Also known as Follicle-stimulating hormone · Follitropin alfa · Gonal-f · Follistim · Puregon
A heterodimeric glycoprotein gonadotropin that drives follicle growth and spermatogenesis — the workhorse of IVF stimulation, and a sister molecule to HCG and LH.
Follicle-stimulating hormone is one of the three pituitary glycoprotein gonadotropins, and like its siblings LH and HCG it is built from a shared alpha subunit paired with a hormone-specific beta subunit, heavily glycosylated. FSH is the signal that recruits and grows ovarian follicles in women and supports sperm production in men, which makes recombinant FSH (follitropin) the central tool of assisted reproduction — the drug that drives controlled ovarian stimulation in IVF.
FSH completes the gonadotropin picture alongside HCG and LH in this catalog: the same alpha subunit, a distinct beta subunit, and obligatory glycosylation that makes it a true glycoprotein hormone rather than a simple peptide. Its job is the front half of the reproductive cycle — recruiting and maturing ovarian follicles — where LH and the LH-mimicking HCG handle the ovulatory trigger that follows.
Therapeutically, recombinant FSH (follitropin alfa, Gonal-f; follitropin beta, Follistim) is produced in mammalian cells so its glycosylation is human-like, and it is the backbone of controlled ovarian stimulation in IVF — driving the development of multiple follicles in a cycle — as well as treatment for anovulation and certain male infertility. Older urine-derived gonadotropin products (menotropins) supplied FSH and LH activity together; recombinant versions allow precise, consistent dosing.
FSH is less surrounded by pop-culture drama than oxytocin or HCG, but it carries the same molecular lesson: glycoprotein hormones are assembled, glycosylated biologics whose sugar chains are part of the drug, which is why they are grown in cells and characterized by glycan and bioassay analytics rather than a simple purity figure.
Binds the FSH receptor on ovarian granulosa cells (driving follicle maturation and estrogen production) and on testicular Sertoli cells (supporting spermatogenesis). Its glycosylation governs its circulating half-life and activity.
Behind every vial of FSH (Follitropin) is the same exacting pipeline every research peptide runs — but the chemistry plays out differently for this molecule. Here is how FSH (Follitropin), specifically, is brought into being.
On paper, FSH (Follitropin) weighs in at roughly 30,000 daltons. Before a single bond is made, the target sequence, salt form, and purity threshold are written down as the contract the finished material must meet.
FSH (Follitropin) is assembled by solid-phase peptide synthesis — the chain grows one protected residue at a time on resin, and what you fail to build cleanly here you pay to remove later.
The crude mixture — FSH (Follitropin) plus its deletions and side products — is then separated on preparative HPLC, and where the cut is taken decides the difference between a genuinely pure peptide and a barely-passable one.
A real batch of FSH (Follitropin) proves itself: identity confirmed by mass spectrometry against its ~30,000 Da, purity read directly off an analytical HPLC trace, water and counterion content measured. That batch-specific certificate of analysis is the only honest way to know what is actually in a vial of FSH (Follitropin) — and a short, cold, accountable chain of custody is how that purity survives the trip to your bench.
Recombinant follitropin is produced in mammalian (CHO) cells so its essential glycosylation is human-like; its ~30 kDa mass is approximate and varies with glycosylation, so it has no single molecular formula. Characterization is glycoprotein-grade — subunit identity, glycan/isoform profiling, and bioassay potency — well beyond an HPLC purity number.
Don't judge a vial by its cake. A fluffy, good-looking lyophilized powder reflects bulking agents and freeze-drying parameters — not purity. Insist on a batch-specific certificate of analysis.
Recent clinical trials and publications mentioning Follicle-stimulating hormone, pulled automatically from ClinicalTrials.gov and PubMed and refreshed daily. Listings are unfiltered search results, not curated endorsements.
Follicle-stimulating hormone drives the growth of ovarian follicles in women and supports sperm production in men. As recombinant follitropin it is the main drug used to stimulate the ovaries in IVF.
They are all glycoprotein gonadotropins sharing the same alpha subunit; their unique beta subunits give them different jobs. FSH grows follicles, while LH and the LH-mimicking HCG trigger ovulation.
It is a two-subunit, heavily glycosylated protein whose sugar chains are essential to its activity and half-life. It is made in mammalian cells so glycosylation is human-like — not by peptide synthesis.
No — this is a research and educational reference, not dosing guidance.