 Corresponding author: Faith Ayobamidele, OBAFEMI Copyright © 2023 Author(s) retain the copyright of this article. This article is published under the terms of the Creative Commons Attribution Liscense 4.0. A review of the effect of fertility agents (Herbs and drugs) on the hypothalamus Grace UMAHI-OTTAH and Faith Ayobamidele OBAFEMI * Department of Physiology, Faculty of Basic Medical Sciences, Ebonyi State University, Abakaliki, Nigeria. World Journal of Advanced Research and Reviews, 2023, 19(03), 705–718 Publication history: Received on 05 August 2023; revised on 12 September 2023; accepted on 14 September 2023 Article DOI: https://doi.org/10.30574/wjarr.2023.19.3.1881 Abstract The hypothalamus plays a central role in regulating fertility through its interactions with the hypothalamic-pituitary- gonadal (HPG) axis. This review provides a comprehensive analysis of the effects of fertility agents, including herbs and pharmaceutical drugs, on the hypothalamus and its role in fertility regulation. The hypothalamus directly influences the HPG axis by secreting GnRH, a hormone crucial for sexual development and ovulatory cycles. GnRH can be secreted in pulsatile or surge modes, with distinct implications for reproductive function. The HPG axis further regulates reproductive organs and hormonal production, affecting processes like oocyte maturation, ovulation, and steroid hormone synthesis. Herbal remedies have been used historically in various cultures to address fertility issues. Several plants, such as Withania somnifera, Punica granatum, Camellia sinensis, Matricaria chamomilla, Vitex agnus-castus, and Nigella sativa, have been studied for their potential to enhance fertility by modulating the HPG axis and influencing sex hormone levels. Pharmaceutical fertility drugs like clomiphene citrate and metformin also have a significant impact on the hypothalamus. Clomiphene citrate acts as a partial estrogen agonist in the hypothalamus, leading to increased gonadotropin-releasing hormone (GnRH) production and subsequent elevation of gonadotropin levels. Metformin, primarily used for diabetes management, can restore ovarian function in women with polycystic ovary syndrome (PCOS) and improve pregnancy outcomes. Understanding the intricate interactions between fertility agents and the hypothalamus is crucial for developing effective treatments for infertility and optimizing reproductive health. Keywords: Hypothalamus; Fertility Agents; Fertility Treatments; Hormones; Infertility 1. Introduction According to the World Health Organization (WHO, 2023) the inability to conceive, carry a pregnancy to term, or infertility is a disease of the reproductive system marked by the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual interaction. It's still a sizable problem on a global scale. The difficulties brought on by infertility are numerous and are frequently attributed to a multifaceted issue in Sub-Saharan Africa such as unsafe abortions, sexual transmitted diseases and postpartum infections (Gerrits & Shaw, 2010). The prevalence of problems with reproductive health is rising in this area (Larsen, 2000). One major hurdle is accurately determining the prevalence of infertility. This challenge arises due to several factors. Firstly, there is diversity in how infertility is described or defined, leading to variations in what is considered infertility (WHO, 2023; Gurunath et al., 2011). Secondly, the estimates of infertility can differ based on the size of the population and the scope of coverage, whether derived from population surveys or epidemiological studies, and this discrepancy exists in low, middle, and high-income countries (Polis et al., 2017). Lastly, determining the direct causal factors or who is responsible for infertility, whether it's males, females, or couples, adds another layer of complexity to estimating its prevalence (Gurunath et al., 2011).