Changes in demographic trends in the age at first pregnancy in our times have combined to yield more and more women seeking pregnancy when they are older and less fertile. Numerous studies in recent years have demonstrated that fertility declines progressively as age advances. In IVF, the main focus of attention is on assessment of what is termed the ovarian reserve. Ultraso-nography is now being used to investigate follicular dynamics in aging women as are detailed endocrine-based tests (24). A decrease in the ovarian reserve, or number of follicles capable of being stimulated, is a primary reason for declining fertility. Similarly, the ovarian response to exogenous gonado-trophin stimulation also decreases, but the range of individual variation is extremely wide and it is well known that age is only a rough guesstimate of the ovarian reserve and hence the ovarian stimulation response.
There are several tests of "ovarian reserve'' that include clomiphene citrate challenge and the GnRH agonist stimulation tests (24-27). Ovarian biopsy is available, although it remains controversial (24,28). The endocrine tests offer prognostic information valuable in the counseling of aging infertile women. However, there is much recent evidence to suggest that ultraso-nography may be used to estimate the number of antral follicles at specific times of the menstrual cycle and provide additional useful information of clinical relevance (29-32). Ultrasound assessments take place using antral follicle counts or measurement of ovarian volume. Early follicular-phase antral follicle counts, typically done on days 3 to 7 post-menstruation, may be used to predict the number of follicles likely to develop during ovarian stimulation with exogenous gonadotrophins (31,33-36). Women having fewer than five follicles under 10 mm in diameter before ovarian stimulation begins have a relatively poor prognosis for success (35). Studies to determine the extent to which antral follicle counts correlate with endocrinologic measures of ovarian reserve (e.g., cycle day 3 FSH and estradiol concentrations) remain to be widely confirmed (30). Ovarian volume assessments are based on the presumption that there is a significant correlation between the population of primordial follicles remaining in the ovary and the volume of the ovary, measured using either two- or three-dimensional ultrasonography (27,29,33,37). A very clear relationship between decreased ovarian volume and antral follicle counts and advancing age combined with increased FSH has been demonstrated (26,30). Although there remains a good deal of work yet to do in order to standardize the imaging based assessments, ultrasonography remains an important aspect of ovarian reserve estimation and prediction of the probability of a successful ovarian stimulation cycle (35).
Was this article helpful?
Prior to planning pregnancy, you should learn more about the things involved in getting pregnant. It involves carrying a baby inside you for nine months, caring for a child for a number of years, and many more. Consider these things, so that you can properly assess if you are ready for pregnancy. Get all these very important tips about pregnancy that you need to know.