Letrozole: an emerging array of hope for infertile women

Abstract

Ovulation induction has been a major breakthrough in the management of female infertility since many decades. Letrozole, an aromatase inhibitor has been used as a potential therapy for ovulation induction. A large number of clinical evidences have been emerging which cite the beneficial role of Letrozole in conditions like anovulatory infertility, polycystic ovary syndrome (PCOS), unexplained infertility and an incipient role in endometriosis- related infertility with regards to higher live-birth rates. Letrozole is a superior alternative to Clomiphene citrate (CC) which has been used conventionally as ovulation inducer. Clomiphene citrate has certain well-defined disadvantages, whereas Letrozole overcomes these limitations to a reasonable extent. The peripheral anti-estrogenic effect of CC leads to prolonged depletion of estrogens receptors, adversely affecting endometrial growth and development as well as quantity and quality of cervical mucus. Persistent blockade of estrogen receptor leads to CC resistance and is associated with reduced ovulation and pregnancy rates. Available evidences suggest Letrozole is superior to CC owing to the lack of persistent anti-estrogenic action due to its short half- life and lack of action on estrogen receptors. This typically leads to monofollicular growth and also higher live birth rates. The current evidences suggest that Letrozole can be placed as first line therapy for the management of infertility due to PCOS and unexplained infertility.

Thymoquinone improves folliculogenesis, sexual hormones, gene expression of apoptotic markers and antioxidant enzymes in polycystic ovary syndrome rat model

“…It stimulates ovulation by inhibiting oestrogen secretion; the resulting hypoestrogenic state enhances GnRH release and pituitary FSH production. Thus, letrozole has a beneficial role in anovulatory infertility, PCOS and unexplained infertility (Maladkar et al., 2020 ). Thymoquinone was utilized at doses of 5 and 10 mg/kg in this investigation.…”

Poly(propylene glycol) vs Sugar Alcohol-Based Aqueous Biphasic System to Extract Drugs and Subsequent Recovery of the Polymer

“…After phase separation, the polymer-rich phase was taken for UV−vis spectral analysis. The extraction study was performed in different pH media (pHs 3, 5, and 7), and the pH of the phase-forming components was adjusted by aqueous 16 it will be interesting to study their extraction patterns in the presence of each other. Not only these two drugs, vitamin C (L-ascorbic acid) and zinc are also recommended in the treatment of COVID-19 patients.…”

“…Not only these two drugs, vitamin C (L-ascorbic acid) and zinc are also recommended in the treatment of COVID-19 patients. 16,21 For this reason, the extraction patterns of Ivermectin and Doxycycline were also checked in the presence of L-ascorbic acid and zinc acetate separately. The solo extraction behaviors of these two drugs (Ivermectin and Doxycycline) in the polymer-rich phase of the newly designed ABS suggest that the optimum pH of extraction is 7.…”

“…Not only Ivermectin and Doxycycline, but also some of the reports suggested that the use of vitamin C and zinc along with these two drugs shows a good result in the treatment of COVID-19. 16,21 For this reason, in this research, we have also studied the partition behavior of Ivermectin and Doxycycline in the presence of L-ascorbic acid (vitamin C) and zinc acetate under optimum conditions.…”