The goal of this randomized placebo-controlled study is to investigate the short-term effects of transdermal estrogen therapy on postmenopausal women with COVID-19 disease.

The main question[s] it aims to answer are:

• the clinical outcomes with adding estrogen treatment to conventional therapy of Covid-19 disease
• the biochemical outcomes with adding estrogen treatment to conventional therapy of Covid-19 disease

All participants received favipiravir for a week according to the national guidelines published by the Health Ministry of Turkish Republic at that time.

As an intervention, transdermal estradiol patch (7.8 mg patch/week) was applied for 14 days on the upper buttock of the patients in experimental arm. As a placebo, hydrogel patch (adhesive hydrogel patch/week) was applied to the female patients for 14 days.

Researchers compared experimental and control groups to see if the impact of adding estrogen on the clinical course of Covid-19 disease

The risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, morbidity and mortality from Covid-19 disease were higher among men compared to women. This is caused by the differences in immunological response and viral pathogenesis between men and women. It is theoretically assumed that estrogen has a positive impact on female COVID-19 patients. In this randomized placebo-controlled study, we aimed to investigate the short-term effects of transdermal estrogen therapy on postmenopausal women with COVID-19 disease. Female patients diagnosed with Covid-19 disease were examined and only postmenopausal women were included into the study. The COVID-19 diagnosis was made with a positive reverse transcription-polymerase chain reaction (RT-PCR) test given with nasal and oral swabs. All participants received favipiravir for a week according to the national guidelines published by the Health Ministry of Turkish Republic at that time.

As an intervention, transdermal estradiol patch (7.8 mg patch/week) was applied for 14 days on the upper buttock of the patients in experimental arm. As a placebo, hydrogel patch (adhesive hydrogel patch/week) was applied to the female patients for 14 days.

Our primary outcome was to achieve better clinical and biochemical outcomes with adding estrogen treatment to conventional therapy of Covid-19 disease. The epidemiological and clinical data, the results of biochemical analysis, the information regarding the treatment and outcomes and serum estradiol levels were determined.

Inclusion Criteria:

• Female patients diagnosed with Covid-19 disease
• Postmenopausal women (who had 12 months of amenorrhea after their final menstrual period)
• Positive reverse transcription-polymerase chain reaction (RT-PCR) test given with nasal and oral swabs

Exclusion Criteria:

• Negative RT-PCR test
• Female patients at reproductive stage