Emily Oster

8 min Read Emily Oster

Emily Oster

Better Know Your Menstrual Products

The data on pads, tampons, menstrual cups, period underwear, and more

Emily Oster

8 min Read

When I got my first period (morning after the first dance in 7th grade, which is pretty perfect), my mom provided me with some pads and, shortly after that, tampons. As in all things puberty, my mom’s approach was pretty much to just provide whatever she was using. We are all economists: this was efficient, and saved on having to stock multiple items.

This is how I ended up as the only 13-year-old in America using Ban deodorant and OB tampons. For the uninitiated, OB tampons have no applicator, which was … an experience. It was only several years later that I learned about applicator tampons and thought some version of That could have been easier.  

Thirty years ago, pads and tampons were the entire period protection game. No more. The menstrual protection landscape has changed significantly in ways that are exciting but also sometimes confusing. Are period underwear the greatest invention ever, or some kind of dangerous chemical delivery system? Is a menstrual cup awesome, or is it some kind of difficult-to-use device that might dislodge your IUD? These questions matter for us as adults, and they also matter for those of us thinking about how to advise our children. Should I be handing over OB tampons, or has that ship sailed?

Today, ParentData gives you the rundown on the menstrual technology options — what they are, whether there are concerns, and what the data says. I’m not going to take a stand on the best menstrual technology! That’s for you and your vagina to decide.

Pads

(Yes, I know you don’t need a primer, but I like to be complete.)

What are they? Absorbent plastic- or fiber-based products that stick into your underwear and collect menstrual blood.

Leakage potential? Possible. Depending on the amount of blood, the position of the pad, how you’re sitting, etc.

What are the concerns and are they grounded in anything? Menstrual pads produce a lot of waste and they can be uncomfortable. There are no significant health concerns.

Tampons

What are they? Absorbent cotton-based cylinders that are inserted in the vagina, either with an applicator or without, where they collect blood. They are changed every four to six hours.

Leakage potential? Possible. If pushed past their absorbency capacity, tampons stop collecting blood, and you’ll get leakage.

What are the concerns and are they grounded in anything? Like pads, tampons raise concerns about waste. The primary health concern with tampon usage is toxic shock syndrome (TSS), which is a serious — potentially fatal — illness caused by bacterial growth. TSS has multiple causes, but in the late 1970s it was recognized as linked with tampon use.

Though very scary, TSS is rare. There were about 5,300 cases reported between 1979 and 1996. Incidence has declined over time, likely following the removal of some super-absorbent tampons from the market. More recent studies have shown that wearing a single tampon for longer than six hours or overnight is linked with TSS, suggesting that restricting usage to shorter periods is protective.

Menstrual cup

[Author’s note: I admit to having a soft spot for the menstrual cup. Back in graduate school, I did an experiment in Nepal involving menstrual cups and schooling. I got to hand a menstrual cup around at seminars, which was a highlight of my seminar-giving career and one of my best Vagina Economist stories.]

What is this? A menstrual cup is a small, flexible silicone cup that is inserted in the vagina to collect blood. It’s removed, emptied, and reinserted about every 12 hours. A single cup can hold the volume of four normal tampons, so there’s more flexibility in timing.

These cups come in varying sizes — usually women post-childbirth need a larger size and teen girls need a smaller size. There are a variety of companies producing them,. including Diva and Saalt.

Leakage potential? Possible, but studies suggest perhaps lower than pads or tampons. These studies are not large or especially well-designed, so I wouldn’t hang too much on them, but the situation certainly doesn’t look worse. It’s worth saying that when you take out a menstrual cup, you do need to empty it, and spillage can occur.

What are the concerns and are they grounded in anything? With menstrual cups, there is a learning curve in usage. To insert the cup, you have to fold it correctly (in fourths) and then allow it to open once in the vagina. It’s not complicated once you figure it out, but it takes a few tries. (My second menstrual cup research paper was about how girls were more likely to use the cups if their friends also had them, suggesting you can also learn from others.)

A meta-analysis of studies about menstrual cups — in both developing and developed countries — finds they are generally safe and well-tolerated. They aren’t associated with infection or change in vaginal flora, or with injury. A particular concern that is sometimes raised is the possibility that when the cup is removed, it might dislodge an IUD. This possibility was raised after a small number of case reports. However: a larger study suggested no systematic difference in the risk of IUD expulsion for use of menstrual cups versus other forms of protection. My read of the data is that this isn’t a significant concern.

