Superovulation Intrauterine Insemination (IUI)
Gonadotropins are injectable follicle-stimulating hormones that are identical to the hormone FSH produced by the body. This treatment results in the recruitment and growth of multiple follicles, which are structures that contain eggs,in the ovaries.This is termed “super ovulation”. In addition to increasing the number of eggs, the timing of ovulation can be controlled to maximize the chances of pregnancy by the administration of HCG (Chorionic Gonadotropin®), when the follicles have grown to a size consistent with egg maturity. Intrauterine insemination (injection of sperm into the uterus) is always performed in combination with superovulation and has been shown to optimize the pregnancy rates in superovulation cycles.
Several preparation of gonadotropins are available include Gonal-F®, Puregon® and Menopur®. Gonadotropins are also used in IVF cycles where many eggs are required.
All gonadotropin superovulation cycles must be administered and monitored by an infertility specialist. They are monitored with blood estrogen levels and pelvic ultrasounds to assess follicular growth. These tests are performed every few days in the early part of the stimulation cycle. Towards the end of the cycle they are performed more frequently, depending upon each patient’s individual response. Ovulation induction cycles are followed by an injection of HCG to trigger ovulation. Intrauterine insemination is performed 36-38 hours after hCG administration. In an IVF cycle, egg retrievals are also timed using hCG, however an egg retrieval is performed before the eggs are released by the ovaries.
The most common side effects with superovulation include discomfort or “fullness” in the lower abdomen, bloating, headache or fatigue. The most significant potential risks are multiple pregnancies and ovarian hyperstimulation syndrome (OHSS). The majority of multiple pregnancies are twins; however, occasionally more than two fetuses can sometimes develop. Pregnancy with three or more fetuses places both the mother and fetus at high risk of miscarriage, preterm delivery and bleeding. The risk of high order multiples is higher in superovulation cycles than IVF cycles because the number of eggs ovulated cannot be precisely controlled. If too many follicles are growing during a super ovulation cycle, the cycle may have to be cancelled due to the risk of multiple pregnancy. Another option may be to convert the cycle to in vitro fertilization (IVF), where the eggs can be harvested and replacing a one to two embryos thus reducing the risk of a high multiple pregnancy.
Ovarian hyperstimulation may typically occur 5-7 days after hCG injection. This is triggered by pregnancy and is seen in about 1% of superovulation cycles. Pregnancy following a superovulation cycle may increase the risk of OHSS as the pregnancy hormone HCG may stimulate the ovaries. In general, the symptoms associated with ovarian hyperstimulation are mild and may include lower abdominal pain, heaviness and bloating. Sometimes shortness of breath may also develop. Close monitoring of the ovarian stimulation by ultrasound and laboratory tests are used to minimize the risk of ovarian hyper stimulation. Very occasionally a blood clot can result from this disorder, so women at risk may be placed on a short course of a blood thinner (heparin).
Informed consent is needed so that patients understand the risks and benefits involved in treatment with intrauterine insemination. It is therefore required that you have received, signed and witnessed important information regarding the use of reproductive material (sperm, eggs or embryos) as outlined in the “Assisted Human Reproduction Regulations on Consent“.
Check out our frequently asked questions (FAQ’s) for further information regarding your superovulation/IUI cycle.