5 weeks pregnant: Your guide to this week of your first trimester

    Updated 05 July 2023 |
    Published 24 February 2019
    Fact Checked
    Reviewed by Dr. Nazaneen Homaifar, Obstetrician and gynecologist, Inova Health System, Washington, DC, US
    Written by Ella Braidwood
    Edited by Alice Broster
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    From that metallic taste in your mouth to cutting out wine and soft cheese, here’s the lowdown on being 5 weeks pregnant.

    Being 5 weeks pregnant can be a pretty eventful time. After missing your period, you might have taken a pregnancy test and realized that you’re expecting. This can be both exciting and scary at the same time. It’s a monumental change, and it’s very normal to have questions. 

    While you might have only had a few days to process the idea of being pregnant, you’re actually in your second month of pregnancy. This is because your gestational age is calculated from the first day of your last period (the fetal age is calculated from fertilization).  

    Your baby may be too small to see or feel, but you might already be experiencing the emotional and physical changes of pregnancy. It can be comforting to understand what’s happening with your body and your baby at this time. So, keep reading to learn about early pregnancy symptoms and what else you can expect at 5 weeks pregnant.  

    Your baby at 5 weeks pregnant 

    Developing a neural tube

    Your baby is tiny at 5 weeks pregnant — the size of a sesame seed, in fact. However, even at this very early stage of pregnancy, your baby’s nervous system is starting to develop. When you’re around 5 weeks pregnant, your baby will develop a flat, ribbon-like tube called the neural tube, which will eventually become their brain and spinal cord.

    As their neural tube starts to develop, their heart is also starting to form. By 5 weeks of your pregnancy, the foundations for your baby’s organs are also in place. They’ll even have some tiny blood vessels so that blood can begin to circulate.

    Developing eyes 

    When you’re around five and six weeks pregnant, your baby’s eyes will have developed. Two tiny growths will stem from the neural tube and develop into cup-like structures that connect your baby’s optic nerve to their brain. However, they won’t look like eyes as we know them for many months to come. In fact, your baby won’t open their eyes in the uterus for the first time until around 28 weeks

    How big is a baby at 5 weeks? 

    Length (crown to rump): Around 0.08 in. (2 mm)

    Weight: Too small to calculate accurately 

    Size: Equivalent to a sesame seed

    All measurements are approximate and vary within the normal range.

    Your body at 5 weeks pregnant 

    You’re in the very early stages of pregnancy, but you might already be noticing a few changes in your body. It may be these symptoms or a missed period that triggered you to take a pregnancy test

    It’s recommended that you wait until the first day of a missed period before you take a test in order to get the most accurate result. Waiting to take a test might feel tough (living in uncertainty isn’t fun for anyone), but it’s important to leave enough time for your human chorionic gonadotropin levels (the pregnancy hormone that is detected on a test) to be high enough to get an accurate result. And don’t forget that you can use an app like Flo to better understand your cycle and when your period might be considered late. 

    Fatigue

    One of the key changes you might notice at 5 weeks pregnant is feeling more tired than usual. If you find yourself reaching for a blanket by three o’clock., then don’t worry — this is totally normal and easily explained. One of the main reasons you might feel more fatigued than usual is your rising hormone levels. Your progesterone levels rise during pregnancy to support your baby as they develop. This can leave you feeling sleepy. 

    Additionally, during the first few weeks of pregnancy, your placenta will start to develop. To support this, your blood volume increases, and your heart pumps faster and stronger, which can leave you feeling fatigued. 

    Heightened sensitivity to smells and a metallic taste in the mouth

    Fluctuating hormones are also responsible for a heightened sensitivity to smells and a metallic taste in your mouth. If your favorite food is making you feel nauseous, then it could be related to the fact that your hormone levels are fluctuating at this time. 

    Dr. Allison K. Rodgers, reproductive endocrinologist, obstetrician, and gynecologist, Fertility Centers of Illinois, US, explains that your body is starting to adapt to being pregnant during these early weeks. “Your blood pressure starts to drop a bit as your body gets ready to supply the placenta and pregnant uterus with blood,” she says. “Your breast tissue starts developing to support milk production, and your joints will start getting relaxed, which can cause them to be painful.” 

    If you’re starting to experience symptoms, then listen to your body and keep an eye on how you feel. If you are feeling fatigued, then resting can be helpful. It’s also important to note that many people don’t report feeling first-trimester symptoms until six weeks, so don’t be alarmed if you haven’t started experiencing early pregnancy symptoms

    Want to know more?

    Download the Flo app for tailored insights throughout your pregnancy

    Your questions answered  

    Can you feel a baby bump at 5 weeks? 

    You might be really curious to know what your bump will look like, but you won’t have one just yet. Some parents start to see a pregnant belly from around 12 weeks

    Should you rest at 5 weeks pregnant? 

    If you feel tired at 5 weeks pregnant, then listen to your body. You’re currently going through some pretty major hormonal fluctuations, and while having less energy can be frustrating, it’s crucial to rest up. You’re creating a brand-new person from scratch, after all!

