Drugs Used In Infertility Treatment

1 Drugs Used in Infertility Treatment

There are many drugs used in the treatment of infertility. Although in most countries similar drugs are used, they may have different brand names. This complicates matters when trying to discuss the various drugs available. Here we will discuss the broad groups of drugs available, their function and side effects and give examples of some of these. Drugs for infertility can be taken orally in tablets or capsule form or by injection.

Though these medicines can be used alone for the treatment of infertility, they are mainly used in conjunction with various techniques for assisted conception. These drugs can also be used in combination with each other. As with most treatments for infertility, drugs increase the likelihood of multiple pregnancies such as twins or triplets.

Drugs Used By Women

1. Ovulation Induction Drugs

Many women fail to ovulate or have unpredictable ovulatory cycles. This is a common cause for referral to an assisted conception unit. These drugs are therefore used to stimulate the ovaries and trigger ovulation. They may be used alone or in conjunction with Artificial Insemination (AI) or an Assisted Reproduction Technology (ART) such as IVF or ICSI. Ovulation inducing drugs are used for women with ovulation failure who are under 40 years of age.

The main drug in this group is Clomiphene citrate. This is sometimes known as Clomid or Serophene, which are brand names. It is the oldest and most widely used of all drugs in infertility treatment and has been around for approximately 30 years. It is taken in tablet form, initially at a dose of 50 milligrams per day for 5 days. You usually start taking the first dose on Day 3, 4 or 5 of your menstrual cycle. Ovulation occurs approximately 7 days after completing the 5 day course. If ovulation does not occur, the dose may be increased in 50 milligram steps each month to a maximum dose of 150 milligrams per day. It is usually used for no longer than 6 cycles. If no ovulation has occurred, other drugs may then be tried.

Clomiphene works by suppressing oestrogen. This has the effect of triggering the hypothalamus to release GnRH, which in turn triggers the pituitary to release follicle stimulating hormone (FSH) and Luteinising Hormone (LH), thereby stimulating the ovaries. Ovulation occurs in approximately 60-80% of women, mostly within the first 3 cycles.

Side effects are usually mild but can include;

hot flushes,
mood swings,
blurred vision,
nausea,
bloating,
breast tenderness,
headaches,
insomnia,
increased urination,
heavy periods,
acne,
weight gain,
changes to cervical mucous.

2. Pituitary Stimulating Drugs

This group mainly consists of pulsed gonadotrophin releasing hormone (GnRH). Brand names for these include Gonadorelin, Factrel and Lutrepulse. These are usually given using a small pump worn on the upper arm. This delivers a precise "pulse" of the drug into the bloodstream. This stimulates egg production in the ovaries by stimulating the pituitary gland to secrete FSH and LH. These drugs are mainly used when their is failure to produce natural GnRH by the hypothalamus.

Possible side effects include;

headaches,
abdominal pains,
nausea and vomiting,
heavy periods.

3. Ovary Stimulators

There are several drugs in this group. These drugs contain FSH, either alone or in combination with LH. Examples of brand names include; Gonal-F, Puregon, Menogon, Menopur, Merional, Follistim, Fertinex and Bravelle. They are given by injection, either intra-muscularly (into a muscle) or sub-cutaneously (under the skin). Although they are usually given by a doctor or nurse, patients can be trained to self administer these injections at home.

Once the eggs have matured, another drug called human chorionic gonadotrophin (hCG) is also given as a single injection. This triggers ovulation to occur.

These drugs are used if your ovaries fail to respond to clomiphene and if you;

require ovulation to be stimulated for treatment cycles
have polycystic ovarian syndrome (PCOS).

These drugs can also be used when there is a failure of the pituitary gland or in some cases of male infertility.

Side effects can include;

ovarian hyper-stimulation syndrome (OHSS) - see below,
multiple pregnancy,
allergies,
skin reaction.

4. Cycle Suppressant Drugs

These drugs do not in themselves treat infertility but are used to give more control over treatment cycles. They can for example be used to stop the menstrual cycle if required. They are sometimes also known as gonadotrophin releasing hormone analogues (GnRH analogues). They block or inhibit the release of FSH and LH from the pituitary gland. Examples include Goserelin and Burserelin. They can be taken in nasal spray form or by injection in either daily or monthly formulations. They can also be used at the same time as the fertility drugs described above.

Side effects can include;

hot flushes,
headaches,
night sweats,
mood swings,
vaginal dryness,
acne,
changes in breast size,
aches & pains.

5. Drugs That Maintain Pregnancy

These drugs all contain the hormone progesterone. This thickens the lining of the womb (the endometrium) in preparation for implantation of a fertilised egg (embryo). Examples of these drugs include; Cyclogest, Gestone, Crinone and Progynova. These drugs come in vaginal pessary, gel, tablet or injectable forms. They are given after a dose of hCG or on the day of transfer of the embryos back into the uterus after an ART procedure.

Side effects can include;

nausea and vomiting,
swollen and painful breasts.

6. Other Drugs

There are several other types of drugs that may be used in various situations. These are not in themselves infertility drugs but may have a role to play in leading to a successful delivery. They include;

aspirin: this may reduce the risk of miscarriage in certain women,
heparin: this is used to thin blood (usually in patients who have blood clots or thrombosis). However, it may have a role in reducing miscarriage rates in those women who have recurrent spontaneous miscarriages,
Bromocriptine and Cabergoline: these drugs are used to reduce levels of the hormone prolactin in those with prolactin secreting pituitary tumours. They can also reduce the size of these tumours.

Drugs Used By Men

Drugs play a far lesser role in the treatment of male infertility than in females. They are used in certain specific situations.

1. Antibiotics: to treat various infections that may be responsible for inadequate sperm production,

2. Vitamins C & E: although there is little evidence of their benefit in improving pregnancy rates, these vitamins are sometimes used to improve sperm motility (movement),

3. Gonadotrophin: this can be given as injections or through a pump and is occasionally used in instances when there is no sperm production.

Ovarian Hyper-Stimulation Syndrome (OHSS)

This is a well recognised potential side effect of trying to artificially stimulate the ovaries to produce eggs for ovulation. It occurs with the use of some of the infertility drugs described above. This condition can be dangerous and usually requires hospital assessment and monitoring in severe cases.

Fertility drugs over react and excessively stimulate the ovaries. Multiple cysts develop on the ovaries and fluid builds up in the abdomen. In more severe cases, the ovaries swell and fluid fills the abdomen and chest cavities. There then develops a risk of blood clots and kidney damage.

Symptoms include;

abdominal swelling or distention
nausea and vomiting
abdominal pain
breathlessness
feeling faint

Women who are taking infertility drugs and who experience these symptoms should contact their clinic immediately. Treatment for infertility will usually be stopped. In severe cases, you may require urgent admission to hospital.