There are also, it should be noted, some important advantages relative to tampons. The risk of TSS is lower, and they can be used for longer. They are reusable, meaning they do not produce as much waste, and the overall cost is considerably lower if you amortize over the life of the cup.

Period underwear 

What is this? They’re underwear; they look like normal underwear, but they absorb menstrual blood. You wash them and reuse. Most of the products in this space (Thinx, Saalt) advertise the collection of four to five tampons’ worth of blood. The idea is you’d wear them all day or overnight without a need to change. These come in a variety of styles, from boyshorts to thongs (the thongs have less absorbency.)

Wirecutter, which is often my go-to for product advice, has a large set of reviews that are worth reading if you’re looking in this space and want to know, for example, which of them are “period-sex-worthy.”

Leakage potential? These can fill and leak (see Wirecutter for details), more so with smaller pairs. User data is encouraging, but I was unable to find any peer-reviewed studies that discussed relative leakage.

What are the concerns and are they grounded in anything? There was a concern raised about PFAS chemicals in period underwear. These chemicals are used in many manufacturing processes, and there are concerns that they are endocrine-disrupting. As I’ve written about before, the data on the risks of PFAS chemicals is not ironclad or especially well-understood. Most manufacturers of these products have committed to eliminating or limiting their presence in these products. Combining these things — and reflecting on all of the other PFAS exposures in our lives — it doesn’t seem like a data-supported reason to avoid these.

Advantages here: reusable, do not produce waste (although they do need to be laundered), easy to use. These products are expensive, although, like the cup, on an amortized basis they seem like a better deal.

Final note: Do I need my period? 

Women’s bodies have evolved to cycle regularly every 21 to 35 days. A monthly period is a sign that our hormonal system is functioning normally. Outside of pregnancy, breastfeeding, and hormonal contraception use, irregular or absent periods are often a symptom of a health problem. Over time, absent periods can contribute to an increased risk for osteoporosis and endometrial cancer. If your periods are not regular, your doctor can do blood work and other tests to figure out why.

However, hormonal contraceptives, including birth control pills, patches, and rings; progestin-releasing IUDs — Mirena and Kyleena are two brands — Depo-Provera injections; and contraceptive implants like Nexplanon can all change how often women have bleeding and how much bleeding they have. It is completely safe to skip periods or to not have a period at all while using these types of contraceptives. And in fact, for women with certain medical problems, like anemia or endometriosis, not having periods or having them less frequently can be beneficial.

For at least some of us, this is worth adding to our option list. And whatever you decide: have a happy period!

Thanks to endocrinologist Dr. Gillian Goddard for weighing in on the last part; check out her owner’s manual for breasts.

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Do you brand things a certain way to get your kid to accept it? Like calling carrots “rabbit popsicles”? Or telling them to put on their “super speed socks” in the morning? Share your rebrands in the comments below! You never know who you might be helping out 👇

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Do you brand things a certain way to get your kid to accept it? Like calling carrots “rabbit popsicles”? Or telling them to put on their “super speed socks” in the morning? Share your rebrands in the comments below! You never know who you might be helping out 👇

#emilyoster #funnytweets #relatabletweets #parentingjokes #kidssaythedarndestthings
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Have you ever panic-googled a parenting question when everyone else is asleep? If so, you’re not alone.

Today is the first episode of a new biweekly series on my podcast: Late-Night Panic Google. On these mini-episodes, you’ll hear from some familiar names about the questions keeping them up at night, and how data can help. First up: @claireholt!

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#parentdata #emilyoster #claireholt #parentingstruggles #parentingtips #latenightpanicgoogle
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Sun safety is a must for all ages, especially babies! Here are my tips for keeping your littlest ones protected in the sunshine:
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Sun safety is a must for all ages, especially babies! Here are my tips for keeping your littlest ones protected in the sunshine:
☀️ Most importantly, limit their time out in hot weather. (They get hotter than you do!)
☀️ Keep them in the shade as much as possible when you’re out.
☀️ Long-sleeve but lightweight clothing is your friend, especially on the beach, where even in the shade you can get sunlight reflecting off different surfaces.
☀️ If you want to add a little sunscreen on their hands and feet? Go for it! But be mindful as baby skin tends to more prone to irritation.

