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What Does Your Baby Feel When You Laugh During Pregnancy? Health & Happiness Really Are Connected

Many pregnant women know intuitively that their baby absorbs their emotions like a little fetal sponge. Personally, I'll never forget the time I went to see a horror movie with my partner a month before my due date (in retrospect, a mistake). She actually jumped at the jump scares. Later, I reflected on how the adrenaline rushing through me must also have affected her, and resolved to watch only movies that made me laugh. But what does your baby feel when you laugh during pregnancy? There are many reasons to laugh uproariously whenever you possibly can.

Physically, when you laugh, your baby bounces up and down on a kind of uterine trampoline, reported Family Share — I assume this is why bouncy castles are so popular at birthday parties. But as it turns out, there's a lot more to pregnancy joy than you might think. Dr. Camille Hoffman, a Maternal-Fetal Medicine provider at Saint Joseph Hospital in Denver, Colorado researching prenatal mental health, tells Romper that mothers with a more positive affect — less anxiety, more joy — later have babies with lower anxiety levels and an increased ability to cope with stress. In fact, excessive prenatal stress can even shape a child's temperament later in life, according to a study in Development and Psychopathology, and might make children more prone to depression.

"We all have stressors in our lives, but resiliency and ability to cope with stress is improved" when mom's mood is better during those crucial nine months, Hoffman explains. One measure of how you're handling stress is heart-rate variability, or HRV. According to Harvard Health, "HRV is simply a measure of the variation in time between each heartbeat," which in turn indicates overall nervous system function and balance.

When you're stressed, Hoffman explains, your heart rate is fast and unchanging. But when you chill out, the heart beat is more flexible, or variable. People who meditate or have mindfulness practices tend to have excellent HRV, and when depressed people start feeling better, you can read the change in their heartbeat.

Unlike with cortisol tests, HRV tests provide a quick picture of a pregnant woman's wellbeing in real time, making it a great measure for researchers. Hoffman's group uses a heart-rate variability biofeedback device for moms and babies, and during ultrasounds, the findings are fascinating: when mom is looking at her baby onscreen, HRV improves. In other words, when mom is reassured and content, she gets healthier right away. "You can see that change reflected immediately in her autonomic nervous system function," says Hoffman.

Because mom's nervous system is so intimately bound up with her baby's, her happiness is good news for both of them. According to the March of Dimes, consistent stress can even increase your risk of giving birth prematurely.

But let's pause for a second. When I was pregnant, reading about how stress is terrible for your baby almost always gave me a mini panic attack — and stressing about feeling stressed is a vicious, useless cycle. What's great about the work that Hoffman and her team is doing is that they're not just warning mothers to avoid feeling anxious — I mean, we all have jobs and spouses and lives, right? Instead, she's looking at breathing practices and a pregnancy meditation app called Expectful, and these are practical measures any pregnant woman can take to feel better.

If you're not into yoga, however, I'd suggest tacking an ultrasound picture to your refrigerator or carrying one in your wallet for a quick hit of happiness. Also, consider Netflix-ing a comedy tonight. As the old saying goes, laughter is the best medicine.

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