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Clomiphene Citrate

Clomiphene Citrate is the most common fertility drug given for women who do not ovulate (release eggs) regularly.

It works as an anti-estrogen which diminishes negative feedback to the brain and lead to increased release of gonadotropins (hormones that stimulate the ovary to grow follicles and ovulate). It will result in ovulation in 80% of women.

The usual dose is 50- 150 mg/ day, and is given for 5 days.

  • It usually starts from the 2nd day of the menses.
  • It is generally well tolerated but some side effects may occur like thinning of the lining of the uterus, and thickening of cervical mucus.
    • Rarely it may cause symptoms like transient hot flushes (10%), and even rarer are symptoms like breast tenderness, pelvic pressure or pain or visual disturbance.
    • It may also result in twin pregnancy in 5-8% of women.
Timing of Ovulation (TOO)

Procedure is done using a transvaginal ultrasound scan to assess the response of a woman treated with Clomiphene Citrate

  • Usually starts on day 12 of the menstrual cycleto check if a dominant follicle is developing from the current dose of clomiphene
  • This is repeated every 2-3 days up until the follicle reaches a diameter of about 18mm or, if no dominant follicle emerges by the 20th day of menses monitoring is discontinued
  • Adjustment on the dose of the clomiphene or even a change in the form of treatment (i.e. fertility injections) will be done for the subsequent cycles depending on the results.
Intra-uterine insemination (IUI)

1. Who is suitable for intrauterine insemination?

It is useful when the patient's spouse has mild or moderate sperm problems.

2. What does the process involve?

  • In the woman, it involves doing serial ultrasound scan to monitor the growth of the follicle (which contains the egg) to detect ovulation. Once the size of the ovarian follicle reaches 18mm, she will then be given a subcutaneous injection, hCG, to mature the egg within the follicle.

  • The husband will have to produce semen sample on the morning of the IUI. The sample will then be prepared in the laboratory so that the best quality sperm are selected.

  • Intrauterine insemination will then be performed 36 - 40 hours after the injection.

  • The procedure itself is quick and painless. A speculum will be placed in the vagina to visualise the cervix. The sperm preparation is then placed in the uterus using a thin catheter.

3. What if the husband is not around during the IUI?

It is possible for the husband to provide semen sample in advance and for the specimen to be frozen. On the day of the IUI, the sample will be thawed and prepared in the usual way. This avoids the problem of the husband being absent on the day of the IUI.
However, it is usually advisable to provide fresh semen sample.
The other option is to cancel the cycle and try again when the husband is around.

4. What are the risks of Intrauterine insemination?

Natural cycle IUI does not pose much risk at all.
Stimulated IUI can lead to multiple follicular growth, and therefore increasing the chance of a multiple pregnancy.

5. What is the success rate of IUI?

The success rate for this procedure is approximately 9% per cycle.

6. How many times can a couple try IUI?

IUI can be attempted as many times as the couple wishes.
However, the likelihood of success decreases with increasing numbers of failed IUI.

The couple must remember that increasing woman's age reduces fertility.
The current recommendation is to try 3 cycles of IUI and proceed to in vitro fertilization (IVF) if unsuccessful.

7. How much does it cost?

In NUH, the cost of IUI procedure is about SGD$660-$760, excluding GST.
Please note that the cost excludes doctor consultation fee, medication and other investigation costs. 

For more information on the preparation for the IVF programme, overview of the IVF schedule, risks and complications and the protocols, please click here to read our patient education brochure.
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