Follicular fluid (FF) is a mixture of chemical constituents, comprising a variety of different proteins as well as growth factors, reactive oxygen species, anti-apoptotic factors, fatty acids, sugars, and hormones [
1]. Among them, the Anti-Mullerian hormone (AMH), a homodimeric glycoprotein which belongs to the transforming growth factor-β (TGF-β) family, has evolved to become one of the most prominent targets for reproductive health research [
2]. Anti-Mullerian hormone is secreted primarily by granulosa cells of ovarian follicles during early stages of follicle development (pre-antral and antral follicles) [
3] but has also been found in endometrial and endometriotic tissue [
4]. Females are born with a defined number of primordial follicles, whose quantity and quality define the ovarian reserve [
5]. Oocytes within primordial follicle rest in a dormant state of meiosis I until puberty, and until then, the granulosa cells do not secrete AMH. A recent study demonstrated the beginning of AMH secretion with the recruitment of the follicles [
6], with maximum AMH values at the age of 15.8 years. After a plateau phase until the age of 25 years, AMH concentrations start to decrease and inversely correlate with age. This emphasizes AMH as the most potent marker for ovarian reserve in women of 25 years and older [
7] among other parameters commonly used such as antral follicle count, follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol, or inhibin B. During the menstrual cycle serum AMH (sAMH), values remain relatively stable compared to all other hormones secreted by the ovary and can be analyzed at any day of the cycle, which is an advantage for flexible in vitro fertilization (IVF) treatment [
8].
Values of sAMH have been intensively investigated [
9,
10]; however, there is less data regarding the behavior of AMH concentrations in FF (fAMH), since FF has usually been designated as waste product during oocyte collection for IVF treatment. Recent studies revealed the importance of FF in oocyte development [
11], providing information on follicular growth, oocyte quality, and fertilization. However, in studies to date, FFs have either been pooled [
12] or solely the dominant follicle was examined [
13]. Information on individual fAMH concentrations within one stimulated IVF cycle is still not available, although it is tempting to speculate that individual fAMH could be a potential predictor of fertilization success in IVF treatments, since it had already been found to correlate with the respective embryo and IVF outcome, at least regarding the FF of the dominant follicle [
14]. Due to different study designs and methods used (dominant or pooled follicle analysis), it is hardly possible to compare results and draw any conclusions. Comparing all individual fAMH values with the respective embryo and IVF outcome, however, has not yet been done and would emphasize fAMH even more as potent biomarker in IVF treatment by facilitating and complementing the embryo selection process.
In this pilot study, we demonstrated that all mature follicles during a stimulated IVF cycle could be aspirated individually with the Steiner-Tan needle [
15] for fAMH analysis. We hypothesized that there was no difference between fAMH concentrations of individual follicles within one patient and that these concentrations resembled the respective sAMH value of the patient.