What is Menopur?
Menopur, a brand name for menotropins, is a prescription fertility medication containing both follicle-stimulating hormone (FSH) and luteinizing hormone (LH) activity. It is classified as a human menopausal gonadotropin (hMG) and is purified from the urine of postmenopausal women. This combination of both FSH and LH activity differentiates it from fertility drugs containing only FSH. While the body naturally produces these hormones, Menopur is prescribed when there is insufficient natural hormone production or when multiple eggs are needed for assisted reproductive technologies (ART), such as in vitro fertilization (IVF).
The Mechanism: How Menopur Affects the Body
Administered via subcutaneous injection, Menopur influences the reproductive system by mimicking natural gonadotropins to stimulate and control egg growth and maturation.
Ovarian Stimulation for IVF
In women undergoing IVF, Menopur aims for controlled ovarian stimulation. Its combined FSH and LH activity:
- Stimulates Follicular Growth: The FSH stimulates the ovaries to develop multiple follicles, increasing the number of eggs for retrieval.
- Promotes Egg Maturation: The LH aids in the final maturation of eggs within follicles, preparing them for ovulation or retrieval.
- Supports the Endometrium: LH activity may potentially improve endometrial blood flow, possibly enhancing embryo implantation chances.
Potential Effects in Men (Off-label Use)
While primarily for female infertility, Menopur is sometimes used off-label for men with hypogonadotropic hypogonadism to stimulate sperm production. The FSH supports sperm development, and the LH stimulates testosterone production, typically in conjunction with hCG.
Menopur vs. Other Fertility Medications
Comparing Menopur to other fertility drugs, like recombinant FSH (rFSH) products such as Gonal-F, is important due to their different compositions.
| Feature | Menopur (hMG) | Recombinant FSH (e.g., Gonal-F) |
|---|---|---|
| Composition | Contains both FSH and LH activity | Contains only FSH |
| Source | Derived from the urine of postmenopausal women | Lab-made (synthetic) |
| Primary Function | Stimulates follicular growth and aids egg maturation via combined FSH/LH action | Primarily stimulates follicular growth via FSH action |
| Potential Benefit | LH activity may offer advantages like improved embryo quality or pregnancy rates in some IVF protocols | Purer FSH stimulation, potentially a smoother injection experience |
| Use Case | Often used in IVF for controlled ovarian stimulation | Often used in IVF, sometimes alongside Menopur for a combined effect |
Potential Side Effects and Risks
Menopur, like all medications, has potential side effects, ranging from common symptoms to serious risks.
Common Side Effects:
- Headache
- Abdominal pain or bloating
- Nausea and/or vomiting
- Injection site reactions (pain, swelling, redness)
- Breast tenderness
- Dizziness or fatigue
Serious Side Effects and Risks:
- Ovarian Hyperstimulation Syndrome (OHSS): A serious condition from overstimulated ovaries, causing swelling and fluid buildup. Severe cases need hospitalization. Monitoring by a doctor helps manage this risk.
- Blood Clots: Rare but possible increased risk, especially for those predisposed. Symptoms like chest pain or shortness of breath require immediate medical attention.
- Multiple Pregnancies: Increased egg stimulation significantly raises the risk of multiple births (twins, triplets), which have higher risks for mother and babies.
- Ectopic Pregnancy: Higher risk in all ART procedures, especially with fallopian tube issues.
Conclusion
What does Menopur do to the body? It provides essential FSH and LH activity to significantly impact fertility, particularly in IVF and other ARTs. It promotes the development and maturation of multiple eggs, offering hope for many. However, its use requires close medical supervision due to risks like OHSS and multiple pregnancies. Patients must communicate openly with healthcare providers who monitor their response and adjust dosing for optimal results and safety. Menopur is a complex but crucial part of the fertility journey for many. For more information, refer to the FDA patient labeling at accessdata.fda.gov.
