This investigation is the first to show a positive, albeit weak, correlation between baseline serum AMH levels and subsequent blastocyst development during IVF. Although serum AMH has found increasing application as a predictor of ovarian reserve, its role in forecasting in vitro
embryo morphology and developmental potential to the blastocyst stage is still emerging. For example, Riggs et al
] found AMH to be a useful biomarker to predict low vs. high responders among oocyte donors, but not predictive of embryo morphology or pregnancy outcome in the recipient population. Similarly, while an earlier study reported basal serum AMH as useful in predicting oocyte number and quality, further cleavage up to the blastocyst stage was not affected by AMH [14
]. In contrast, the current investigation suggests that baseline serum AMH determinations can indeed be extended to estimate blastocyst developmental potential during IVF. A trend of somewhat lower patient age where no blastocyst transfer was possible represents an unexpected finding from our study, and underscores the limitations of using patient age alone as a method to predict blastocyst development.
Clinicians and researchers continue to search for improved methods to estimate ovarian reserve and predict reproductive outcome. Serum AMH may help solve this challenge, as it is maximal in females at puberty but progressively decays throughout reproductive life [15
]. Indeed, physiologic menopause or surgical removal of functional ovaries will render serum AMH essentially undetectable within days [4
]. More recently, specific polymorphisms of the AMH receptor have been implicated as additional modulators of sex-steroid activity [18
]. Early determination of reserve is useful not only because this information helps guide patient counselling, but it also assists in calibrating the gonadotropin doses for IVF patients. Risks of poor follicular recruitment [19
] and ovarian hyperstimulation [20
] would be minimised by accurate and reliable prediction of ovarian response in IVF. Since serum AMH levels might help estimate ovarian response for non-IVF patients as well [22
], this test has emerged as an increasingly important element of basic fertility assessments. When best to assess serum AMH has also been studied, but baseline measurement seems to be the most predictive marker for ovarian response [23
]. Whether or not serum AMH can be validated as the definitive biophysiologic test to predict the age of menopause remains the subject of active study and debate [24
Several limitations of this research should be noted. First, we did not stratify study subjects by infertility aetiology, although evidence suggests that different types of reproductive pathology might impact serum AMH in different ways. For example, ovarian response to gonadotropins is often attenuated in the setting of endometriosis, and serum AMH is reduced in fertility patients as a function of severity of the disease [26
]. In contrast, polycystic ovary syndrome (PCOS) is associated with abnormally increased follicular numbers and relatively high serum AMH. This enhanced AMH production by granulosa cells in women with PCOS may be a dysfunctional manifestation of impaired access of FSH to the follicular compartment [27
]. This retrospective study did not take these factors into account. Additionally, we should note that while a trend of higher median serum AMH levels was observed among patients who conceived compared to those who did not attain pregnancy, our study was not designed to detect this difference.