What is HMG?
After menopause, the ovaries stop responding to the pituitary, so the pituitary releases large amounts of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), much of which passes into the urine. HMG is made by collecting and purifying these hormones, and its generic name is menotropins. Like HCG, FSH and LH are glycoprotein hormones, large proteins with sugar groups attached, rather than short peptides.
HMG has been used in fertility medicine since the early 1960s and was one of the first effective fertility drugs. Modern highly purified versions, such as Menopur, are still widely used in IVF. In some of these products, part of the LH-like activity comes from HCG rather than LH itself. Recombinant FSH made in cell culture has since become an alternative, and the two are often compared.
How does HMG work?
FSH and LH have different jobs. In women, FSH drives the growth of ovarian follicles, the fluid-filled sacs that hold developing eggs, while LH activity helps those follicles make estrogen and mature. In men, FSH acts on Sertoli cells in the testes, which support sperm development, and LH acts on Leydig cells to make testosterone. Sperm production needs both. HMG supplies both signals directly to the ovaries or testes, which is why it is used when the body's own FSH and LH are too low.
What has HMG research looked at?
- IVF and ovarian stimulation
- HMG is one of the standard medicines used to stimulate the ovaries to develop multiple eggs in IVF. Trials comparing it with recombinant FSH have generally found broadly similar pregnancy and live birth rates.
- Ovulation induction
- In women whose pituitary makes too little FSH and LH, HMG has long been used to induce ovulation, since FSH-only products may not supply enough LH activity.
- Male hypogonadism
- In men with low FSH and LH from pituitary or brain causes, treatment with HCG combined with HMG or FSH can start sperm production, though it often takes many months.
- After testosterone or steroid use
- Small studies and case series have described HCG and HMG or FSH being used to help restore sperm production after testosterone or anabolic steroid use, but controlled trials are limited.
HMG has a long clinical record in established fertility care, both in women and in men with low pituitary hormones. Its use outside fertility treatment, such as for general hormone optimization in men with normal hormone levels, has little direct research behind it.
HMG vs HCG
HCG acts mainly like LH, so it is best at prompting the testes to make testosterone or triggering final egg maturation. HMG adds FSH, the main signal for follicle growth in women and for sperm development in men. In fertility care the two are often used in sequence or together, with HMG supporting follicle growth or sperm production and HCG supplying LH activity. Neither works when the ovaries or testes themselves have failed, because both depend on those organs responding.
HMG side effects and cautions
In women, the main serious risk is ovarian hyperstimulation syndrome, where the ovaries over-respond and fluid shifts in the body. HMG also raises the chance of twins or higher multiples. Other reported effects include headache, bloating, abdominal discomfort, nausea and reactions where it is given. In men, breast tenderness or growth and acne can occur. Treatment is normally monitored closely with blood tests and, in women, ultrasound. Anyone with health questions about it should talk to a qualified clinician.
- Ovarian hyperstimulation
- This can range from mild bloating to a serious condition with fluid buildup and blood clots, and is the main reason for close monitoring.
- Multiple pregnancy
- Stimulating several follicles raises the chance of twins or more, which carries higher risks in pregnancy.
- Hormone-sensitive conditions
- Hormone-sensitive cancers, pituitary tumors and untreated thyroid or adrenal problems are standard cautions.
- Ovarian or testicular failure
- HMG cannot help when the ovaries or testes no longer respond, and it is not used during pregnancy.
Further reading
This page summarizes the research in plain words. To read the studies yourself:
- Published studies on HMG PubMed, US National Library of Medicine
- Registered human trials of HMG ClinicalTrials.gov
