Curb walking, GBS, and acid reflux

Welcome to the weekly ZIP - your Zenith Informed Pregnancy!

Read on for a quick zip through 3 of the week’s most popular pregnancy questions, and the evidence behind them. Plus - bonus content on the latest & greatest in the world of pregnancy research. 

This week's top pregnancy questions:

1️⃣ Does curb walking actually work to induce labor?

2️⃣ How much acid reflux is normal? What can help?

3️⃣ What’s GBS? How would it affect the labor process?

Does curb walking actually work to induce labor?

What does “curb walking” even mean and why do you start hearing about it all of the sudden at the end of pregnancy? It does, indeed, mean walking with one foot on the curb and one foot on the road - and some say it can help to naturally induce labor. Is there any evidence behind this common practice?

📚The tl;dr from the evidence:  The idea is that walking while having one foot elevated up on the curb and the other on the street can create a “jostling” motion in your pelvis, moving the baby to settle lower down and put more pressure on the cervix - but so far there is no research that supports curb walking as a reliable way to start labor. 

You can certainly try it if you want to, as it’s unlikely to be harmful – the main risk/downside consideration is tripping or falling, since your balance is already altered and you’re walking on an uneven surface (with potentially close proximity to traffic, depending on your neighborhood).  

But! There is some evidence on, well, regular walking! Research shows that regular gentle movement, like walking, in low risk pregnancies at term may be associated with outcomes like more spontaneous labor – and in some trials, less need for induction. Of course, walking isn’t a guaranteed trigger for labor, just as curb walking isn’t going to magically jumpstart labor – but is a safer, more comfortable, and beneficial (in many ways!) way to get some movement and fresh air in during the final weeks and days of pregnancy.

👀 Read Penny’s full summary of the evidence for more on curb walking

How much acid reflux is normal? What can help?

Often starting seemingly out of nowhere in the second trimester, many moms are asking how much acid reflux can possibly be normal - and more importantly, what can actually help. While there’s no magic cure, here’s what the research shows about why it’s happening and what the most effective approaches to managing it are.

📚The tl;dr from the evidence:  Unfortunately, acid reflux is a very common, very unpleasant but often normal pregnancy symptom - with up to 80% of women experiencing it. It often starts during the second trimester, and becomes more likely and more prevalent the farther along you get. 

There are two pregnancy-related reasons it can happen so much: one is that hormones can cause the “valve” at the top of your stomach to relax, causing stomach contents to come back up more easily, and the other is simply physics - as the uterus grows, pressure inside your abdomen increases and can make it easier for your stomach contents to move upwards.

What actually helps? Adjustments like smaller & more frequent meals, staying upright after eating, and/or reducing spicy/greasy/acidic foods are often recommended first. If those habit changes aren’t helping, calcium-containing antacids (like Tums) are the first medication suggested and can help. For more severe (or very persistent) acid reflux, other medicines like famotidine or omeprazole haven’t shown evidence of adverse outcomes for babies when taken during pregnancy – your doctor can help you with a plan and a dose, if going beyond over the counter antacids. 

And the good news? Especially for those with no history of pre-pregnancy reflux symptoms, it usually goes away and women see a noticeable improvement soon after delivery. 

👀 Read Penny’s full summary of the evidence for more on acid reflux

What’s GBS? How would it affect the labor process?

Group B Strep, or GBS, can sound scary - and while important to screen for during pregnancy, there are well-established, evidence-backed approaches to managing what happens if you have it. Read on for why it’s important in pregnancy, how it’s screened for, and what happens in labor if you’re positive. 

📚The tl;dr from the evidence: GBS is a common type of  bacteria (about 1 in 4 pregnant people carry it), which is often asymptomatic in adults - so you may have it and never otherwise know. It becomes important in pregnancy because it can be passed to the baby in childbirth, and if untreated, a very small percentage of exposed babies can develop a serious infection during the first week of life - like pneumonia, sepsis, or meningitis. 

Screening is super important, because for moms who are GBS positive, IV antibiotics given during labor are a highly effective way to reduce your baby’s risk of early-onset GBS infection. Starting these antibiotics earlier during labor is preferred; research shows 4+ hours prior to birth is most effective, but even starting 2 hours before birth can still be effective in reducing GBS levels and lowering the odds of infection for your baby.

The actual screening process is done using a swab towards the end of pregnancy, around weeks 36-37, as knowing your status close to delivery is important in determining whether antibiotics will be needed during labor. Even if you were screened and negative in a prior pregnancy, it’s recommended to be screened again, as it can come and go in the body. 

👀 Read Penny’s full summary of the evidence for more on Group B Strep

🤓 Zenith's top read of the week

Bonus: what the Zenith team found interesting this week. Think cool pregnancy research or recently published studies, news in pregnancy health and policy, and more!

Activity Restriction in Pregnancy and the Risk of Early Delivery (Anthony Sciscione, et al, Obstetrics & Gynecology) - If you’ve ever asked yourself why certain things are recommended during pregnancy even when there’s no evidence that they’re helpful, you’ve found yourself in a similar mindset to these researchers who just published in Obstetrics and Gynecology - ACOG’s journal publication - about activity restriction (aka, bedrest) during pregnancy. While commonly prescribed, bedrest in many cases has meaningful adverse effects associated with it - so the researchers set out to see the impact of bedrest on preterm birth for women already at risk. 

They looked at preterm birth outcomes and activity restriction (or “sedentary activity” - less than 3,500 steps per day) for moms with short cervical length – one of the strongest predictive factors for preterm birth – and found that sedentary activity was associated with an increased risk of preterm birth before 34 weeks, and delivery at an earlier gestational age. 

So as it turns out… what should be an unsurprising conclusion, using practices that are not based in evidence did not result in better outcomes for moms and babies. Let’s hope that results from papers like this continue to build, and more importantly, are disseminated and effectively integrated into clinical practice so that we stop seeing such a disconnect between what we know from the data and what’s happening to moms in the real world!

Key excerpt:

“Despite numerous studies showing the adverse effects of this practice (including bone loss, thromboembolism, physical deconditioning, and significant negative psychiatric effects), the lack of evidence supporting its benefit, and the recommendations against its use by professional societies, it has continued to be used. … 80–95% of obstetric practitioners use activity restriction in their practice, and between 14% and 18% of pregnant patients are placed on activity restriction at some point during their pregnancy.”