Data show slight increase in menstrual length after COVID vaccines

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vaccine women
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Investigators analyzing data on almost 2 million women participating in 17 studies observed a slight and transient increase in the length of menstruation after they received a COVID-19 vaccine, according to a study published late last week in PLOS One.

The authors said the study offers clarity on the topic. "Given the extensive reporting by the media on the topic, a continued lack of clarity can fuel further vaccine hesitancy, not just for COVID-19 vaccines but also more broadly with serious implication," they wrote. 

Overall, women who received a COVID vaccine had a 19% greater risk of increase in menstrual cycle length as compared to unvaccinated women or women in pre-vaccination time periods (summary relative risk [sRR], 1.19; 95% confidence interval [CI], 1.11 to 1.26). 

Changes observed in only 1 cycle

Both the Moderna and Pfizer mRNA vaccines carried the same 15% increased risk of an extended menstrual cycle. AstraZeneca and Johnson & Johnson had higher risks (sRR, 1.27 and 1.69, respectively).

After the first vaccine dose, menstrual cycle length increased an average of less than half of one day, and after the second dose 0.62 days. All changes were observed only in the first cycle after vaccination, and menstrual length returned to normal in the second cycle. 

The fear of menstrual disturbance should not discourage anyone from getting COVID-19 vaccine.

"Results of this study show that there exists but a minimal and short-lasting risk of increased menstrual disturbance associated with COVID-19 vaccines that could likely be experienced by females as a normal variant sometime during a 12-month time-frame regardless of vaccination," the authors concluded. "The fear of menstrual disturbance should not discourage anyone from getting COVID-19 vaccine."

WHA begins with Pandemic Agreement up for final vote

News brief

The World Health Assembly (WHA) began its 9-day meeting in Geneva today, with the highlight expected to be a final vote on the Pandemic Agreement, a proposal developed over the past 3 years with complex negotiations led by the Intergovernmental Negotiating Body (INB).

WHO logo on window
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The WHA, made up of representatives from member countries, is the main decision-making body of the World Health Organization (WHO). 

In the wake of missteps and major preparedness gaps laid bare during the height of the COVID-19 pandemic, WHO member states established the Intergovernmental Negotiating Body (INB) to draft and negotiate a pandemic accord with a goal of strengthening global collaboration to help prevent, prepare for, and respond to future pandemic threats. Before the draft was finalized in the middle of April, it took 13 rounds of formal meetings and many other informal sessions to smooth out different elements of the agreement.

The measure was approved today in committee A, with 124 countries voting in favor, 0 against, and 11 abstaining. In a post on X , WHO Director-General Tedros Adhanom Ghebreyesus, PhD, called it a “truly historic evening.” The final step is a vote in tomorrow’s plenary session.

Pared back budget another key issue

Another key issue for the meeting is sustainable WHO funding amid cuts in funding. Member states will consider a scheduled 20% increase in assessed contributions toward the 2026-2027 budget, which reprioritizes activities amid financial challenges, which include a reduction of 22% to $4.267 billion, down from $5.3 billion in the original budget. Tomorrow the group will hold a high-level pledging event where countries and philanthropic groups are expected to announce their WHO funding.

Other key topics on the agenda include the health and care workforce, antimicrobial resistance, health emergencies, preparedness, polio, climate change, and social connection as determinants of health, among other issues.  

Better outcomes found in hospitalized pneumonia patients treated with azithromycin

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An observational study of hospitalized patients with community-acquired pneumonia (CAP) found that azithromycin was associated with lower mortality and more hospital-free days compared with doxycycline in combination with beta-lactams, Mayo Clinic researchers reported late last week in Clinical Infectious Diseases.

With macrolide resistance rising, doxycycline in combination with beta-lactams has become a frequently used alternative treatment for hospitalized CAP patients, but data on its effectiveness are limited. To compare outcomes in CAP patients who received both regimens, the researchers examined data on patients hospitalized with CAP at Mayo Clinic hospitals from May 2018 through September 2022. Patients who received either azithromycin or doxycycline in combination with beta-lactams were matched 1:1 according to the presence of congestive heart failure, coronary artery disease, chronic obstructive pulmonary disease, HIV infection, recent immunosuppressant use, and pneumonia severity index class. 

The primary outcome was in-hospital and 30- and 90-day mortality. The secondary outcome was hospital-free days.

Potential benefit in using azithromycin for CAP treatment

Among 8,492 patients eligible for the study (5,810 in the azithromycin group and 2,682 in the doxycycline group), 2,671 patients treated with doxycycline were matched with 2,671 azithromycin-treated patients. In-hospital mortality was 29% lower in the azithromycin group than in the doxycycline group (odds ratio, 0.71; 95% confidence interval [CI], 0.56 to 0.90), and 30-day mortality (hazard ratio [HR], 0.85; 95% CI, 0.72 to 0.99) and 90-day mortality (HR, 0.83; 95% CI, 0.73 to 0.95) was also reduced, by 15% and 17%, respectively. 

Azithromycin-treated patients also had significantly more hospital-free days than those treated with doxycycline-based regimens (adjusted estimated difference, 1.37 days; 95% CI, 0.99 to 1.74).

"Given that we found a difference in clinical outcomes between azithromycin versus doxycycline with beta-lactam therapy, our observational study suggests a potential benefit with using azithromycin for CAP treatment in contrast to the limited evidence available," the study authors wrote. "Randomized controlled trials are needed to assess the effectiveness of each regimen and to compare their potential side effects."

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