In gestational surrogacy, the surrogate takes hormone medications for several weeks before an embryo transfer so her uterus is ready to receive the embryo. The usual regimen includes birth control pills, a drug that suppresses ovulation (often Lupron), estrogen, and progesterone, sometimes with antibiotics, a steroid, or low-dose aspirin. The reproductive endocrinologist sets the exact plan. This guide explains each step in plain terms, so you know what is being asked of the woman carrying your child and which questions to put to your clinic.
TL;DR
- Surrogacy medications do not make the surrogate fertile. They synchronize her uterine lining with the embryo's age so the transfer can work.
- A typical sequence is birth control pills, then ovulation suppression, then estrogen, then progesterone. Doses and drugs vary by clinic and by patient.
- Progesterone is usually the longest-running medication and often continues into early pregnancy, until the clinic says to stop.
- Side effects such as bloating, mood changes, and injection-site soreness are common. Anything severe should be reported to the clinic at once.
- Once pregnancy is confirmed, prenatal care follows the surrogate's own obstetric team, with intended parents involved as the agreement allows.
Table of Contents
- Why a surrogate takes medication at all
- The usual medication sequence, step by step
- Other medications you may hear about
- Side effects and when to call the clinic
- What intended parents should ask the clinic
- Prenatal care during surrogacy
- Our perspective on medication in surrogacy
- Working with a team that explains each step
- FAQ
- Sources
Why a surrogate takes medication at all
In gestational surrogacy, the embryo is created through IVF using the intended parents' gametes or donor gametes, and the surrogate has no genetic link to the child. ACOG describes gestational surrogacy as a form of family building that lets individuals or couples become parents when carrying a pregnancy is biologically impossible or medically contraindicated. If you want the broader picture first, our guide to what surrogacy is covers the basics.
The surrogate does not need stimulation to produce eggs, because her own eggs are not used. What she needs is a uterine lining that is thick, receptive, and timed to the embryo's development. This is the same approach used in frozen embryo transfer cycles and egg donation recipient cycles. Medication replaces the natural hormonal rhythm of her cycle with a controlled, predictable one.
Control matters for a practical reason. In an international or multi-clinic arrangement, the embryos, the surrogate, and the intended parents' travel plans all need to line up. A medicated cycle lets the medical team set the transfer date in advance. You can read how this fits into the larger process in our article on how IVF powers the Colombia surrogacy journey.
The usual medication sequence, step by step
No two protocols are identical. The reproductive endocrinologist chooses drugs, doses, and timing based on the surrogate's medical history, her response to earlier cycles, and clinic practice. The sequence below is the common pattern, not a prescription.
Step 1: Birth control pills
After the surrogate is medically cleared, the cycle often begins with oral contraceptives. They quiet her natural cycle and allow the clinic to schedule the start of the process. They also let the team coordinate the surrogate's timeline with the embryo's availability.
Step 2: Ovulation suppression with Lupron
Lupron (leuprolide) is a GnRH agonist. It prevents the surrogate's body from ovulating on its own, which could disrupt the timed cycle. One widely cited clinical protocol for embryo recipients describes a standard regimen in which the pill is overlapped with 0.5 mg (10 units) of Lupron daily for 3 to 5 days before the pill is withdrawn. Your clinic may use a different dose or a different suppression strategy, and some protocols skip this step.
Lupron is injected under the skin with a small needle. Most surrogates are trained to give it themselves or have a nurse or partner assist.
Step 3: Estrogen to build the lining
Estrogen, given as tablets, skin patches, or injections, thickens the endometrium. The clinic monitors progress with ultrasound, measuring the lining, and with blood tests for estradiol levels. If the lining is slow to develop, the doctor can adjust the dose or route.
Patches and tablets are usually daily or every few days. Injectable estradiol is typically given less often but requires an intramuscular shot.
