picture of the uterine environment than external scanning alone.
An up-to-date cervical smear is required. Any abnormal result must be investigated and resolved before the programme can proceed.
Infectious disease screening protects all parties. The panel tested is broad and, as of writing, standard practice at reputable clinics includes:
A positive result for a transmissible infection is typically disqualifying, at least until the condition is successfully treated or, where relevant, re-tested over an appropriate window period. The surrogate's partner or co-habitant is also screened for key infectious diseases at many programmes, given the risk of transmission prior to and during early pregnancy.
A comprehensive blood panel assesses the surrogate's general physiological health and identifies conditions that may complicate pregnancy. This usually includes:
The psychological assessment is as important as the physical one, yet it is the element that intended parents sometimes underestimate. A qualified psychologist — ideally one with specific experience in reproductive medicine — conducts a structured interview and may administer standardised questionnaires.
The evaluation explores the surrogate's motivations, her understanding of what the arrangement entails, her support network, how she has discussed the arrangement with her own children if she has them, and her anticipated emotional experience of handing over the baby after birth. It also screens for underlying psychological vulnerability that might not have been evident from the health history alone.
This is not a pass-or-fail test in the same way as a blood result, but a clinician who identifies significant concerns will advise against proceeding. Reputable programmes treat this recommendation as binding. See our how it works guide for more on the matching and screening timeline.
Although this sits at the intersection of medical and legal process, most clinic protocols include a formal confirmation that the surrogate meets statutory eligibility criteria applicable in the jurisdiction where the treatment will take place. As of writing, those criteria vary considerably between countries — some require the surrogate to have completed her own family, others specify minimum age thresholds beyond the standard age of majority. Intended parents should confirm the current requirements with local legal counsel, as these rules change and cannot be summarised as fixed fact.
For a country-by-country comparison of eligibility rules and legal frameworks, our destinations guide provides a starting point, and our programmes section explains how these requirements interact with agency protocols.
It is worth being explicit about the limits of medical screening. Even a surrogate who passes every element of the process is not guaranteed to carry a pregnancy to term. Screening identifies and mitigates known risk factors; it cannot eliminate the inherent uncertainty of human reproduction. Implantation may fail, miscarriage can occur, and obstetric complications can arise in women with no prior indicators. Intended parents should approach screening as a rigorous risk-reduction measure, not as a guarantee of outcome.
Screening also does not assess the quality or genetic viability of the embryo itself, which is a separate clinical consideration addressed through the intended parents' own medical workup and, where appropriate, preimplantation genetic testing of embryos.
When reviewing a proposed programme, it is reasonable to ask the clinic or agency the following:
For a broader view of programme costs and what medical screening fees typically represent within total expenditure, see our costs guide.
Medical screening is not a bureaucratic hurdle. It is the clinical process through which a programme establishes that a surrogate can undertake this commitment safely, and through which intended parents can have reasonable confidence in the foundation of their journey.
This article is provided for informational purposes only and does not constitute medical or legal advice. Readers should seek independent clinical and legal guidance relevant to their specific circumstances.