- Human gonadotrophic hormone (HCG), which is produced by the early pregnancy tissues, keeps the corpus luteum functioning (Q 2.13).
- HCG is almost identical chemically to LH.
- It is a surge of LH that normally results in ovulation (Figure 2.3).
- When there is evidence of follicular development with clomiphene but ovulation or pregnancy do not occur, HCG administration can increase the chance of conception.
- The HCG should be given when the leading follicle reaches approximately 18mm diameter as visualised by ultrasound.
Related Medical Abstracts - Click on the paper title:-
- Clomiphene citrate monitoring for intrauterine insemination timing: a randomized trial. (2006-01)
- Women with ovulatory dysfunction undergoing ovarian stimulation with clomiphene citrate for intrauterine insemination may benefit from administration of human chorionic gonadotropin. (2005-01)
- Is waiting for an endogenous luteinizing hormone surge and/or administration of human chorionic gonadotrophin of benefit in intrauterine insemination? (1999-01)
- Intrauterine insemination: Effect of the temporal relationship between the luteinizing hormone surge, human chorionic gonadotrophin administration and insemination on pregnancy rates (1997)
- Human menopausal gonadotropin and the risk of epithelial ovarian cancer (1996)
- Time interval from human chorionic gonadotrophin (HCG) injection to follicular rupture (1995)
- Ultrasound timing of human chorionic gonadotropin administration in clomiphene-stimulated cycle (1982)
- Therapeutic induction of ovulation: towards the replacement of hCG with LH (1994)
- Evaluation of whether using hCG to stimulate oocyte release helps or decreases pregnancy rates following intrauterine insemination (1994)
- Evaluation of clomiphene citrate and human chorionic gonadotropin treatment: a prospective, randomized, crossover study during intrauterine insemination cycles (1994)
- A controlled study of human chorionic gonadotrophin induced ovulation versus urinary luteinizing hormone surge for timing of intrauterine insemination. (1991-01)
- Ultrasound timing of human chorionic gonadotropin administration in clomiphene-stimulated cycle (1982-01).
Ovulation Induction - Summary
With the exception of primary ovarian failure (the menopause), ovulatory disorders can usually be successfully treated. Ovulation induction regimens depend on the underlying cause (infertility cause).
Sometimes appropriate advice may be all that is required. When weight loss is responsible for secondary amenorrhoea (amenorrhoea causes), improved diet leading to correction of your weight may prove to be successful.
The main drugs used to overcome anovulation are clomiphene (clomiphene)(clomiphene citrate), tamoxifen (tamoxifen infertility), bromocriptine (bromocriptene), metformin (12), and gonadotrophins (gonadotrophins).
risks of ovulation induction
There are three concerns associated with drugs used to induce ovulation:
- They are associated with a greater chance of multiple pregnancy. The general rate of twins in the population is one in every eighty deliveries but with clomiphene, it is one in twenty or a four-fold increase. Higher order multiple pregnancies (e.g. triplets and quads) can occur with clomiphene but this is rare. Injections of gonadotrophins are more likely than clomiphene to result in multiple pregnancy.
- Occasionally ovulation induction can lead to ovarian hypersensitivity syndrome (OHSS).
- Finally, there has been concern that ovulation induction treatments may increase the chance of ovarian cancer. A comparison was made of the risk of cancer among women who received clomiphene with the risk among infertile women who did not receive it. There were 11 invasive or borderline malignant ovarian tumors, as compared with an expected number of 4.41994-01. A confounding factor is that infertility is itself associated with an increased risk. Furthermore, the risk is reduced with secondary infertility and is dependent on the causation of the infertility.2004-01Several infertility units have reported their data. Some seemed to confirm the link between clomiphene and ovarian cancer but the majority have produced reassuring results.1999-02,2004-02 2006-01
Related Medical Abstracts - Click on the paper title:-
- Induction of ovulation and ovarian cancer: a critical review of the literature. (2006-01)
- Ovarian cancer risk associated with varying causes of infertility.(2004-01)
- Ovarian cancer risk after the use of ovulation-stimulating drugs.(2004-02)
- Fertility drugs and the risk of breast and ovarian cancers: Results of a long-term follow-up study. (1999)
- Ovulation induction and ovarian tumours: the debate continues.(1999-02)
- Ovulation induction, infertility, and ovarian cancer risk (1996)
- The risk of ovarian cancer after treatment for infertility (1995)
- Ovarian stimulation and ovarian tumours: a critical reappraisal (1995)
- Ovarian tumors in a cohort of infertile women (1994)
- Characteristics relating to ovarian cancer risk: Collaborative analysis of 12 US case-control studies. II. Invasive epithelial ovarian cancers in white women (1992)
Related Medical Abstracts - Click on the paper title:-
- Ovulation induction using s.c. pulsatile gonadotrophin-releasing hormone: Effectiveness of different pulse fre quencies (1996)
- Investigation and treatment of amenorrhoea resulting in normal fertility (1979)
Ovulation Induction Monitoring
Monitoring may be required to confirm that ovulation is occurring and to ensure that too many follicles are not developing. Blood tests for progesterone levels around the twenty-first day of the cycle provide an indication of ovulation (Q9.17). Ultrasound monitoring of follicular development is helpful with tablet treatment (clomiphene and tamoxifen) and is really essential with gonadotrophins. When controlled ovarian hyperstimulation is undertaken in IVF protocols, oestradiol levels are used. The need for monitoring hormone levels in IVF protocols has been questioned.1998-01, 2006-01
Related Medical Abstracts - Click on the paper title:-
- Monitoring ovarian stimulation: are hormonal assessments necessary? (2006-01)
- Follicle tracking of women receiving clomiphene citrate for ovulation induction. (2005-01)
- The role of infertility nurses in ovulation induction programmes (2001)
- Comparison of several one-step home urinary luteinizing hormone detection test kits to OvuQuick. (2001-02)
- The usefulness of a urinary LH kit for ovulation prediction during menstrual cycles of normal women. (1996-01)
- Is it possible to run a successful ovulation induction program based solely on ultrasound monitoring? The importance of endometrial measurements (1991-01)
- The clinical value of Clearplan home ovulation detection kits in infertility practice. (1991-02)
- Single serum progesterone measurement in the mid-luteal phase as an index of ovulation.(1987-01)
- Plasma progesterone levels as an index of ovulation. (1983-01)
- The value of a single serum progesterone measurement in the midluteal phase as a criterion of a potentially fertile cycle ("ovulation") derived form treated and untreated conception cycles. (1982-01)
- Plasma oestradiol and progesterone estimation for the monitoring of induction of ovulation with clomiphene and chorionic gonadotrophin. (1975-01)