    Can you test positive at 5 weeks pregnant?

    The short answer is yes. If you have a 28-day menstrual cycle (this is the average, but anything between 21 and 35 days is considered regular), then you’ll have missed your period at this point. As Dr. Rodgers says, “Most people can have their first positive pregnancy test around 3.5 weeks pregnant or 10 days after ovulation. You should definitely get a positive urine pregnancy test by 5 weeks.”

    Your 5 weeks pregnant checklist

    With so many changes going on, you might be curious as to how you can feel like your best self at 5 weeks pregnant. Luckily, there are a couple of things you can do to take care of yourself and your baby. 

    Make the most of prenatal vitamins

    If you were trying to conceive, then you might already be taking folic acid. However, if you haven’t started yet, then don’t worry. Just start taking it as soon as you discover you’re pregnant. It’s recommended that you take at least 400 mcg of folic acid every day during your first trimester to prevent defects in the neural tube as it grows. Pretty amazing that a vitamin can have such a big impact, right? Just remember that it’s important to speak to your doctor before you start taking any new vitamins or supplements. 

    Leafy greens are your best friend 

    You’ll likely already know the health benefits of eating leafy greens like kale and spinach or other vegetables like asparagus, but at 5 weeks pregnant, these foods might just become your best friends. They are packed with lots of great vitamins and minerals, including calcium, iron, fiber, and folate. “Focus on eating healthy whole foods and limiting processed foods or chemicals,” advises Dr. Rodgers.

    It’s time to cut the wine and soft cheese

    Dr. Rodgers also suggests that once you know you’re pregnant, you may want to consider making a few lifestyle changes. These include not consuming alcohol, nicotine, or recreational drugs and limiting your caffeine intake to 200 mg a day, which is equivalent to a 12-oz. cup of coffee. 

    It can also be really helpful to know which foods to avoid during pregnancy. Unpasteurized dairy, undercooked meat and eggs, and raw sprouts can all be bad for both you and your baby. Fish that’s either uncooked or high in mercury can also be damaging. Sadly, you’ll have to wave goodbye to sushi and charcuterie for now. 

    Exercise to ease early pregnancy symptoms

    Alongside eating healthy whole foods, exercising may help you keep your energy levels up. However, “take care to avoid activities in which you can fall, like sledding, skiing, horseback riding, bike riding, or rollerblading,” advises Dr. Rodgers. This is the time to listen to your body and get as much rest as you need. It’s great to eat healthily and get as much exercise as you can, but it’s also OK to indulge in cravings and take some time to rest when you need it. We are all human, and it’s good to have a balance. 

    When to consult a doctor at 5 weeks pregnant 

    As soon as you’ve got a positive pregnancy test, you can make your first prenatal appointment with your doctor. This is a milestone moment! It’s normal to feel nervous or unprepared, but try not to worry. To put your mind at ease, here are some things to consider at your first prenatal appointment

    • You might be wondering how long your first prenatal appointment will last and how many you’re likely to have. During your first trimester, you’ll get well acquainted with your doctor’s office. You’ll have an appointment roughly every four weeks, and your doctor will do everything from taking your medical history to running frequent blood tests (to check what blood type you are and whether you’re anemic). They will also give you lifestyle tips for a healthy pregnancy, including keeping up a healthy diet, exercising safely, and avoiding substances like alcohol or nicotine that could harm your baby. 
    • If you have had a miscarriage or ectopic pregnancy (when a fertilized egg implants outside of the uterus, usually in the uterine tubes) in the past, then your doctor may want to monitor you a little more closely. Both miscarriage and ectopic pregnancy can be heartbreaking, and if you have any worries or concerns during this new pregnancy, then don’t be afraid to lean on your doctor for support. They should be able to answer all of your questions and concerns, and it’s so important to remember that many people who have had an ectopic pregnancy or miscarriage go on to have healthy pregnancies in the future

    You don’t need to wait until your appointment if you have any concerns or questions about your pregnancy. However, at 5 weeks pregnant, you should contact your doctor immediately if you experience: 

    This isn’t an exhaustive list and just an example of some of the changes you should look out for. Some of these can be a sign of miscarriage or other health complications, so it’s essential that you speak to your doctor about the best next step for you. And if you’re ever worried about any other symptoms you experience during pregnancy, then don’t hesitate to reach out to your health care provider. 

    5 weeks pregnant: The takeaway

    5 weeks pregnant can be a major time for many people, as it often marks the moment they find out they’re expecting. You might start to notice some of the weird and wonderful symptoms of pregnancy, but if you haven’t just yet, then rest assured that it’s perfectly normal at this point. What’s important is to listen to your body and give yourself the space to process the fact that you’re going to be a parent.

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    History of updates

    Current version (05 July 2023)

    Reviewed by Dr. Nazaneen Homaifar, Obstetrician and gynecologist, Inova Health System, Washington, DC, US
    Written by Ella Braidwood
    Edited by Alice Broster

    Published (24 February 2019)

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