Monday 12 November 2007

Clomiphene Citrate

Clomiphene Citrate was one of the first infertility medications and is widely employed to induce ovulation. Originally, it was thought that it might hold potential as a birth control agent but research revealed its ovulation inducing properties.
Clomiphene Citrate works at the hypothalamus (a small organ located at the base of the brain) to cause the release of gonadotropin releasing hormone (GnRH) into the bloodstream. GnRH travels to the pituitary gland where it stimulates the release of follicle stimulating hormone (FSH). FSH stimulates the recruitment and development of eggs within the ovarian follicles. Clomiphene Citrate therapy should not be administered for more than 3- 6 months dependent upon many individual patient variables. Clomiphene Citrate studies have clearly demonstrated that pregnancy is most likely to occur during the first three months of therapy. There is little advantage to increasing the clomiphene dosage beyond that required to regulate ovulation.

Even though ovulatory dysfunction is present, a male semen analysis should be performed. Male factor is a contributor in over 47% of infertility cases and must be ruled out prior to treatment of the female. Clomiphene Citrate therapy is often administered by the non-specialist; however, it is not always the best choice and can produce unwanted side effects. Fertility physicians are trained to diagnose the various complex conditions that can cause ovulatory disorders, such as polycystic ovarian syndrome. There are also other alternatives to Clomiphene Citrate, especially in the PCOS patient where Metformin often is the drug of first choice. Clomiphene Citrate should not be administered to women over the age of 35 without a complete fertility evaluation. Fertility can decline rapidly in older female age groups. Once again, Clomiphene Citrate should not be prescribed without a male semen analysis.

Clomiphene Citrate is the most used and abused medication for infertility treatment. It was introduced to the clinical market in 1967 and almost immediately replaced the surgical procedure - wedge resection of the ovaries - for primary treatment of anovulation in patients with polycystic ovarian disease (PCOD). Clomiphene Citrate is still widely used by gynecologists for that purpose and others. It is important to remember that proper use of the medication will usually yield gratifying results while expanding its use to lesser indications may be counterproductive and often results in unsuccessful outcomes. Clomiphene Citrate's best and most common indication is for induction of ovulation in euestrogenic, normoprolactinemic, and anovulatory patients. The majority of these patients will have PCOD, which is a clinical diagnosis of chronic anovulation with symptoms and signs of Hyperandrogenism. The definition implies that there is adequate endogenous estrogen production and that hyperprolactinemia has been excluded. Patients with hypoestrogenic anovulation are not good candidates for Clomiphene Citrate as it works as an antiestrogen at the hypothalamus level.

Examples of patients with hypoestrogenism are those with premature ovarian failure, exercise-related amenorrhea, and low body weight with anorexia. Clomiphene Citrate does not work well in patients who are overweight. The second indication for clomiphene use is for the purpose of superovulation, in ovulating patients, in conjunction with assisted reproduction such as intrauterine insemination (IUI) or in-vitro fertilization (IVF). Clomiphene Citrate may also be used to treat patients with luteal phase defects in conjunction with progesterone supplementation in the luteal phase. The wide use of Clomiphene Citrate to treat patients with unexplained infertility can be counterproductive as Clomiphene Citrate can have adverse effects on the cervical mucus and on implantation at the endometrial level.

Clomiphene Citrate can be considered in young patients (< 30 years) but certainly for no longer than three cycles and with proper monitoring. Clomiphene Citrate is started at a dose of 50 mg / day for 5 days in anovulatory patients. It is important to remember that these patients do not have cycles and the conventional "cycle day 5 - 9" should not be used. Rather, the first day of clomiphene use can be conveniently called day 1 of the cycle. Patients should look for ovulation, wither by a BBT chart or using follicular studies, 7 to 10 days after the last clomiphene pill or on days 12 - 15 of the clomiphene cycle (first day of Clomiphene Citrate is day 1).

Clomiphene Citrate in some thin patients dosed at 25 mg / day for five days can be adequate. A post coital test can be performed in the first cycle of clomiphene use to check for adequate mucus production. If patients ovulate on the 50 mg clomiphene dose, they should be kept on it for 3 - 4 months before re-evaluation. If patients do not ovulate on the lower dosage,clomiphene should be increased in increments of 50 mg / day for subsequent cycles. It is important to remember that 70 -80% of patients who will respond to Clomiphene Citrate will ovulate on the 50 - 100 mg dosage and of those who get pregnant 80 - 90% will do so within 3 - 4 ovulatory cycles.

When clomiphene fails, it is extremely important to distinguish between ovulation and conception failure. Clomiphene Citrate Ovulation Failure is arbitrary defined as failure to ovulate on doses of 150 mg / day for 5 days (even though 10 - 20% of patients can ovulate on higher dosages, it is important to re-evaluate the patient at this stage)

What are our options to induce ovulation for these patients?
a)Clomid doses can be increased to a maximum of 250 mg / day for five days or consider increasing the duration (100 mg / day for 8 days).

b) Clomid does not work well in extremely obese patients (> 90 Kgs or BMI > 30).These patients usually have insulin resistance and those patients should be highly encouraged to lose weight before induction of ovulation. Insulin sensitizing agents such as Metformin (Glucomet) or Hyponidd should be the primary treatment. Metformin can be started at the dose of 850 mg / day for one or two weeks, increased to 1700 mg p.o., for the next week, and maintained at the same dose thereafter.

1 comment:

Mat said...

Anyone familiar with this fertility retreat center in Hawaii?
Called the kaNeCa Fertility Institute. Thanks - Mat