PCOS is the most prevalent and complex endocrine disorder affecting women of reproductive age, with sexual dysfunction and infertility among the most common complications of the condition. As much of the research around PCOS focuses on improving pregnancy outcomes, many patients are prescribed letrozole, an active aromatase inhibitor that can induce ovulation.
At the same time, however, research into sexual function in PCOS patients has been limited and often contradictory. In PCOS patients, sexual function is affected by infertility and other complications of the condition, such as androgen levels, obesity, metabolic syndrome, mental health and self-esteem.
Some studies have theorised that changes to the physiological balance of microorganisms in the intestinal microbiome is linked to the pathophysiology of PCOS. Because the absorption of probiotics, prebiotics and synbiotics contributes to intestinal microbial colony balance and intestinal pH, probiotics may help to restore this balance. Probiotics are also often used to combat reduced insulin resistance, inflammation, and oxidative stress — all factors that increase with PCOS.
Measuring function and satisfaction
With the aforementioned in mind, researchers at the Hormozgan University of Medical Sciences and Yasuj University of Medical Sciences in Iran set out to “provide scientific evidence as the first RCT” to study the impact of oral probiotics on sexual function in PCOS patients treated with letrozole.
The study involved 40 PCOS patients randomly split into two groups: in one, 20 women were given letrozole alone. In the other, the remaining 20 women were given letrozole and LactoFem, a synbiotic (probiotic plus prebiotic) formulation containing seven bacterial strains, as well as fructo-oligosaccharides.
In the probiotics plus letrozole group, each woman received a LactoFem capsule daily for a month. This was repeated in the second month, in addition to 2.5mg of letrozole daily for five days (starting from the third day of their respective menstrual cycles). In the letrozole group, each woman received the same dosage of letrozole in the second month, without LactoFem. Both groups were also prescribed folic acid throughout the study.
The study subjects then completed questionnaires after the intervention, which used the Female Sexual Function Index (FSFI) and Body Image Concern Inventory (BICI) to assess sexual function and body satisfaction, respectively.
The significance of probiotics
The researchers observed a statistically significant increase of 10% in the pregnancy rate in the probiotics plus letrozole group compared to the letrozole group. There was also a statistically significant difference in sexual function between the two groups post-intervention, with the probiotics plus letrozole group seeing a marked improvement in the FSFI domains and mean body image score, compared to the letrozole group.
Another reason for the improved fertility in the probiotics plus letrozole group was the positive impact of Lactobacillus supplements, whose reduction of inflammation in PCOS patients was said to have helped mitigate their fertility issues.
This improvement in fertility was also linked to the enhanced body image scores observed in the probiotics plus letrozole group, which was consistent with previous research conducted on the association between infertility and body dissatisfaction in women.
In terms of sexual function, the researchers wrote that PCOS caused the body “to lose control and feel useless”, leading to a negative perception of one’s own body and therefore, affecting the capacity for sexual activity. Probiotics’ effectiveness in alleviating PCOS may therefore explain the improved FSFI scores in the probiotics plus letrozole group.
Possible inconsistencies
The researchers acknowledged that because the data was self-reported, there was a possibility of incorrect reporting. Furthermore, as the study subjects were all patients at a gynaelogical clinic, there were differences in the number of socio-cultural and psychological parameters among them compared to the wider Iranian population.
There may also have been “a bias towards PCOS patients with menstrual disorders and infertility, rather than those with other PCOS-related symptoms” who often go to endocrine clinics. Moreover, for cultural reasons dictating that Muslim women must be married before trying to conceive, all the study subjects were married, and the researchers therefore advised that the study’s results be interpreted with caution.
The researchers recommend further studies with larger samples that included other ethnic groups, as well as “a well-guided RCT structure to demonstrate the potential effects related to fertility and sexual function of the probiotic supplement”.
Source: BMC Women’s Health
https://doi.org/10.1186/s12905-022-01955-z
“Probiotic effects on sexual function in women with polycystic ovary syndrome: A double-blinded randomized controlled trial”
Authors: Maryam Azizi-Kutenaee, et al.
