Surrogate Medical Screening: Every Test Explained

The medical screening overview

Medical screening is the step between agency approval and entering the matching pool. It happens at the intended parents' fertility clinic — not your regular OB's office. The clinic may be in another state, which means you'll need to travel. Travel costs are reimbursed. It comes right after, or alongside, psychological screening, which looks at readiness rather than health.

Typical duration: 1-2 months total from first appointment to final clearance. Some tests can be done in one visit; others require follow-ups.

What gets screened

Comprehensive bloodwork — what they check for

Bloodwork is the biggest part of medical screening. Expect multiple vials drawn, and sometimes multiple visits. Tests include:

Infectious disease panel

• HIV 1 and 2 — disqualifying if positive
• Hepatitis B surface antigen — disqualifying if active infection
• Hepatitis C antibodies — active infection is disqualifying; a cleared past infection (RNA negative) may be acceptable, and the clinic's physician decides
• Syphilis (RPR) — treatable; not automatically disqualifying
• Chlamydia and gonorrhea — treatable; requires treatment before clearance
• Rubella immunity — if you're not immune, the clinic will counsel you; an MMR booster is a live vaccine, so it delays your cycle
• Varicella (chicken pox) immunity — usually expected; ask the clinic how they handle non-immunity
• CMV status — informational, not disqualifying

Hormone and fertility markers

• Thyroid (TSH, T3, T4) — needs to be well-controlled
• Progesterone baseline — for cycle timing
• Estradiol baseline — for cycle timing
• Prolactin — elevated levels can indicate issues
• FSH and LH — sometimes run, though they matter less for a carrier who contributes no eggs

General health markers

• Complete blood count (CBC) — checks for anemia, infection
• Comprehensive metabolic panel — kidney function, liver function, glucose
• Hemoglobin A1C — diabetes screening
• Blood type and Rh — for pregnancy planning
• Antibody screen — for potential Rh incompatibility

What isn't screened: your genetics

As a gestational carrier you contribute no DNA to the baby, so genetic carrier screening isn't part of a standard surrogate workup. That testing is done on the egg and sperm sources. If a clinic orders any genetic test on you, ask what it's for — a few run limited panels for conditions that affect pregnancy itself, not the embryo.

Uterine evaluation — the SHG or hysteroscopy

The clinic needs to confirm your uterus can successfully carry an embryo. This is done through one of two procedures:

Sonohysterogram (SHG)

A saline-infusion ultrasound. A thin catheter is inserted through your cervix and saline is injected into your uterine cavity while an ultrasound probe images the uterus. The saline expands the cavity so the clinic can see any fibroids, polyps, scar tissue, or structural issues clearly. Takes about 15 minutes. Mildly uncomfortable but not usually painful.

Hysteroscopy

A small camera on a flexible tube is inserted through your cervix to visually examine your uterine cavity. Takes about 20-30 minutes. Performed in the office or sometimes a surgical suite. Some clinics prefer this over SHG for a clearer view.

What they're looking for

• Normal uterine cavity shape
• No significant fibroids (small ones are usually fine)
• No polyps (if found, usually removed before clearance)
• No scar tissue (from C-sections or prior procedures)
• Adequate endometrial lining development

STI testing and pap smear

Standard STI panel: chlamydia, gonorrhea, syphilis, HIV, Hep B, Hep C. Any treatable STI found must be treated and confirmed cleared before you can proceed. HIV and active hepatitis infections are disqualifying.

Pap smear checks cervical health and HPV status. Abnormal pap results may require colposcopy or additional follow-up. A normal pap is required for clearance.

Drug screening

A urine drug screen typically checks for nicotine (cotinine), marijuana (THC), cocaine, methamphetamine, opioids, and other drugs; the exact panel varies by clinic. Any positive result stops the current cycle. Most agencies require a clean waiting period — often several months — before you can retest and reapply after a failed drug screen. Ask your agency for its exact policy.

