Fertility drugs are used to stimulate the follicles in the ovaries resulting in
the production of multiple eggs in one cycle. The medications also control the
time that the eggs are released (ovulation), so sexual intercourse,
intrauterine inseminations, and in vitro fertilization procedures can be
scheduled at the most appropriate time to achieve pregnancy.
Clomiphene Citrate - This medication comes in a tablet form and is used to
stimulate the ovaries to produce eggs.
HCG is an injectable
medication that is used to induce the release of the egg once the follicles are
developed and the eggs are mature.
Other drugs which may be prescribed alongwith the above mentioned treatment,
Metformin (an anti diabetic drug) is given to patients as a serum insulin
lowering medication. Most commonly used in PCOS
patients and has been shown to be effective within two or three months.
Bromocryptine or Cabergoline is an oral medication used to lower serum
prolactin levels. It will also reduce the size of a pituitary tumor,
should one be present.
There are different levels of ovulation induction commonly used to treat
infertility related to ovulation disorders, male factor or unknown causes. The
first level of ovarian stimulation involves Clomiphene citrate taken in pill
form for 5 days at the beginning of a cycle. Clomiphene is used to stimulate
the ovaries to produce the eggs. For women whose only infertility
problem is anovulation, up to 80% of patients will ovulate using this
medication and 40% of those will conceive.
The next and more aggressive level of ovulation induction is called
superovulation. This treatment uses gonadotrophins or sometimes a combination
of clomiphene and gonadotropins (FSH/HMG)
to stimulate the production of multiple eggs. The development of the follicles
and endometrium (lining of the womb) are closely monitored by blood tests and
ultrasounds to helps the physician administer the correct dosage of medication.
When the leading follicle measures 18-mm in diameter and the endometrium is
well developed, a HCG injection is given to time insemination. HCG is an
injectable medication that is used to induce the release of the egg.
Ovulation will occur between 24-36 hours after HCG. The patient is instructed to
either have intercourse during this time (if the
PCT is normal) or to come in for an intrauterine
insemination (IUI) . Depending on the cause of infertility, the success rate
per superovulation treatment cycle is approximately 20-25% per cycle.
There is evidence that intrauterine
insemination (IUI) with ovarian stimulation results in higher success
rates than IUI only. The precise timing of insemination is very important and
is done either when ovulation is imminent or just after.