Week 5 of Your Pregnancy

Verywell / Bailey Mariner

You’re officially pregnant! You may have noticed something missing this week—your period. A missed period is what typically leads most people to take a pregnancy test. That positive result can bring a flood of reactions from excitement to fear. And, while your baby might be too small to see, at 5 weeks pregnant, you may already be feeling its presence both physically and emotionally.

5 Weeks Pregnant Is How Many Months? 1 month and 1 week

Which Trimester? First trimester

How Many Weeks to Go? 35 weeks

Your Baby's Development at 5 Weeks

At 5 weeks, a baby measures approximately 1/17th of an inch or 1.5 mm. That's about the size of a strawberry seed. The baby is growing rapidly, and the major organ systems of their body are beginning are to form, specifically the brain and the heart.

At 5 weeks pregnant, your baby is about the size of a bristle on a hair brush
Verywell / Bailey Mariner 

Layers of Development

At this time, your little embryo begins to lengthen and take on the appearance of a tadpole thanks, in part, to the development of the all-important neural tube that runs from the top to the bottom of the embryo. (This tube will grow to become the spinal cord and brain.) There’s even a tiny blip at the center of the embryo that will soon develop into baby’s heart.

Inside of your embryo, the cells are separating into three layers to form different body systems:

  • The ectoderm or outer layer is beginning to form the nervous system, including your baby's brain and spinal cord. It will also create your baby's skin, hair, and nails.
  • The mesoderm or middle layer is becoming your baby's circulatory system with the development of your baby's heart and blood. It will also develop into the bones, muscles, and kidneys.
  • The endoderm or inner layer will eventually become your baby's lungs, intestines, and liver.

Gestational Sac

The gestational sac is a ball of fluid that forms around your developing baby. At 5 weeks, your embryo is too small to see yet, but the gestational sac may be visible on an ultrasound. 

Explore a few of your baby’s week 5 milestones in this interactive experience.

Stay Calm Mom: Episode 2

Watch all episodes of our Stay Calm Mom video series and follow along as our host Tiffany Small talks to a diverse group of women and top doctors to get real answers to the biggest pregnancy questions.


A Positive Pregnancy Test: Now What?

Your Common Symptoms This Week 

The level of the pregnancy hormone hCG in your body is on the rise, which brings not only a positive pregnancy test but also early pregnancy symptoms. It's important to know, however, that some people don’t experience any symptoms and the lack of symptoms in no way reflects the health and well-being of their growing babies. Even having experienced symptoms in a prior pregnancy can’t predict how you will feel this go-round.

Missed Period 

The absence of menstruation is often one of the first signs of pregnancy that alert a person to take a pregnancy test. The increased production of progesterone during pregnancy prevents your uterine lining from shedding and helps maintain your pregnancy.

Breast Changes

Your breasts may feel tender, tingly, or larger. You are more likely to experience early breast changes if you tend to notice them before your period.


Your body is working hard, and you are going through many physical and emotional changes. It’s perfectly normal to feel tired and in need of a nap. Fatigue is considered a universal symptom this early in pregnancy.

Morning Sickness

Nausea, with or without vomiting, is one of the most common discomforts of pregnancy. The exact cause isn’t known, but experts believe the quick rise of pregnancy hormones may be the culprit. It is typical during the first three months, although it can last longer. And, despite being called morning sickness, the queasiness can come on at any time during the day.

Extra Bathroom Trips

Frequent urination is a common complaint even this early in pregnancy. Those pregnancy hormones cause an increase in blood flow and fluid in your body. So, your kidneys are working overtime to get rid of the waste. 

 A Range of Emotions

There is no one universal emotion or feeling that every person who is pregnant experiences and your feelings about your pregnancy may change from week to week or even hour to hour. Whether you’re excited to learn you’re pregnant or not, it’s important to know that pregnancy can be emotionally complicated. Just remember that your reaction—whether positive, negative, or ambivalent—is normal.

What Experts Say

“You may even surprise yourself by your reaction. The most important thing is that you don’t feel guilty about how you feel.” 

