A tier · strong
A long-established FDA-approved gonadotropin with registration-grade randomized ART trial data and quantified pregnancy, OHSS and multiple-gestation rates on its label, held below S because it is a bioactivity-standardised urinary extract rather than a defined molecular entity.
hmg
Menotropins are a purified urinary gonadotropin preparation carrying both FSH and LH activity, FDA-approved for developing multiple follicles as part of assisted reproductive technology. The registration trials report a clinical pregnancy rate around one in four alongside a clearly quantified ovarian hyperstimulation and multiple-birth burden.
the explanation
HMG is a fertility injection made from purified hormones collected from the urine of post-menopausal women, containing both of the signals the ovaries need to grow eggs. It works well enough to be an approved IVF medicine, but it also raises the odds of overstimulated ovaries and of twins or triplets.
regulatory status
FDA-approved prescription biologic extract
Menopur (menotropins for injection, USP; NDA 021663) is approved for the development of multiple follicles and pregnancy in ovulatory women as part of an Assisted Reproductive Technology cycle. The label describes the product as extracted from the urine of postmenopausal women and further purified. It is prescription-only and administered under specialist supervision; individual gonadotropin components fall under WADA S2 controls in sport contexts.
how it works · proposed mechanism
Menotropins supply exogenous FSH and LH-like activity directly to the gonads, bypassing pituitary regulation.
FSH receptor stimulation
The FSH component acts on granulosa-cell FSH receptors to recruit and grow multiple ovarian follicles simultaneously. This overrides the single-dominant-follicle selection that normally occurs each cycle.
LH-like theca support
The LH activity, largely from co-purified hCG, stimulates theca cells to supply androgen substrate for granulosa-cell aromatisation to oestradiol. This two-cell, two-gonadotropin support is the stated rationale for a combined rather than FSH-only preparation.
Potency defined by bioassay
Because the preparation is a urinary extract, each vial is standardised to international units of FSH and LH activity rather than to milligrams of protein. Batch equivalence therefore rests on bioassay, not on mass spectrometry.
what’s reported
evidence shape
5 sourcesThe composition of the cited literature by study type. This describes the shape of the evidence, not its quality — and it does not by itself set the grade.
⚠ the catch
The efficacy and the harm come from the same mechanism: driving many follicles at once produces both the pregnancy rate and a 7.2% OHSS incidence with over a third of resulting pregnancies being multiple. Because potency is defined by bioassay rather than mass, batch-to-batch consistency depends entirely on the manufacturer's standardisation.
key published findings
- Human trial: in the registration IVF/ICSI study 373 patients were randomized to the menotropins arm, yielding a 26% clinical pregnancy rate (98 patients) and a 23% continuing pregnancy rate (87 patients).
- Human trial (safety): OHSS occurred in 7.2% of the 373 treated women, and multiple pregnancy diagnosed by ultrasound occurred in 35.3% (n=30) of 85 total pregnancies.
- Human trial (adverse events, incidence >=2%): abdominal pain 6.7%, headache 6.2%, OHSS 6.2%, injection-site pain and reaction 3.9%, abdominal cramps 3.0%, abdomen enlarged 2.3%, injection-site inflammation 2.3%; thrombophlebitis was reported in under 1% of subjects.
- Human pharmacokinetics: FSH elimination half-lives in the multiple-dose phase were similar at 11-13 hours for both subcutaneous and intramuscular routes.
- Composition finding: the FDA label specifies each vial contains 75 IU of FSH activity and 75 IU of LH activity, extracted from the urine of postmenopausal women and further purified.
limitations of the evidence
- Potency is standardised by bioactivity rather than by defined molecular mass, so the product is an extract whose consistency cannot be verified by simple chemical assay.
- Approved efficacy data are specific to ART cycles in ovulatory women under specialist monitoring, and do not transfer to unmonitored use in other populations.
- The label notes that benign and malignant ovarian neoplasms have been reported infrequently after multiple-drug controlled ovarian stimulation, but a causal relationship is not established, leaving long-term oncological risk unresolved.
documented safety signals
- OHSS is the principal serious risk: the label states OHSS occurs after gonadotropin treatment has been discontinued and can develop rapidly, reaching maximum about seven to ten days following treatment. Severe forms involve fluid accumulation, electrolyte imbalance, pulmonary distress and thromboembolic events.
- Thromboembolic events have been reported both in association with and separate from OHSS in patients receiving gonadotropins, and have been fatal in rare cases.
- Multiple gestation occurred in 35.3% of pregnancies in the registration data, carrying the associated maternal and neonatal risks of multi-fetal pregnancy.
- Ovarian torsion has been reported after gonadotropin treatment; the label notes early diagnosis and immediate detorsion can limit ovarian damage from reduced blood flow.
- Benign and malignant ovarian neoplasms have been reported infrequently in women receiving multiple-drug controlled ovarian stimulation, with causality not established.
- As a urine-derived biological extract, product quality depends entirely on manufacturer purification; unregulated or grey-market material carries uncharacterised contamination and immunogenicity risk that no published trial addresses.
- Because menotropins carry LH/hCG-like bioactivity, use in male athletes engages the same WADA S2 testosterone-stimulating-peptide prohibition that applies to chorionic gonadotrophin.
identity
| full name | Human Menopausal Gonadotropin (Menotropins) |
| category | Hormonal |
| modality | protein hormone |
| cas | 61489-71-2 |
| half-life | FSH elimination half-life approximately 11-13 hours in the multiple-dose phase, similar for subcutaneous and intramuscular routes (Menopur FDA label). |
| sequence | Not a single defined sequence. Menotropins are a purified mixture of urinary glycoprotein gonadotropins standardised by bioactivity, typically 75 IU FSH activity and 75 IU LH activity per vial, with the LH activity supplied largely by co-purified hCG. |
laboratory handling
| storage | Store the lyophilised powder refrigerated or at room temperature, 3-25 C (37-77 F), protected from light. Use immediately after reconstitution and discard unused material. |
| solubility | Lyophilised powder reconstituted in sterile sodium chloride diluent; the glycoprotein components are freely water-soluble. |
| co-studied with | Published ART protocols pair menotropins with an hCG-type trigger and with GnRH agonists or antagonists for pituitary suppression. This index does not describe regimens; the relevant published observation is that combined gonadotropin stimulation is precisely the context in which the label's 7.2% OHSS and 35.3% multiple-pregnancy figures were measured. |
Handling information describes laboratory practice for a research reagent. It is not a preparation guide for use in humans.
the receipts
5 citedU.S. Food and Drug Administration · 2014 · official
DailyMed, U.S. National Library of Medicine · 2024 · official
U.S. Food and Drug Administration · 2004 · official
ChemicalBook · 2024 · official
Drugs.com / American Society of Health-System Pharmacists · 2024 · review
others in Hormonal