IVF Medication Guide: Injections, Progesterone, and HCG Explained
IVF Medication Guide: Injections, Progesterone, and HCG Explained Key Takeaways: IVF treatment involves multiple medications, but each serves a precise purpose — from suppressing the pituitary gland...
IVF Medication Guide: Injections, Progesterone, and HCG Explained
Key Takeaways: IVF treatment involves multiple medications, but each serves a precise purpose — from suppressing the pituitary gland to stimulating follicles, triggering ovulation, and supporting the luteal phase. At AddBaby Fertility Center, our clinical experience shows that patients who understand why each medication is used, how to administer it, and what to expect experience significantly less anxiety and better treatment compliance. This guide walks you through every medication used across a complete IVF cycle.
Quick Reference: IVF Medications by Phase
| Phase | Key Medications | Administration | Core Purpose |
|---|---|---|---|
| Down-regulation (Long Protocol) | GnRH agonists (Decapeptyl, Lupron) | Subcutaneous injection, daily or depot | Suppress pituitary, prevent premature ovulation |
| Ovarian stimulation | rFSH (Gonal-F, Puregon), HMG (Menopur) | Subcutaneous injection, daily | Stimulate synchronous multi-follicle development |
| Antagonist phase | GnRH antagonists (Cetrotide, Orgalutran) | Subcutaneous injection, daily | Block spontaneous LH surge (premature ovulation) |
| Trigger shot | HCG (Ovitrelle) or GnRHa trigger | Subcutaneous/IM, single dose | Trigger final egg maturation |
| Endometrial preparation (FET) | Estradiol valerate (Progynova) ± low-dose aspirin | Oral/patches | Build and optimize uterine lining receptivity |
| Luteal support | Progesterone (vaginal/IM/oral) ± estrogen | Multiple routes | Maintain luteal function, support early pregnancy |
Down-Regulation Phase Medications (Long Protocol)
What Is "Down-Regulation" and Why Is It Needed?
In the Long Protocol, ovarian stimulation is preceded by "down-regulation" — using medications to suppress pituitary secretion of gonadotropins (FSH and LH), bringing the ovaries to a quiescent state. The goal is to prevent follicles from maturing and ovulating spontaneously before stimulation medications can take effect, allowing the physician to synchronously initiate multiple follicles within a precise treatment window.
AddBaby physicians typically begin down-regulation on cycle Day 2 or at a designated point. Ultrasound and blood tests confirm that adequate suppression has been achieved before ovarian stimulation is started.
Commonly Used Down-Regulation Medications
GnRH Agonists are the cornerstone of down-regulation. Paradoxically, their continuous stimulation of pituitary GnRH receptors ultimately causes pituitary desensitization, dramatically reducing FSH and LH secretion.
- Decapeptyl (Triptorelin): Most widely used; available as a daily subcutaneous injection (0.1mg/day) or a monthly depot formulation (3.75mg)
- Leuprolide (Lupron): Extensively used in North America; daily subcutaneous injection
- Buserelin (Superfact): Common in Europe; nasal spray or subcutaneous injection
Common Side Effects During Down-Regulation
Because down-regulation temporarily lowers estrogen levels, approximately 60-70% of patients experience menopausal-type symptoms within 1-2 weeks of starting:
- Hot flashes and night sweats: Most common; usually mild; manageable with breathable clothing and a cool environment
- Mood swings and irritability: Caused by hormonal fluctuation; advance communication with family members helps
- Headaches and sleep disturbances: Typically mild and short-lived
- Vaginal dryness: A direct consequence of declining estrogen
Important: These symptoms are expected responses indicating the medication is working. If symptoms significantly impair daily function, contact your AddBaby physician promptly.
Ovarian Stimulation Phase Medications
The stimulation phase is the central stage of the IVF cycle, typically lasting 8-14 days. Physicians monitor follicle development every 2-3 days via ultrasound (follicle size) and blood tests (estradiol, LH levels), adjusting medication doses dynamically.
Recombinant FSH (Follicle-Stimulating Hormone)
Recombinant FSH (rFSH) is the primary stimulation agent, produced via genetic engineering for high purity and batch consistency.
- Gonal-F (follitropin alfa): The most widely prescribed rFSH; available in a convenient pen injector system
- Puregon (follitropin beta): Equivalent potency to Gonal-F; also available as a pen injector
Typical doses: Based on age, AMH, antral follicle count (AFC), and prior response, starting doses are usually 150-225 IU/day, adjusted upward or downward per monitoring. High-reserve patients may start at 75-100 IU; low-reserve patients may require 300-450 IU.