Comment “Link” for a DM to an article on the data around sun and heat exposure for babies.

#sunsafety #babysunscreen #babyhealth #parentdata #emilyoster
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I’m calling on you today to share your story. I know that many of you have experienced complications during pregnancy, birth, or postpartum. It’s not something we want to talk about, but it’s important that we do. Not just for awareness, but to help people going through it feel a little less alone.

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OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio! ...

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio!

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio! ...

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio!

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio! ...

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Sources:
📖 #ExpectingBetter pp. 160-163
📈 Robert M. Silver et al., “Prospective Evaluation of Maternal Sleep Position Through 30 Weeks of Gestation and Adverse Pregnancy Outcomes,” Obstetrics and Gynecology 134, no. 4 (2019): 667–76. 

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Is side sleeping important during pregnancy? Comment “Link” for a DM to an article on whether sleep position affects pregnancy outcomes.

Being pregnant makes you tired, and as time goes by, it gets increasingly hard to get comfortable. You were probably instructed to sleep on your side and not your back, but it turns out that advice is not based on very good data.

We now have much better data on this, and the bulk of the evidence seems to reject the link between sleep position and stillbirth or other negative outcomes. So go ahead and get some sleep however you are most comfortable. 💤

Sources:
📖 #ExpectingBetter pp. 160-163
📈 Robert M. Silver et al., “Prospective Evaluation of Maternal Sleep Position Through 30 Weeks of Gestation and Adverse Pregnancy Outcomes,” Obstetrics and Gynecology 134, no. 4 (2019): 667–76.

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My new book, “The Unexpected: Navigating Pregnancy During and After Complications” is available for preorder at the link in my bio!

I co-wrote #TheUnexpected with my friend and maternal fetal medicine specialist, Dr. Nathan Fox. The unfortunate reality is that about half of pregnancies include complications such as preeclampsia, miscarriage, preterm birth, and postpartum depression. Because these are things not talked about enough, it can not only be an isolating experience, but it can also make treatment harder to access.

The book lays out the data on recurrence and delves into treatment options shown to lower risk for these conditions in subsequent pregnancies. It also guides you through how to have productive conversations and make shared decisions with your doctor. I hope none of you need this book, but if you do, it’ll be here for you 💛

#pregnancy #pregnancycomplications #pregnancyjourney #preeclampsiaawareness #postpartumjourney #emilyoster
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Only two weeks until our book “The Unexpected” is here! Preorder at the link in my bio. 💙
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Exciting news! We have new, high-quality data that says it’s safe to take Tylenol during pregnancy and there is no link between Tylenol exposure and neurodevelopmental issues in kids. Comment “Link” for a DM to an article exploring this groundbreaking study.

While doctors have long said Tylenol was safe, confusing studies, panic headlines, and even a lawsuit have continually stoked fears in parents. As a result, many pregnant women have chosen not to take it, even if it would help them.

This is why good data is so important! When we can trust the data, we can trust our choices. And this study shows there is no blame to be placed on pregnant women here. So if you have a migraine or fever, please take your Tylenol.

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...

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For this graph, researchers used a standardized measure of vocabulary size. Parents were given a survey and checked off all the words and sentences they have heard their child say.

They found that the average child—the 50th percentile line—at 24 months has about 300 words. A child at the 10th percentile—near the bottom of the distribution—has only about 50 words. On the other end, a child at the 90th percentile has close to 600 words. One main takeaway from these graphs is the explosion of language after fourteen or sixteen months. 

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How many words should kids say — and when? Comment “Link” for a DM to an article about language development!

For this graph, researchers used a standardized measure of vocabulary size. Parents were given a survey and checked off all the words and sentences they have heard their child say.

They found that the average child—the 50th percentile line—at 24 months has about 300 words. A child at the 10th percentile—near the bottom of the distribution—has only about 50 words. On the other end, a child at the 90th percentile has close to 600 words. One main takeaway from these graphs is the explosion of language after fourteen or sixteen months.

What’s valuable about this data is it can give us something beyond a general guideline about when to consider early intervention, and also provide reassurance that there is a significant range in this distribution at all young ages.

#cribsheet #emilyoster #parentdata #languagedevelopment #firstwords
...