Understanding Surrogacy: A Complete Medical Guide
For couples who have exhausted other fertility treatments, or for whom pregnancy is medically impossible or dangerous, surrogacy can represent a profound and life-changing path to parenthood. The process is complex, emotionally layered, and requires careful coordination between medical teams, legal professionals, and the surrogate herself. This guide walks you through every stage of the surrogacy journey — from the initial decision to the moment you hold your baby — so that you can approach this path feeling informed, prepared, and supported.
What Is Surrogacy?
Surrogacy is an arrangement in which a woman carries and delivers a baby on behalf of another person or couple — known as the intended parents. There are two main types:
Gestational surrogacy: The surrogate has no genetic connection to the baby. An embryo created through IVF (using the intended mother's eggs fertilized with the intended father's sperm) is transferred into the surrogate's uterus. This is by far the most common form of surrogacy today.
Traditional surrogacy: The surrogate's own egg is used, making her the genetic mother of the child. This form is rarely practiced today due to significant legal and emotional complexities.
The vast majority of surrogacy arrangements today are gestational, and this guide focuses primarily on that model.
Who Needs Surrogacy?
Surrogacy is typically recommended in situations where carrying a pregnancy is either impossible or poses serious medical risks. Common indications include:
Absence of the uterus — either congenital (Mayer-Rokitansky-Küster-Hauser syndrome, also known as MRKH) or following a hysterectomy
Repeated implantation failure — multiple failed IVF cycles with good-quality embryos despite thorough investigation
Recurrent pregnancy loss — multiple miscarriages that cannot be adequately treated
Significant uterine abnormalities — such as severe Asherman's syndrome or structural anomalies that cannot be corrected surgically
Serious medical conditions — such as severe heart disease, kidney disease, or other systemic illnesses that make pregnancy life-threatening for the intended mother
Finding a Surrogate
Finding the right surrogate is one of the most important steps in the process. Surrogates may be found through:
Specialized surrogacy agencies, which screen and match surrogates with intended parents
Fertility clinics with established surrogate networks
Personal connections — a friend or family member who volunteers to carry
Regardless of how a surrogate is found, she must undergo a thorough screening process before any medical procedures begin.
Medical Screening of the Surrogate
Before a surrogate is approved, she will undergo extensive evaluation to ensure she is physically and psychologically suited for the role. This includes:
Physical Evaluation
Complete medical history and physical examination
Review of prior obstetric history — surrogates are typically required to have had at least one uncomplicated pregnancy and delivery
Blood tests: complete blood count, infectious disease screening (HIV, hepatitis B and C, syphilis, CMV, rubella immunity), blood type and Rh factor
Uterine assessment: hysteroscopy or saline sonogram (SIS) to confirm a healthy uterine cavity
Hormonal testing
Review of medications and lifestyle factors
Psychological Evaluation
Standardized psychological testing
In-depth interview with a licensed mental health professional experienced in third-party reproduction
Assessment of her support system — partner, family, and social network
Exploration of her motivations and expectations
Intended parents may also be asked to undergo psychological counseling as part of the preparation process. This is not a formality — it helps all parties align expectations, communicate openly, and prepare emotionally for the journey ahead.
Legal Agreements
Before any medical treatment begins, a comprehensive legal contract must be drafted and signed by all parties. This agreement covers compensation (in commercial arrangements), medical decision-making, what happens in the event of multiples or fetal anomalies, parental rights, and many other contingencies. Each party should be represented by their own independent legal counsel. The legal landscape for surrogacy varies significantly by country and region, so working with an attorney who specializes in reproductive law is essential.
The Medical Process: Step by Step
Step 1: Embryo Creation
The intended mother undergoes a standard IVF cycle, which includes ovarian stimulation with injectable hormones, egg retrieval under sedation, and fertilization of the eggs in the laboratory. The resulting embryos are cultured in the laboratory, typically to the blastocyst stage (day 5 or 6). In some cases, preimplantation genetic testing (PGT) may be performed before an embryo is selected for transfer.
Step 2: Synchronization and Surrogate Preparation
The surrogate's uterus is prepared to receive the embryo through a hormonal protocol. This typically involves:
Estrogen supplementation — oral, transdermal (patch), or injectable — to thicken the uterine lining
Progesterone supplementation — vaginal suppositories, intramuscular injections, or a combination — to prepare the lining for implantation
Regular ultrasound monitoring to assess endometrial thickness and appearance
A lining of at least 7–8mm with a trilaminar (triple-line) pattern is generally considered optimal for embryo transfer.
Step 3: Embryo Transfer
Once the surrogate's lining is ready, the embryo transfer takes place. This is a straightforward outpatient procedure, similar to an intrauterine insemination (IUI). A thin catheter is guided through the cervix into the uterine cavity, and the embryo is gently deposited. No anesthesia is required, and the procedure takes only a few minutes. The surrogate rests briefly afterward and can typically resume normal activities the same day.
Step 4: The Two-Week Wait
Approximately ten to fourteen days after the embryo transfer, a blood pregnancy test (beta-hCG) is performed. If positive, the levels are monitored over the following days to confirm a viable pregnancy. This period is emotionally intense for both the surrogate and the intended parents.
Step 5: Pregnancy Monitoring
Once pregnancy is confirmed, the surrogate continues progesterone supplementation (and sometimes estrogen) through approximately the tenth to twelfth week of pregnancy, until the placenta takes over hormone production. She is then transitioned to the care of her OB-GYN for routine prenatal care. The surrogate attends all prenatal appointments, though intended parents are often present or connected via telehealth. Communication protocols between the surrogate and intended parents should be established clearly at the outset.
Step 6: Delivery
The surrogate delivers at a hospital like any other obstetric patient. In most surrogacy arrangements, the intended parents are present in the delivery room. Legal processes to establish parental rights — which vary by jurisdiction — should be completed before or shortly after birth, so that the intended parents are recognized as the legal parents on the birth certificate.
Success Rates
Success rates in surrogacy are generally favorable, in large part because the embryos used are often preimplantation genetic tested, and because the surrogate has a proven uterine capacity. Per-transfer live birth rates using euploid (chromosomally normal) blastocysts in a gestational surrogate typically range from 50–70%, though individual results vary based on embryo quality, the surrogate's uterine health, and other factors.
Emotional Considerations
The surrogacy journey is emotionally complex for everyone involved. Intended parents often carry the weight of a long fertility journey before arriving at this point, and the experience of not carrying one's own pregnancy can bring up profound feelings of grief, gratitude, vulnerability, and joy — sometimes all at once. Building a relationship of trust, respect, and open communication with your surrogate is one of the most valuable things you can do throughout this process. Many intended parents and surrogates describe their bond as one of the most meaningful relationships of their lives.
A Note on Halachic Considerations
While this article has focused on the medical dimensions of surrogacy, it is important to note that surrogacy raises significant and nuanced questions in Jewish law — including questions of maternity, lineage, conversion requirements, and more. These are not questions to navigate alone. PUAH has decades of experience guiding couples through the halachic complexities of surrogacy, in consultation with leading poskim. We warmly encourage any couple considering this path to be in touch with us so that your journey can proceed with both medical and halachic clarity and confidence.