Accessibility of immunomodulators and PRP growth factors to reproductive tissues is more limited than commonly assumed. If these therapies act predominantly through systemic immune modulation (e.g., Fc receptor saturation, Th1/Th2 modulation), direct tissue penetration may not be necessary. For PRP, observed effects likely result from indirect mechanisms (paracrine signaling, angiogenesis). Distinguishing between systemic and local mechanisms is essential. Until pharmacokinetic studies quantify drug concentrations in reproductive tissues, clinical use should remain cautious.
Celik et al. (Wed,) studied this question.