Complications of infertility

Some infertility treatments can cause complications. These are outlined below.

Side effects of medication

Some of the medications that are used to treat infertility can cause side effects. These may include:

  • nausea
  • vomiting
  • diarrhoea
  • stomach pains
  • headaches
  • hot flushes

For a full list of possible side effects, please see the patient information leaflet that comes with your medication, or see Medicines information

Ovarian hyperstimulation syndrome

Ovarian hyperstimulation syndrome (OHSS) can occur after taking medicines that stimulate your ovaries, such as clomifene and gonadtrophins, and can develop after a round of in-vitro fertilisation (IVF). OHSS causes your ovaries to swell and produce too many follicles (small fluid-filled sacs in which an egg develops).

Around one-third of women will experience mild OHSS after one cycle of IVF. Less than 10% will develop moderate or severe OHSS after one cycle of IVF. 

Mild symptoms may include:

  • nausea 
  • vomiting
  • abdominal pain
  • bloating
  • constipation (when you are unable to empty your bowels)
  • diarrhoea
  • dark, concentrated urine

Severe OHSS is a potentially life-threatening condition and can lead to:

  • thrombosis (a blood clot in an artery or vein)
  • liver and kidney dysfunction
  • respiratory distress (difficulty breathing)

You should seek medical attention immediately if you experience any of the symptoms of OSHH.

You may need to go to hospital so that your condition can be monitored and you can be treated by healthcare professionals.

Ectopic pregnancy

"Ectopic" means in the wrong place. An ectopic pregnancy occurs when the fertilised egg implants outside your womb. More than 95% of ectopic pregnancies occur in the fallopian tubes.

If a fertilised egg implants itself in your fallopian tube and continues to grow, it can result in a miscarriage, and there is a risk of the tube bursting. Signs of an ectopic pregnancy include:

  • pains low down in your stomach
  • vaginal bleeding

Speak to your GP if you experience either of these symptoms early in your pregnancy.

If you are receiving fertility treatment, your chance of having an ectopic pregnancy is around 4%. This is higher than the usual rate of ectopic pregnancies, which is around 1%. You may be more likely to have an ectopic pregnancy if you have already had problems with your fallopian tubes.

Pelvic infection

The procedure to extract an egg from an ovary may result in a painful infection developing in your pelvis. However, the risk of a serious infection occurring is very low. For example, there is likely to be less than one serious infection for every 500 procedures that are performed.

Multiple pregnancy

Having more than one baby may not seem like a bad thing, but it does significantly increase the risk of developing complications for both you and your children. Multiple pregnancy is the greatest health risk of fertility treatment.

Possible complications of multiple pregnancy include:

  • Babies born prematurely or with a low birth weight. This affects 50% of twins and 90% of triplets.
  • Your baby dying within the first week of life. The risk of this happening is five times higher for twins, and nine times higher for triplets, than for a single baby.
  • Your baby having cerebral palsy (a condition that affects the brain and nervous system). The risk of this happening is five times higher for twins and 18 times higher for triplets than for single babies.
  • High blood pressure (hypertension) during pregnancy. This affects up to 25% of women who are carrying more than one baby.
  • Developing diabetes during the pregnancy (diabetes is a condition that is caused by too much glucose in the blood). The risk is two to three times higher for women who are carrying more than one baby than it is for those who are carrying a single baby.

In the UK, one in four births after IVF results in twins or triplets. This is higher than the usual rate of multiple pregnancy, which is around one in 80 births.


Infertility can be very stressful and it can put a lot of strain on relationships. It may be helpful for you to join a support group where you can talk through your feelings with others who are experiencing similar problems.

Finding out that you have a fertility problem can be traumatic and many couples find that is it helpful for them to talk to a counsellor. The counsellor will be able to discuss treatment options with you, how they may affect you and the emotional implications. Your GP should be able to refer you to a counsellor as part of your fertility treatment.

Ovulation is when an egg is released from a woman's ovaries.

The ovaries are two small, round organs in the female reproductive system that release an egg every month.

Fallopian tubes
The tubes connecting the ovaries to the womb.

The womb (or uterus) is a hollow, pear-shaped organ in a woman where a baby grows during pregnancy.

IVF stands for in vitro fertilisation. An egg is surgically removed from a woman and fertilised by a sperm outside of the body.



Last updated: 04 October 2011

Continue to next section: Preventing infertility