Human Menopausal Gonadotropin (HMG)
HMG contains both FSH and LH activity in physiological proportions, more closely approximating natural gonadotropin signaling.
- Menopur (menotropin): The classic HMG formulation containing equal FSH and LH activity (75 IU each); subcutaneous injection
- Appropriate for patients with low LH levels, or as a combination therapy with recombinant FSH
The role of LH in late follicular development is increasingly recognized — appropriate LH concentrations support egg quality, particularly for low-reserve and older patients.
GnRH Antagonists (Antagonist Protocol)
In the Antagonist (Short) Protocol, no prior down-regulation is used. GnRH antagonists are instead added mid-stimulation (typically Days 5-7, when the lead follicle reaches 12-14mm) to block a spontaneous LH surge:
- Cetrotide (cetrorelix): 0.25mg daily subcutaneous injection, or 3mg single-dose formulation
- Orgalutran/Ganirelix: 0.25mg daily subcutaneous injection
Advantages of the antagonist protocol include a shorter total medication course (approximately 2 weeks, no prior down-regulation), lower OHSS risk, and particular suitability for PCOS and high-reserve patients. AddBaby recommends the protocol type most appropriate for each patient's ovarian reserve and history.
Common Side Effects During Stimulation
- Bloating and pelvic discomfort: As follicles multiply and ovaries enlarge; typically mild to moderate
- Mood swings: Related to rapidly rising estrogen levels
- Breast tenderness: Secondary to elevated estrogen
- Mild nausea: Uncommon; usually minor
Critical warning: Ovarian Hyperstimulation Syndrome (OHSS) — manifesting as severe abdominal swelling, difficulty breathing, and oliguria — is the most serious stimulation complication. AddBaby minimizes OHSS risk through close monitoring, individualized dose adjustments, and timely interventions (including "freeze-all" strategies and antagonist protocols). For detailed information on OHSS, see our Complete OHSS Guide.
Trigger Shot and Transfer-Related Medications
HCG Trigger — Initiating Final Egg Maturation
When the lead follicle reaches 18-20mm in diameter and at least three follicles are ≥17mm, the physician instructs the patient to administer the trigger shot, inducing the final maturation of eggs (second meiotic division).
- Recombinant HCG (Ovitrelle, choriogonadotropin alfa): 250µg subcutaneous injection; the most commonly used option; egg retrieval occurs precisely 36-38 hours after injection
- Urinary HCG (Pregnyl, Choragon): 5,000-10,000 IU intramuscular injection; equally effective
The timing precision of the trigger is critical — premature injection results in immature eggs, while delayed injection risks spontaneous ovulation. Always follow the exact injection time specified by your AddBaby team, even if it falls in the middle of the night.
GnRHa Trigger — Reducing OHSS Risk
For patients at high risk for OHSS (PCOS, high AMH, numerous developing follicles), a GnRH agonist trigger (e.g., Decapeptyl 0.2mg subcutaneously) can substitute for HCG. The GnRHa trigger elicits an endogenous LH surge with a shorter duration than HCG, substantially lowering OHSS risk. This strategy is typically paired with a "freeze-all" approach (no fresh transfer).
Endometrial Preparation (Frozen Embryo Transfer Cycle)
Before frozen embryo transfer, the uterine lining must be optimally prepared:
- Estradiol valerate (Progynova): Oral or patch formulation, 2-6mg daily for 10-14 days
- Low-dose aspirin (75-100mg/day): Added in some protocols to improve uterine blood flow (evidence remains debated; practice varies by center)
Once ultrasound confirms endometrial thickness ≥8mm with a trilaminar pattern, progesterone supplementation begins. Embryo transfer follows 4-6 days after progesterone initiation.
Luteal Phase Support Medications
After egg retrieval or embryo transfer, corpus luteum function may be insufficient (particularly following ovarian stimulation), making external progesterone supplementation necessary to support early pregnancy until the placenta establishes autonomous hormone secretion — typically by weeks 8-10 of pregnancy.