Nicotine testing catches smoking, vaping, and chewing tobacco. Secondhand exposure rarely triggers a positive at standard cutoffs, but agencies do ask about smokers in the home and weigh that during review.

Most clinics and agencies treat marijuana as a disqualifier even in states where it's recreationally legal, and policies on past use vary — some agencies review it case by case, so answer honestly on your application. THC can show up on a urine screen for days after occasional use and for weeks with frequent use. If you've used recently, expect to fail the screen.

Physical exam

The physical exam confirms general health. Height, weight, and BMI are re-verified — if you were on the borderline for BMI at application, this is where it gets checked against the clinic's actual scale. Blood pressure is measured. Any visible signs of health issues are noted.

Heart and lung auscultation, abdominal exam, and standard physical check. Nothing surprising.

Pregnancy history review

The clinic wants your full pregnancy records. Expect to provide:

• Prenatal records from all prior pregnancies
• Delivery records (vaginal, C-section, complications)
• Any hospitalization records related to pregnancy
• Records of miscarriages or losses

The clinic is looking for patterns — were your pregnancies healthy? Any concerning complications? History of preterm labor? Gestational diabetes? Preeclampsia? Placenta previa?

Minor complications don't usually disqualify you. Severe complications (for example eclampsia, HELLP syndrome, or placental abruption) may — the clinic's physician makes that call based on your records.

Partner screening (if married or partnered)

If you're married or in a long-term relationship, your partner will also be screened for HIV and hepatitis. This follows FDA donor-eligibility rules for gestational carriers: sexual activity during the medical protocol could theoretically expose the embryo to an infection. A positive on your partner's screening doesn't disqualify you directly; the clinic adjusts the protocol instead — usually extra testing, timing rules, or abstinence requirements during the cycle.

What causes medical screening failures

Based on what partner agencies and surrogates describe, the reasons women fail medical screening fall into two groups. The first group is fixable — you address it and reapply. The second is usually permanent. We don't have hard data on how often each happens; treat this as a guide, not a ranking.

Fixable — reapply after addressing

• BMI on arrival is higher than reportedOne of the most common fixable failures agencies describe. Get to your target on a real scale before the visit.
• Positive drug screenA waiting period, then retest. Ask the agency for its policy.
• Uterine fibroids or polyps that need removalUsually a minor procedure, then re-evaluation.
• Thyroid not well-controlledAdjust medication with your doctor and retest.
• Abnormal pap requiring follow-upDelays clearance; rarely disqualifying on its own.

Usually permanent

• HIV or active hepatitis B or CDisqualifying under donor-eligibility screening rules.
• Severe uterine anomaliesDepends on severity; significant structural issues end eligibility.
• Severe complications in a prior pregnancyThe physician decides case by case; some histories are a firm no.

For the agency-side rules that apply before you ever reach the clinic, see surrogate requirements and what disqualifies you.

How to prepare for medical screening

• Gather all medical records beforehand. Prenatal, delivery, hospitalization, and primary care records.
• Stop using any drugs or alcohol well before — 90+ days is a safe margin. Marijuana especially — THC can stay detectable longer than most people realize.
• Get to your target BMI before the visit. Borderline BMI is the most common fixable reason agencies describe for failed screening.
• Schedule the visit for a time when you're well-rested and healthy. Don't show up with a cold — it can delay the process.
• Bring your partner if you're married or partnered. Partner screening is easier when it's done at the same visit.
• Drink plenty of water before bloodwork. Makes the draw easier.

Questions to ask at your screening appointment

• Which uterine evaluation do you use — SHG or hysteroscopy — and why?
• How and when will I get my results, and who else sees them?
• If something comes back abnormal, what's the retest policy and who pays for follow-ups?
• What BMI cutoff does this clinic use, measured on your scale?
• Does my partner need to be screened here, or can it be done locally?
• Which of today's results expire, and will I need to repeat anything before transfer?

Frequently asked questions