Step 4: Progesterone to prepare for implantation
Once the lining is ready, progesterone is added. It changes the lining from a growth phase to a receptive phase, and the start date is counted back from the transfer date according to the embryo's stage. Progesterone comes in several forms:
- Intramuscular injection in oil. The FDA label for progesterone injection specifies intramuscular use only, and the oil-based injection is given deep into muscle, usually in the upper buttock.
- Vaginal suppositories, inserts, or gel. These are often used alone or alongside injections.
- Oral capsules. Less common as the sole source, but sometimes included.
Progesterone is often the medication that surrogates find most demanding, because daily injections can leave soreness and lumps at the site. Warm compresses, rotating sides, and gentle massage are common comfort measures that a nurse can demonstrate.
Step 5: Transfer and early-pregnancy support
After the embryo transfer, the surrogate continues estrogen and progesterone. A pregnancy blood test follows about ten days after transfer, depending on clinic policy. If it is positive, the medications continue until the doctor decides the placenta can sustain the pregnancy on its own. The surrogate should never stop on her own. That decision belongs to the clinic.
Other medications you may hear about
Beyond the core hormones, a surrogate's plan may include supporting drugs. Whether they are used depends on the individual.
| Medication | Why it may be prescribed |
|---|---|
| Antibiotics (for example doxycycline) | Prevent low-grade pelvic infection before the cycle, at the physician's discretion |
| Low-dose aspirin | Sometimes used to support uterine blood flow, based on clinic protocol |
| Corticosteroids (for example methylprednisolone) | Used by some clinics around transfer |
| Prenatal vitamins with folic acid | Started before pregnancy and continued throughout |
Treat this list as a map of what you might hear, not as medical advice. The evidence for some adjunct drugs is debated, and clinics differ. Ask your physician why a given drug is part of the plan and what the evidence behind it is.
Side effects and when to call the clinic
Most side effects come from the hormones and the injections. Commonly reported effects include:
- Bloating, breast tenderness, and fatigue
- Mood swings or irritability
- Headaches
- Soreness, bruising, or small lumps at injection sites
- Hot flashes while on ovulation suppression
These are usually manageable. Certain symptoms need prompt attention from the clinic's nurse or physician: severe abdominal pain, heavy bleeding, shortness of breath, chest pain, one swollen and painful leg, a severe or sudden headache, or signs of an allergic reaction such as hives or swelling of the face. In an emergency, the surrogate should seek urgent care and tell the treating team that she is on hormone therapy.
A missed dose is another situation where the surrogate should call the clinic rather than guess. Timing in a medicated cycle is tight, and the nurse can say whether to take the dose late, skip it, or adjust the schedule.
Ovarian hyperstimulation syndrome, a risk with fertility drugs that stimulate the ovaries, is a concern mostly for egg providers, not for surrogates on a replacement cycle. It is described in FDA prescribing information for gonadotropins. Intended parents using an egg provider should discuss it with their own fertility specialist.
What intended parents should ask the clinic
You are not the one taking the drugs, but you are responsible for the process and the surrogate's wellbeing. A good set of questions to put to your reproductive endocrinologist:
- What is the full medication protocol for the surrogate, including doses, routes, and start dates?
- Who trains the surrogate to inject, and is a nurse available for questions at any hour?
- How is the lining monitored, and what happens if it does not respond?
- How many embryos will be transferred? Single embryo transfer lowers the risk of multiples. The ASRM committee opinion on multiple gestation explains the reasoning behind limiting embryos transferred.
- When does medication end after a positive result, and who makes that call?
- Who covers the medication costs and any side-effect-related care, and where is that written in the agreement?
Put the answers in writing and keep them with your records. If anything is unclear, ask again, because clear answers are part of ethical care.
Prenatal care during surrogacy
Once a heartbeat is confirmed and the clinic releases the surrogate from fertility care, she moves to an obstetric provider for routine prenatal care. The care itself is the same as for any pregnancy: scheduled visits, blood work, ultrasounds, screening tests, and a delivery plan. Because the pregnancy came from IVF, her team may monitor it somewhat more closely. ACOG notes perinatal risks associated with assisted reproductive technology, which is one reason obstetric follow-up matters.
