Ovulation induction (OI) is a fertility treatment that uses medications to cause or regulate ovulation, or increase the number of eggs produced during a cycle, to increase the opportunity for pregnancy.
Ovulation induction medications include clomiphene citrate. This oral drug promotes growth of the fluid-filled sacks (follicles) containing the eggs. If you do not ovulate, or you ovulate and do not become pregnant after clomiphene therapy, other medications known as gonadotropins may be prescribed, either alone or in combination.
Gonadotropins are taken by injection under the skin. They replace natural follicle-stimulating hormone (FSH), and if they are successful the ovaries produce multiple follicles and high-quality, mature eggs.
Your hormone levels and follicular development are tracked throughout the stimulation cycle. If required, your medication protocol (the type and dose) may be altered for optimum results.
Because powerful hormones are used to produce significant changes in your system, their effects are tracked by blood tests and ultrasound. These tests are used to determine a baseline – indicating your natural hormone levels – and your medication start date. For this reason, ovulation induction cycles also may be called “monitored” cycles.
When the follicles are mature, usually between 16 and 20 millimetres in diameter depending on your stimulation medication, you will take an intramuscular injection of hCG in preparation for intercourse or intra-uterine insemination (IUI).
The potential fertility improvement that this type of treatment may yield depends on the woman’s age and diagnosis and the initial male semen analysis, and should be discussed with your specialist.
Various fertility medications are available for ovulation induction, and your physician will choose the drug or combination of stimulation drugs that is best in each case. Medications include:
Ovulation induction treatment is recommended for:
Ovulation induction treatment is not recommended for:
Overstimulation – Some women may experience an excessive response by their ovaries to the fertility drugs. Ovarian hyperstimulation syndrome (OHSS) occurs in a minority of women who overrespond. Symptoms include severe discomfort, nausea, vomiting, abdominal distension and dehydration. It is important that the clinic is notified immediately if any of these symptoms occur during your treatment, as hospitalisation may be required.