Ovarian Hyperstimulation Syndrome (OHSS)

The most serious complication of the ART treatment is the ovarian hyperstimulation syndrome. This is a relatively uncommon but potentially serious complication that occurs in 2-10% of cases. In its mild form, it may only cause some abdominal distention or "bloating" feeling in the abdomen. In the more serious form, it can lead to fluid accumulation in the abdomen or the chest causing difficulty in breathing; kidney dysfunction and clotting abnormality. It can be life-threatening in its most serious form, but fortunately, this is rare.

Throughout the treatment cycle, a careful watch is kept for signs which are suggestive of a risk of developing OHSS (e.g., excessive number of follicles and a high estrogen level, excessive number of eggs collected). In high risk cases, one or more preventive measures may be needed such as: withholding the ovarian stimulation injection; cancellation of the stimulation cycle; cancellation of embryo transfer after egg collection or the use of a progestagen rather than hCG for luteal phase support.

If OHSS does occur, it usually becomes apparent within first few days after the egg collection. Symptoms of OHSS include:

• nausea and vomiting
• abdominal swelling, discomfort or pain
• concentrated and diminished urine output
• shortness of breath

Most cases are mild and require no medical treatment. However, in more serious cases, hospitalization is required.

It is important that you notify your clinic if you experience any of the above symptoms after embryo transfer!!!

^ Back To Top

Multiple Pregnancy

Since the ovaries are hyperstimulated and usually more than one embryo is put back in the uterus in order to improve the success rate, about 15% of OI/IUI pregnancy and 20% of IVF/FE pregnancy may result in multiple births. Multiple pregnancy is associated with higher obstetric risks including miscarriage, intrauterine growth retardation, congenital abnormality, premature delivery and operative delivery. The stimulation protocol and the number of embryos transferred back are thus carefully considered to reduce the risk of multiple pregnancy without compromising the success rate. Usually two or at most three embryos are placed.

^ Back To Top

Procedure Related Complications

Oocyte retrieval (egg collection) is a minor surgical procedure and it is usually without complication. However, complications may sometimes occur. These include bleeding, injury to nearby organs such as the urinary bladder, bowel and blood vessels and pelvic infection.

^ Back To Top

Fertility Drugs & Ovarian Cancer

There has been increasing concern about a possible link between the use of fertility drugs and the development of ovarian cancer. Overall, about 1 in 70 women develop ovarian cancer in their life time and the risk increases with age. The risk is higher in women with a family history of ovarian cancer and who have never had a pregnancy. Pregnancy and childbirth, use of oral contraceptive pills and breastfeeding have a protective effect. Infertile women are generally regarded as being at higher risk as they are less likely to have taken contraceptive pills and may never have had a pregnancy.

An association between fertility drug treatment (e.g. use of clomiphene citrate >12 months) and ovarian cancer has been reported in the literature although a definitive causal link has not yet been established. Infertile patients undergoing infertility treatment need to be aware that there may be a higher risk of ovarian cancer associated with infertility and infertility treatment. However, there is no effective screening method for ovarian cancer.

^ Back To Top

Congenital Abnormalities & Genetic Abnormalities of Offsprings

The incidence of congenital abnormalities in babies conceived by ART is similar to that of natural conceptions which is approximately 2%. The risk of fetal chromosomal abnormality (e.g. Down's syndrome) increases with increased maternal age (especially >35 years) and the available prenatal diagnostic tests should be discussed with you if required.

In cases of severe male factor, infrequently the male partner may have an underlying genetic problem which could be overcome by treatment with ICSI. The genetic problem could be passed on to a male child. The most common genetic diseases associated with severe male factor infertility include Kleinfelters syndrome and Y-chromosome microdeletions. Patients can enquire about testing if there is severe male factor infertility.

^ Back To Top