5 Weeks Pregnant: Symptoms & Baby Development - Babylist
5 Weeks Pregnant
September 7, 2021

5 Weeks Pregnant

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5 Weeks Pregnant.
5 Weeks Pregnant

How Big is Your Baby at 5 Weeks?

Your baby is 0.09 inches long this week. That’s about the size of a Pop Rocks crystal.

Here’s what else to know when you’re 5 weeks pregnant:

Your Baby’s Development at 5 Weeks

If you were to have a 5 week ultrasound, your baby wouldn’t look very recognizable to the human eye. By week 5 of pregnancy, the embryo is about the size of rice seed, and looks more like a tiny tadpole than a human, says Dr. Kim Langdon, MD, OBGYN. But development is starting to ramp up.

  • Organ development: It might seem early, but your baby is starting to develop major organs like the heart, stomach, liver and kidneys.
  • Simple beginnings: Right now, your baby consists of three germ layers (weird but the technical term). The ectoderm will become your baby’s brain, spinal cord, skin and nails. The mesoderm will be the heart and circulatory system, and the endoderm will be the lungs, intestines and other major organs. “One of the first noticeable organs to work is the heart,” adds Dr. Langdon. Human development is crazy!

5 Weeks Pregnant Ultrasound


Top Tip for 5 Weeks Pregnant

Go with your gut—share your pregnancy news when you feel it’s right. More and more people are opting to tell a few close friends as soon as they find out they’re pregnant rather than obeying a “12-week rule.” If you’re excited, there’s a good chance your friends and family will be too.

Your Body: 5 Weeks Pregnant Symptoms

How’d you first know you were pregnant? Some people realize they’re dead tired at 7 pm. Others weep openly while watching a TV commercial. According to a survey, though, the the most common first signs of pregnancy people reported were missing their period, nausea and a change in their breasts (either soreness or darker areolas). “Morning sickness and fatigue, breast tenderness are among the most common symptoms of early pregnancy,” says Dr. Langdon. So, if you’re experiencing any of those, you’re definitely not alone.

Here are some other things you may be experiencing at 5 weeks pregnant.

  • Rising hCG levels: At-home pregnancy tests are pretty reliable after the first day of your missed period. They measure the level of the pregnancy hormone human chorionic gonadotropin (hCG), which is doubling every day.
  • Sore boobs: Those hormones are kicking into high gear to get your uterus started on making a baby, and this can cause really tender breasts.
  • Mood swings: The ups and downs tend to be most intense during the first trimester and postpartum, as hormone levels undergo big changes. Be gentle on yourself—eating right and getting enough rest can help—and remember that this pregnancy symptom will pass.
  • No symptoms: If you’re 5 weeks pregnant with no symptoms, there’s a chance nausea and fatigue will hit over the next few weeks. But there are also some parents-to-be who never get morning sickness at all. It all depends on your body; some people have no real symptoms beyond a growing belly the entire pregnancy.

How to Count Your Pregnancy Weeks


You might have been surprised when you found out you were pregnant, that you were already four or five weeks along. That flew by!

How did you skip the first month? Well, it’s hard to know exactly when a baby is conceived, but due dates are essential for understanding and studying pregnancy. Health professionals need a standard, so pregnancy is dated back to the first day of your last period, a.k.a. LMP (last menstrual period), even though your baby isn’t conceived until about two weeks after your LMP.

To find your due date, the basic formula is LMP + 280 days. Of course, it’s a little more complicated than that. In 2014, the American College of Obstetrics and Gynecologists updated their guidelines to include an early ultrasound measurement too. In other words, the date could change depending on what your healthcare provider sees on the screen.

Get the full story here about your estimated due date here.

Your Life at 5 Weeks Pregnant

Once you learn you’re pregnant, it can be hard to think about anything else. But it’s OK—a little obsessing is totally normal. Here are a few ways to embrace your new reality.

  • Top tip: Besides excitement, wonder and perhaps a hint of panic, what are among the first thoughts when you find out you’re pregnant? Questions, and lots of them. Why am I so tired? Is caffeine OK? Can I still work out? Here are answers to some of your burning pregnancy questions.
  • Good for your bod: Consider kegels. These below-the-belt exercises not only help promote healing after birth, they’ve been linked to easier labor and delivery, improved bladder control and reduced hemorrhoids. Worth a try! To do them, the general recommended practice is to lift your pelvic floor muscles as if you’re trying to stop yourself from peeing. Tighten for 5-10 seconds, then relax. If you think you may not be doing them right, it’s worth talking to a prenatal physical therapist to help get you on the right track.
  • Snack attack: One word: Popcorn. It’s filled with fiber and has nutrients a pregnant body needs, like zinc and folate. Plus, it’s an easy, tasty way to keep nausea at bay. (Some women swear that constant snacking is the only way they can keep morning sickness under control.) Customize your pop with this recipe for stovetop popcorn (it’s easier than you may think, and oddly satisfying to watch all the popping.)
  • Write it down: Pregnancy is a major life event, but it’s not uncommon to forget the details once your baby arrives. If you hope to look back on the experience as you lived it, get a journal to record your feelings, symptoms and big milestones each week. This can also be a helpful reference during a second pregnancy, or a gift to share with your children once they’re grown with little ones of their own on the way.

Village Tip

Remember to rely on your friends and family throughout your pregnancy. Asking for help can be hard for some people, but practicing reaching out when you could use a hand. (Even if it’s just picking up the one thing you want to eat when everything else makes you queasy.)

Your 5 Weeks Pregnant Belly

You don’t look pregnant yet, but your midsection might feel quite different—bloated and maybe a little crampy. “Weight gain or bloating in the first trimester is usually due to water retention and eating more frequent meals,” explains Dr. Langdon. Light cramps are considered normal, either due to implantation or stretching of the uterus. More severe cramps, like you’d get during your period or worse, aren’t, so let your doc know if you’re feeling any abdominal pain. As for the bloating, you may want to wear stretchier or looser pants than usual (might as well get used to this).

Doctors recommend women gain about 1 to 4 pounds during the first trimester, but honestly you might just be focusing on keeping food down at this point. If that’s the case, don’t worry about the scale and focus on nourishing yourself and your baby however you can.

Your Pregnancy, Week by Week

Want to know what’s going on with both your baby and your body every week? Start your Babylist registry today and get friendly tips and expert advice delivered right to your inbox for each week of your pregnancy (and beyond!).

5 Weeks Baby Bumps from Real Moms




Fun Fact

Before pregnancy, your uterus is about the size of an orange. By the end? We’re talking watermelon!

Do you think this content is helpful? Let our editors know!

5 Weeks Pregnant Checklist

  • Start practicing your kegels. These little movements have big benefits as your pregnant body grows.
  • Find out how your health insurance covers pregnancy and birth.
  • Lay low and rewatch your favorite movie. You probably could use some rest right now. And don’t feel guilty about it—your body is hard at work.
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