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P A R T 7
Drugs acting on the reproductive system
to stimulate follicles and ovulation or stimulate the
hypothalamus to increase FSH and LH levels, leading to
ovarian follicular development and maturation of ova.
Given in sequence with human chorionic gonadotropin
(HCG) to maintain the follicle and hormone produc-
tion, these drugs are used to treat infertility in women
with functioning ovaries whose partners are fertile.
Fertility drugs also may be used to stimulate multiple
follicle development for the harvesting of ova for in vitro
fertilisation.
Cetrorelix inhibits premature LH surges in women
undergoing controlled ovarian stimulation by acting as
a GnRH antagonist. Chorionic gonadotropin is used to
stimulate ovulation by acting like GnRH and affecting
FSH and LH release. Follitropin alfa and follitropin beta
are FSH molecules; they are injected to stimulate folli-
cular development in the treatment of infertility and for
harvesting of ova for in vitro fertilisation. See Table 40.2
for usual indications for each fertility drug.
Pharmacokinetics
These drugs are well absorbed and are treated like
endogenous hormones within the body, undergoing
hepatic metabolism and renal excretion. Drugs that are
available in injectable form include cetrorelix, chorionic
gonadotrophin, choriogonadotropin alpha, follitropin
alfa, follitropin beta, lutropin alfa and ganirelix. Clomi-
phene is available as an oral agent.
Contraindications and cautions
These drugs are contraindicated in the presence of
primary ovarian failure (
they only work to stimulate
functioning ovaries
); thyroid or adrenal dysfunction
because of the effects on the hypothalamic–pituitary
axis
; ovarian cysts
, which could be stimulated and
become larger due to the effects of the drugs
; pregnancy
due to the potential for serious fetal effects
; idiopathic
uterine bleeding,
which could represent an underlying
problem that could be exacerbated by the stimulatory
effects of these drugs
; and known allergy to any fertility
drug
to avoid hypersensitivity reactions
.
Caution should be used in women who are breast-
feeding
because of the risk of adverse effects on the baby,
in those with thromboembolic disease
because of the risk
of increased thrombus formation
, as well as in women
with respiratory diseases
because of alterations in fluid
volume and blood flow that could overtax the respira-
tory system.
TABLE 40.2
DRUGS IN FOCUS Fertility drugs
Drug name
Dosage/route
Usual indications
cetrorelix (Cetrotide)
3 mg SC during early follicular phase or
0.25 mg SC on day five or six of stimulation
and then every day until human chorionic
gonadotropin (HCG) is administered
Inhibition of premature luteinising hormone
(LH) surges in women undergoing
controlled ovarian stimulation
choriogonadotropin alfa
(Ovidrel)
250 mcg SC, timing depending on indication
Induction of final follicular maturation and
ovulation induction in infertile women
chorionic gonadotrophin
(Pregnyl)
500–10,000 International Units SC depending
on timing and indication
Stimulation of ovulation, hypogonadism,
prepubertal cryptorchidism
clomiphene (Clomid
and others)
50–100 mg/day PO, with length of therapy and
timing dependent on the particular situation
Treatment of infertility; also found to
be effective in the treatment of male
infertility
follitropin alfa (Gonal-F)
75–150 International Units/day SC, dose
increases based on response; do not exceed
300 International Units/day
Stimulation of follicular development in the
treatment of infertility and for harvesting
of ova for in vitro fertilisation
follitropin beta (Follistim)
75–225 International Units/day SC, dose
increases based on response; do not exceed
300 International Units/day
Stimulation of follicular development in the
treatment of infertility and for harvesting
of ova for in vitro fertilisation
ganirelix (Orgalutran)
250 mcg/day SC during early follicular phase
Inhibition of premature LH surges in
women undergoing controlled ovarian
hyperstimulation as part of a fertility
program
lutropin alfa (Luveris)
75 units SC with follitropin alfa
Used in combination with follitropin alfa to
stimulate follicle development and help
to prepare the uterus for implantation
menopausal
gonadotrophin
(Menopur)
75–150 International Units/day SC for at least
7 days, dose increased based on response;
do not exceed 225 International Units/day
Treatment of anovulatory fertility and
controlled ovarian hyperstimulation to
induce multiple follicle development