Progesterone Delivery Routes
Vaginal Suppositories/Gel (Most Common):
- Crinone 8% gel: 1-2 vaginal applications daily; high local bioavailability; fewer systemic side effects
- Utrogestan (micronized natural progesterone): Vaginal insertion or oral, 100-200mg per dose, 2-3 times daily
- Advantages: Stable absorption without injections; disadvantages: possible increased vaginal discharge
Intramuscular (IM) Progesterone:
- Oil-based progesterone injection, 50-100mg IM daily
- Advantages: Measurable, stable blood levels; disadvantages: injection site soreness and induration affecting quality of life
Oral Progesterone:
- Lower bioavailability due to first-pass metabolism; typically used as adjunct rather than primary route
AddBaby generally recommends a vaginal-primary strategy with IM supplementation for specific indications, balancing efficacy and patient comfort.
How Long Does Progesterone Continue?
- Continue after a positive beta-hCG test (hCG >25 mIU/mL)
- Weeks 8-10 of pregnancy: After the placenta begins producing adequate progesterone independently, doses are gradually tapered
- Never discontinue progesterone independently — dose reduction must be guided by your physician following ultrasound confirmation of fetal cardiac activity
Estrogen Supplementation in Frozen Embryo Transfer Cycles
In hormone replacement frozen embryo transfer cycles, estrogen supplementation continues:
- Maintained after transfer until weeks 8-10 of pregnancy
- Typically combined with progesterone supplementation
Common Luteal Phase Questions
- Breast tenderness, drowsiness, mood changes from vaginal progesterone: Expected pharmacological effects
- Self-reducing doses due to side effect concerns: Strictly prohibited — may cause luteal insufficiency and increase miscarriage risk
- Injection site induration: Warm compresses and rotating injection sites provide relief
Frequently Asked Questions (FAQ)
Q1: Do I have to inject myself with the stimulation medications?
Not necessarily. Subcutaneous injection technique is relatively simple, and AddBaby nurses provide dedicated training to patients and family members before the first injection. Most patients inject confidently and independently by the second or third time. If self-injection is genuinely impractical, daily clinic visits for nurse-assisted injections are available, or a trained family member can administer the shots. The critical priority is accurate injection timing.
Q2: What if I miss a dose of my stimulation medication?
Contact your AddBaby physician or nursing hotline immediately — do not supplement or skip doses on your own judgment. The precision of stimulation medication timing directly affects follicle development rhythm. Your physician will assess the situation and provide optimal guidance. If the delay is under 2-3 hours, a supplemental injection typically causes minimal disruption; longer delays require ultrasound assessment.
Q3: Will these medications affect my child's health?
Decades of follow-up studies — some spanning 30+ years — consistently demonstrate no significant adverse health effects on offspring from IVF medications, including stimulation drugs and progesterone. Children born through IVF show no statistically significant differences from naturally conceived children in cognitive development, physical health, or congenital anomaly rates. Patients with specific concerns are encouraged to discuss them thoroughly with their AddBaby physician during consultation.
Q4: Is it safe to take these medications during menstruation?
IVF medications are typically initiated at specific points in the menstrual cycle, timed according to reproductive physiology, with well-established safety profiles. Your physician determines the precise start date (Day 1, 2, or 3 of your cycle) based on your test results and protocol.
Q5: Can I obtain these medications in China before traveling?
Some medications (such as Gonal-F and certain recombinant FSH products) are available through Chinese distribution channels, but not all brands and formulations are consistently accessible. AddBaby will clarify — once your treatment protocol is finalized — which medications you should source independently in China, which we will provide or assist in procuring, and will supply a detailed medication management guide to eliminate confusion. For a complete guide to preparing for overseas IVF treatment, see our Overseas IVF Preparation Complete Guide.
Conclusion
The IVF medication protocol appears complex, but every drug has a clear therapeutic rationale:
- Down-regulation agents (GnRH agonists) — Quiet the pituitary, prevent premature ovulation
- Stimulation agents (FSH/HMG) — Synchronously activate multiple follicles, maximize egg yield
- Antagonists — Apply the "brakes" mid-stimulation to prevent a spontaneous LH surge
- Trigger shot (HCG/GnRHa) — Precisely trigger egg maturation and time the retrieval
- Estrogens — Prepare an optimal endometrium for frozen embryo transfer
- Progesterone — Support early pregnancy until the placenta takes over
AddBaby Fertility Center provides every patient with a personalized medication schedule and 24-hour nursing support. We believe an informed patient is the most powerful partner in treatment.
If you are planning IVF treatment or have questions about medication protocols, schedule a complimentary AddBaby consultation — our physicians will answer every question in detail.
Interested in understanding the factors that influence IVF success rates? Read our guide on Key Factors Affecting IVF Success Rates.
This article has been reviewed by the AddBaby Reproductive Medicine Group medical team. Last updated: February 2026
