Despite the initial qualification and stimulation conducted under medical supervision, the process of stimulation does not always proceed as expected. The ovarian response to the medications may be too weak or excessive.
The ovarian response to the medications may be insufficient; few follicles may develop or – very rarely – the ovaries may not respond to the stimulation at all, with the result that only small number of egg cells will be picked up, or even that the stimulation will be discontinued before ovum pick-up.
The treatment may be discontinued earlier also in the case of excessive ovarian response to the stimulation. The continuation of the treatment in this situation carries a high risk of hyperstimulation syndrome. Each time the stimulation is ended prematurely, the patients should report to the doctor in order to determine the further course of the medical procedure.
Drug side effects are caused by the inhibition of sex hormones secretion (related mainly to the long-term therapy with these hormones) and include: hot flushes, spotting or bleeding, vaginal dryness, fatigue, decreased libido, sporadic increase in aminotransferase activity and slight increase in cholesterol level, sensory disorders, vision disorders, weight gain, muscle and joint pain, nausea, vomiting, swelling, headache, depression. Occasional allergic reactions have been observed (pruritus, rash, skin redness, fever, very rarely anaphylactic shock). In single cases, there may be transient injection site pain.
As the drugs are administered after ovulation, there is the possibility that they will be used in early pregnancy.
Therefore it is safer to use other methods of contraception (e.g. condoms) starting from the month in which an agonist is introduced. Although no fetal defects resulting from the therapy with these drugs have been reported, they should be discontinued once the pregnancy is confirmed.