At a glance
Learn about common IVF medication protocols used in PGT cycles in Thailand, including antagonist, agonist, and natural cycle options, and how PGT affects trigger and retrieval timing.
Understanding IVF Medication Protocols for PGT
When planning a PGT (preimplantation genetic testing) cycle in Thailand, the medication protocol is a key part of the process. The goal is to stimulate the ovaries to produce multiple eggs, which are then retrieved and fertilized. Embryos are biopsied for genetic testing before transfer. The medication protocol can vary based on individual factors such as age, ovarian reserve, and medical history. Below we outline common protocols and medications, and how PGT influences timing.
Common IVF Protocols Used in PGT Cycles
Antagonist Protocol
The antagonist protocol is widely used because it is shorter and has a lower risk of ovarian hyperstimulation syndrome (OHSS). It involves daily injections of follicle-stimulating hormone (FSH) such as Gonal-F (follitropin alfa) or Menopur (menotropins) starting around day 2-3 of the menstrual cycle. After about 5-6 days, a GnRH antagonist (e.g., Cetrotide or Orgalutran) is added to prevent premature ovulation. The trigger shot (hCG or GnRH agonist) is given when follicles reach an appropriate size, typically 36 hours before egg retrieval.
Agonist (Long) Protocol
The agonist protocol uses a GnRH agonist (e.g., Lupron or Buserelin) to suppress the pituitary gland before stimulation begins. This is often started in the luteal phase of the previous cycle or early in the cycle. After suppression is confirmed, FSH injections are added. This protocol may be preferred for patients with endometriosis or high ovarian reserve. It is longer and may require more medication.
Natural or Modified Natural Cycle
In a natural cycle, minimal or no medication is used. The patient’s own single egg is monitored and retrieved. A modified natural cycle may use low-dose FSH or a trigger shot to time retrieval. This option is less common for PGT because only one embryo is produced, but it may be suitable for some patients.
Common Medications Used in IVF for PGT
- Gonal-F (follitropin alfa) – recombinant FSH for follicle growth.
- Menopur (menotropins) – human menopausal gonadotropin containing FSH and LH.
- Cetrotide or Orgalutran – GnRH antagonists to prevent premature ovulation.
- Lupron (leuprolide) – GnRH agonist used in agonist protocols or as a trigger.
- hCG (e.g., Pregnyl, Ovidrel) – used as a trigger to mature eggs.
- Progesterone (e.g., Endometrin, Crinone) – used for luteal phase support after retrieval.
Medication names and brands may vary by clinic and country. Your doctor will prescribe a specific regimen based on your profile.
How PGT Affects Timing of Trigger and Retrieval
PGT requires that embryos be biopsied at the blastocyst stage (day 5-6). This does not change the timing of the trigger shot or egg retrieval, which are based on follicle size. However, because PGT involves freezing all embryos (vitrification) and transferring in a subsequent cycle, the fresh transfer is usually not performed. This means that the luteal phase support after retrieval may be minimal or omitted. The trigger shot itself may be a GnRH agonist (e.g., Lupron) instead of hCG to reduce OHSS risk, especially in antagonist protocols.
What to Confirm with Your Clinic
Every patient is unique. Before starting a cycle, you should discuss with your treating clinic:
- Which protocol is recommended for you and why.
- Specific medications, dosages, and injection schedules.
- How PGT results will affect the timing of frozen embryo transfer (FET).
- Any pre-treatment medications (e.g., birth control pills for cycle scheduling).
- Cost of medications and whether they are included in the package.
- Monitoring schedule (blood tests and ultrasounds) during stimulation.
Your clinic will provide a personalized medication calendar. Always follow their instructions exactly.
Travel Considerations for International Patients
If you are traveling to Thailand for IVF with PGT, plan to stay for at least 2-3 weeks for the stimulation and retrieval phase. Medications may need to be shipped or purchased locally. Confirm with your clinic whether you can bring your own medications or if they provide them. Some medications require refrigeration. Discuss storage and travel logistics with your clinic and airline.
For more on the overall process, see our guides on IVF in Thailand and treatment process. International patients can find additional resources on our international patients page.
Frequently asked questions
What is the most common IVF protocol for PGT in Thailand?
The antagonist protocol is commonly used because it is shorter and has a lower risk of OHSS. However, the best protocol depends on individual factors such as age, ovarian reserve, and medical history. Your doctor will recommend a protocol tailored to you.
Do I need to take medication before starting stimulation?
Some protocols use birth control pills or GnRH agonists to schedule the cycle or suppress the ovaries. This is determined by your clinic based on your treatment plan.
How long will I need to stay in Thailand for the medication phase?
The stimulation phase typically lasts 10-14 days, plus a few days for monitoring and the retrieval. Plan for at least 2-3 weeks in Thailand for the egg retrieval cycle. Confirm exact timelines with your clinic.
Can I bring my own IVF medications to Thailand?
It depends on the clinic's policy and Thai customs regulations. Some clinics provide medications, while others allow you to bring them. Check with your clinic and the Thai Food and Drug Administration for import rules.
Does PGT affect the type of trigger shot used?
Yes, in antagonist protocols, a GnRH agonist trigger (e.g., Lupron) is often used instead of hCG to reduce OHSS risk. This does not affect PGT, as eggs are still retrieved and fertilized normally.
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Medical information notice: This article is educational and does not replace individual assessment, diagnosis, genetic counselling or treatment advice from a licensed clinician. Provider services, availability, fees and policies should be verified directly before booking.
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