Blood actually is thicker than water – but makers of menstrual products have historically used saline to estimate how a lot liquid they will maintain.
The capability to soak up of conventional menstrual products is a standard strategy to measure the quantity of blood misplaced. Clinicians use it to diagnose heavy menstrual bleeding, which impacts roughly a 3rd of menstruating people worldwide (from 18.2% in China to 37.9% in Turkey) and might be an indication of extra worrying illnesses, reminiscent of fibroids.
But prognosis is difficult when people use non-traditional products like discs and cups and when products’ marketed skills are imprecise.
‘No data with blood’
Now, researchers from the Oregon Health & Science University (OHSU) have reported, in a examine revealed in the journal BMJ Sexual & Reproductive Health on August 7, the absorbency of each conventional and non-traditional interval products utilizing not saline or different fluids however with human blood.
They discovered the marketed capacities of many products to be deceptive.
Supriya Kamath, an MS in obstetrics and gynaecology from Mumbai’s Okay.E.M. Hospital whose residency begins in November, famous the significance of utilizing blood to test menstrual products, “since it is blood and not urine which has to be absorbed”. (Saline is akin to urine.)
Bethany Samuelson Bannow, a coauthor of the revealed paper and an assistant professor of drugs at OHSU, mentioned the rising fraction of their affected person inhabitants utilizing menstrual cups motivated her group to evaluate the absorbency of non-traditional products as nicely.
“We decided to pursue information around how much alternative period products absorb,” Dr. Bannow advised this author in an e mail. “While reviewing testing methods for disposable products, [we] realised that there are no data on maximum absorption of these products with blood.”
From underwear to discs
Her group used packed pink blood cells (RBCs) separated from entire blood to evaluate the capability of 21 widespread products, together with discs, cups, tampons, sanitary pads, and underwear. The manufacturers they selected are commercially accessible in the U.S. and Europe; some can be found on-line in India.
For their assessments, the group selected pads of two manufacturers with completely different reported absorbencies, tampons from one model, and three pairs of interval underwear with the identical reported absorbency. They additionally examined menstrual cups of various sizes from one model and discs of two sizes from completely different manufacturers.
To measure the absorbency of pads and interval underwear, the group poured RBCs over the central higher third till the RBCs pooled under or the product stopped absorbing them.
To assess the capability of tampons, the researchers positioned every tampon in a cup with 50 ml of RBCs for half-hour or till the blood reached the wick, and recorded how a lot the tampon had absorbed. They additionally stuffed cups and discs with RBCs to the brim and measured the quantity.
They discovered that menstrual underwear products, no matter dimension, soaked the least quantity of blood – solely 2 ml on common, which Dr. Bannow mentioned was stunning. Menstrual discs held the most: 61 ml on common, with one model holding about 80 ml. Tampons, sanitary pads, and menstrual cups held 20-50 ml.
What is heavy bleeding?
To Dr. Bannow, the principal conclusion was that menstrual cups and discs can maintain a considerable amount of blood. So individuals who saturate or fill these products a number of occasions per cycle are more likely to have heavy menstrual bleeding.
“The bottomline is we want every person who menstruates to know whether their periods are truly ‘normal,’ and to have access to evaluations and treatments if their periods are heavy.”
The researchers additionally discovered their measurements to disagree with ads.
“We were not terribly surprised that pads and tampons absorbed more blood than saline,” mentioned Dr. Bannow, including that this had been reported however not revealed earlier than. While a product holding extra blood might be interpreted as an excellent factor, the elevated absorbency might cover heavy bleeding.
“Being aware of what’s normal and what’s heavy is important since heavy menstrual bleeding can cause health complications,” Dr. Kamath mentioned.
“The viscosities and composition of blood and water are very different and we can’t expect a product to have similar holding capacities for the two liquids,” mentioned Ananya Petkar, an unbiased gynaecologist. “This study is a great attempt to check the absorbing capacity of different products.”
The authors, together with Dr. Bannow, acknowledged of their paper that whereas RBCs are extra viscous than saline, they’re nonetheless not an ideal proxy for menstrual blood, which additionally contains endometrial cells and vaginal secretions. The consistency of menstrual blood additionally differs between people and on completely different days.
Dr. Bannow & co. are actually learning menstrual cups and interval underwear in people with heavy menstrual bleeding.
Too little analysis on menstruation
Dr. Petker additionally famous that the researchers measured the quantity of blood that products might maintain by filling every merchandise. But in actuality, ladies might not wait till a pad is totally soaked or a cup stuffed to alter it. This additionally creates variance between the examine’s findings and the products’ precise use and their medical implications.
Another limitation of the software of this examine in India, in response to each Dr. Kamath and Dr. Petkar, is that not all products examined are simply as accessible in India as they’re elsewhere. Dr. Kamath singled out cups and discs for their comparatively decrease use in India as a result of that requires “practice and a little knowledge of the female anatomy”.
“If we know the correct method to measure blood loss, only then can we educate others and catch and treat heavy menstrual bleeding,” Dr. Kamath mentioned. “To do so, we need more research on this topic.”
Research on menstruation stays restricted. A 2020 assessment discovered 400 papers in 2011-2018 mentioning “menstrual blood” in the PubMed database whereas greater than 10,000 talked about semen.
“I think people in general need to feel more comfortable discussing periods,” mentioned Dr. Bannow. She expressed delight at the consideration her current examine has acquired. It “is pushing a discussion around menstruation to the forefront.”
Sneha Khedkar is a biologist-turned freelance science journalist primarily based out of Bengaluru.