Three practical points for intended parents:
- Information flow. Agree in advance how updates are shared and whether you attend appointments, in person or by video. This belongs in the surrogacy agreement, not in improvised conversations.
- Decisions belong to the surrogate. She consents to her own medical care. Respect for her autonomy is part of ethical surrogacy practice worldwide.
- Medication safety. Any new prescription or over-the-counter product should be cleared with her obstetric provider, who knows her history and the pregnancy's progress.
Plan for birth, too. Hospital policies, who may be present, and how the baby is handed to the parents are best settled long before labor. Our step-by-step guide to surrogacy in Colombia shows where prenatal care and delivery sit in the full timeline.
Our perspective on medication in surrogacy
We see medication as the most visible part of what a surrogate gives. For weeks, she follows a strict schedule that affects her daily life, and intended parents should recognize that effort as the real beginning of the relationship. In our experience, families who understand the medication plan tend to ask better questions and treat the surrogate with more empathy.
Transparency is what we emphasize. Each intended parent, whether a gay or lesbian couple, a transgender couple, a heterosexual couple, or a single parent, should know which drugs are used, why, and what the risks are. The medical decisions stay with the physicians. Our role is to coordinate the legal and medical arrangements around those decisions so no one is left guessing.
Colombia's setting matters as well. Surrogacy there operates under legal protections intended to keep the process safe and altruistic, and our team includes legal and medical professionals, some with personal surrogacy experience. Our clinic is highly rated, and we have supported over 60 live births. We believe that a well-informed surrogate and well-informed parents make for a calmer pregnancy, and that is the standard we hold ourselves to.
— Florent Letronne, PhD
Working with a team that explains each step
If you are comparing surrogacy options, ask any agency how openly it discusses medical protocols before you sign. At Colombia Surrogacy Partners, we guide intended parents through matching, legal advisory, medical oversight, and support from the first consultation through the birth. We work with gay couples, lesbian couples, transgender couples, heterosexual couples, singles, and international intended parents. To talk through your situation, start at our main surrogacy page. For cost questions, see our page on affording surrogacy and our comparison of international and US surrogacy.
FAQ
How long does a surrogate take medication before the transfer?
The lead-up commonly runs several weeks, from the first birth control pills through estrogen and progesterone, though the exact length depends on the clinic's protocol. Medication then continues after the transfer, often into the first trimester, until the physician says it can stop.
Are surrogacy medications safe for the surrogate?
These are established drugs used in routine IVF and frozen embryo transfer cycles, and they are prescribed and monitored by a physician. They still carry side effects and risks, which vary by person. A surrogate should be screened beforehand and should report severe or unusual symptoms to the clinic immediately.
Do intended parents take any medication?
Not for the surrogate's cycle. If an intended mother provides eggs, she follows her own stimulation protocol with her fertility specialist. Egg donors and intended fathers have separate medical steps, discussed with the clinic.
Who pays for the surrogate's medications?
In most arrangements, intended parents cover the medications and related medical costs, and the agreement should say so in detail. Ask your agency for a written breakdown before you commit, so there are no surprises.
Does prenatal care differ in a surrogate pregnancy?
The basic schedule matches any pregnancy, with a standard obstetric team. Because conception occurred through IVF, the provider may watch the pregnancy more closely. Communication about visits, test results, and birth plans between the surrogate and the parents should be set out in advance.
Sources
- ACOG: Family Building Through Gestational Surrogacy
- ACOG: Perinatal Risks Associated With Assisted Reproductive Technology
- ASRM: Multiple gestation associated with infertility therapy, a committee opinion (2022)
- Acacio Fertility: Preparing Embryo Recipients, Egg Donation and Gestational Surrogacy
- FDA: Progesterone Injection USP in sesame oil, prescribing information
- FDA: Gonal-f RFF prescribing information