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 Concern
 Treatment
Pregnancy
Experiences
Treatment
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Second Step
Gonadotropin Treatment
If clomiphene does not work, the next stage of
treatment is to start administering gonadotropins. Where clomiphene
acts to stimulate the release of gonadotropin-releasing hormone,
gonadotropins act directly on the ovary, promoting follicular
development.
The gonadotropin hormones used in infertility treatment are now
made in three ways:
- Urinary: Fertility hormones
were only extracted and purified from the urine of postmenopausal
women.
- Recombinant: The production
of fertility hormones using deoxyribonucleic acid (DNA). Find out more!
- Recombinant using Filled by Mass
technology: A more accurate and precise technique, using
size-exclusion, high-pressure liquid chromatography. Tell me more!
See Personalised Treatments for more detail
on these three techniques.
Gonadotropins
The two main gonadotropins are
follicle-stimulating hormone (FSH) and luteinising hormone (LH).
These are considered to be gonadotropins because they exert their
effects primarily upon the ovaries and testes (which are known as
gonads).
The suffix -trophin or -tropin means ‘growth promoting’ because
not only do these hormones stimulate the release of the gonadal
hormones, they are also responsible for the growth and development
of the gonads. In the absence of the gonadotropins, the gonads
atrophy and if they are absent during childhood, the gonads do not
develop properly.
In females, FSH and LH exert distinct but complementary actions on
the growth and development of ovarian follicles, and the synthesis
and secretion of key ovarian hormones such as oestrogens and
progesterone. FSH acts to drive follicular development, while LH is
the primary hormone involved in producing and initiating the luteal
phase. Decreases or imbalances in the levels of FSH and LH can lead
to anovulation (cessation of ovulation) and infertility.
Conversely, after the menopause or in women who are unable to
produce oestrogens, FSH may rise to very high levels because of the
absence of oestrogen's negative feedback to the hypothalamus.
In males, the action of FSH is primarily on seminiferous tubule
maturation in the testes. The target cells of the hormone are the
Sertoli cells. In the presence of a high intratesticular androgen
level (which arises as a result of the action of LH in the testes,
which stimulates the Leydig cells to develop and secrete
testosterone), FSH induces spermatogenesis.
The specific functions of the
gonadotropins are summarised in the table below.
| Hormone | Function in females | | Follicle-stimulating hormone | Key hormone involved in the
development and maturation of the ovarian follicle to the point of
ovulation
Stimulates follicular cells to secrete oestrogens | | Luteinising hormone | Essential for producing ovulation
and formation of the corpus luteum, which secretes hormones needed
to support early pregnancy
Circulating levels appear to play a role in conjunction with FSH in
development of follicle |
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There are five types of hormone, each with a
specific role in female fertility: 
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