Pregnyl Dose and Timing for Fertility Treatment
For ovulation induction in assisted reproductive technology, administer 5,000-10,000 IU hCG intramuscularly or subcutaneously when at least 3 follicles reach ≥17-18 mm diameter, followed by oocyte retrieval or insemination 24-40 hours later. 1, 2
Dosing by Clinical Indication
IVF/ICSI Cycles
- Standard dose: 5,000-10,000 IU administered when ≥3 follicles reach >17 mm with appropriately rising estradiol 2
- Both intramuscular and subcutaneous routes are bioequivalent and equally effective 3
- Oocyte retrieval typically occurs approximately 40 hours after hCG administration 1
- The 10,000 IU dose produces higher peak serum levels (339 IU/L subcutaneous vs 307 IU/L intramuscular) compared to 5,000 IU (156 IU/L), though both are effective 3
IUI with Ovarian Stimulation
- Timing window: 24-40 hours post-hCG for single insemination without compromising pregnancy rates 1, 4
- Trigger when dominant follicle reaches approximately 18 mm mean diameter 1
- This flexible timing window allows practical scheduling while maintaining efficacy 4
Male Hypogonadotropic Hypogonadism
- Initial therapy: 500-2,500 IU administered 2-3 times weekly per Endocrine Society recommendations 2
- FDA-approved regimens include:
- Monitor serum testosterone response before adding FSH analogues 4, 2
Route of Administration Considerations
Subcutaneous and intramuscular routes are bioequivalent with respect to extent of absorption (AUC), making subcutaneous administration a valid alternative that patients can self-administer 3. The elimination half-life is 32-33 hours regardless of route 3. Subcutaneous administration may achieve slightly higher peak concentrations (339 vs 307 IU/L for 10,000 IU dose) but this difference is not clinically significant 3.
Critical Safety Parameters
Withhold hCG administration when:
2 dominant follicles >15 mm are present, OR
5 follicles >10 mm are present 2
This prevents high-order multiple gestations and severe ovarian hyperstimulation syndrome (OHSS) 2. The risk of OHSS is particularly elevated in high-responder patients, where GnRH agonist triggers (triptorelin 0.2 mg subcutaneous) may be considered as an alternative 6.
Pharmacokinetic Profile
- Peak serum levels: Achieved at approximately 20 hours post-injection 3
- Elimination half-life: 32-33 hours across all dosing regimens 3
- Duration of detectability: 7 days after 10,000 IU (IM or SC), but <7 days after 5,000 IU IM 7
- Dose proportionality: 5,000 IU and 10,000 IU doses are dose-proportional 3
Clinical Outcomes by Dose
The 5,000 IU dose is generally sufficient for triggering ovulation, while higher doses (10,000 IU) may provide better luteal phase support due to prolonged detectability 7. Studies show that 10,000 IU produces significantly different intraovarian artery blood flow and follicular development compared to 5,000 IU, with higher progesterone levels and more total oocytes retrieved 8. However, mature oocyte rates and fertilization rates remain comparable between doses 8.
Practical Reconstitution
Per FDA labeling, withdraw sterile air from lyophilized vial and inject into diluent vial, then remove 1-10 mL diluent and add to lyophilized vial with gentle agitation until completely dissolved 5. Use completely after reconstitution; reconstituted solution is stable for 60 days when refrigerated 5.
Common Pitfalls to Avoid
- Never prescribe testosterone monotherapy to men interested in current or future fertility, as it suppresses spermatogenesis 2
- Do not use hCG in males currently on exogenous testosterone therapy, as it may suppress gonadotropin secretion and negate hCG benefits 2
- Avoid rigid adherence to narrow timing windows for IUI—the 24-40 hour window provides flexibility without compromising outcomes 1
- In natural IUI cycles without ovarian stimulation, perform insemination 1 day after LH rise rather than using hCG trigger 1