A risk of ovarian stimulation is the development of ovarian hyperstimulation syndrome, particularly if hCG is used for inducing final oocyte maturation. This results in swollen, painful ovaries. It occurs in 30% of patients. Mild cases can be treated with over the counter medications and cases can be resolved in the absence of pregnancy. In moderate cases, ovaries swell and fluid accumulated in the abdominal cavities and may have symptoms of heartburn, gas, nausea or loss of appetite. In severe cases, patients have sudden excess abdominal pain, nausea, vomiting and will result in hospitalisation.
During egg retrieval, there exists a small chance of bleeding, infection, and damage to surrounding structures such as bowel and bladder (transvaginal ultrasound aspiration) as well as difficulty in breathing, chest infection, allergic reactions to medication, or nerve damage (laparoscopy).
Ectopic pregnancy may also occur if a fertilised egg develops outside the uterus, usually in the fallopian tubes and requires immediate destruction of the foetus.
IVF does not seem to be associated with an elevated risk of cervical cancer, nor with ovarian cancer or endometrial cancer when neutralising the confounder of infertility itself. Nor does it seem to impart any increased risk for breast cancer.
Regardless of pregnancy result, IVF treatment is usually stressful for patients. Neuroticism and the use of escapist coping strategies are associated with a higher degree of distress, while the presence of social support has a relieving effect. A negative pregnancy test after IVF is associated with an increased risk for depression, but not with any increased risk of developing anxiety disorders. Pregnancy test results do not seem to be a risk factor for depression or anxiety among men when the relationships is between two cisgender, heterosexual people. Hormonal agents such as gonadotropin-releasing hormone agonist (GnRH agonist) are associated with depression.
Studies show that there is an increased risk of venous thrombosis or pulmonary embolism during the first trimester of IVF.  When looking at long-term studies comparing patients who received or did not receive IVF, there seems to be no correlation with increased risk of cardiac events. There are more ongoing studies to solidify this.
Spontaneous pregnancy has occurred after successful and unsuccessful IVF treatments. Within 2 years of delivering an infant conceived through IVF, subfertile patients had a conception rate of 18%.