Shara Marrero Brofman, PsyD

Self-Care Tips

Most people find out they're expecting during week 5. Learning that you're pregnant can be overwhelming, but so can thoughts of all you have to do to prepare over the next 35 weeks. Take a deep breath and take it one step at time.

End the Wait

If you haven’t already, it’s time to take the big test. A positive home pregnancy test on the first day of your missed period is up to 99% accurate.

Take Folic Acid

Continue to take a folic acid supplement or prenatal vitamins. As your baby’s nervous system is forming, folate is an essential nutrient that helps prevent neural tube defects. 

Make Safe Food Choices

You don't have to give up all your favorite foods now that you're pregnant. A healthy pregnancy diet is balanced, and you can still enjoy some less nutritious treats now and then. But, some foods can increase your risk of illness and infection, which can be dangerous to your developing baby. You will want to stay away from:

  • Unpasteurized cheeses, such as brie and feta
  • Raw or unpasteurized milk or juice
  • Uncooked or undercooked meats, poultry, seafood, and eggs
  • Uncooked smoked seafood such as lox or seafood jerky
  • Fish containing high levels of mercury like swordfish, tilefish, shark, mackerel, and bigeye tuna
  • Raw dough including cookie dough and cake batter

Learn About Pets and Pregnancy

It is typically not dangerous to have pets such as a cat or dog during pregnancy. But, all animals have the potential to cause harm or pass diseases to their humans. You can keep yourself, your unborn baby, and your pet healthy and safe by talking to your doctor and the vet about the best way to care for your pet while you’re expecting and after you bring your new baby home.

Visit the Dentist

While you’re likely hyper-focused on scheduling—and going to—your first prenatal appointment, you should also consider making an appointment to see a dentist. In fact, the American Dental Association, the American Congress of Obstetricians and Gynecologists (ACOG), and the American Academy of Pediatrics (AAP) all encourage people to see the dentist while they are pregnant.

The same hormonal changes that bring about nausea and breast tenderness can cause gum inflammation (pregnancy gingivitis). If ignored, pregnancy gingivitis may lead to a more serious gum infection called periodontitis, which increases the chance of preterm birth.

Avoid Pregnancy Dangers

Staying away from toxic substances during your entire pregnancy is wise. However, the first trimester is particularly crucial. During the embryo stage, your baby's organs and tissues are developing. It's a sensitive time when outside influences can affect your baby's body parts as they form.

Talk to your doctor about any prescriptions, over-the-counter medicine, or herbal supplements you're taking. You should also avoid harmful substances such as alcohol, smoking (including second-hand smoke), and recreational drugs as well as potentially hazardous activities such as sitting in a hot tub, going on a roller coaster, or getting a tattoo.

Your Week 5 Checklist

Advice for Partners

Learning that you and your partner are soon-to-be parents is heavy for both of you, whether your pregnancy was planned for or not. While they may be going through the physical symptoms, both of you are going through a natural emotional roller coaster. Compassion and empathy all around is always the way to go.

What Experts Say

“Try your best not to minimize stresses or insecurities. At the same time, both parties should seek out emotional and practical support from books and friends.”

Shara Marrero Brofman, PsyD

At Your Doctor’s Office

Once you learn that you are pregnant, go ahead and call the doctor to schedule your first prenatal appointment. Don’t forget to have the date of your last menstrual period ready to share.

Your doctor may want you to go to the office or to a lab to have your blood drawn before your appointment. Blood tests can confirm a home urine pregnancy test.

If you are high risk or undergoing fertility treatments, you may have blood drawn to check these numbers a few times. You may also have an ultrasound this week to check for a gestational sac. Your embryo is too small to see yet, but the gestational sac may be visible when your hCG level is around 2000 mIU/ml.

Upcoming Doctor's Visits

Your first prenatal appointment is right around the corner. You'll likely see the doctor sometime in week 6, week 7, or week 8.

Special Considerations

Now that you know you're pregnant, you may be wondering about your due date, worried about the health of your pregnancy, or concerned about upcoming travel plans and dangers.

Calculating Your Due Date

Your doctor will calculate your due date at your first prenatal visit, but you can figure it out yourself. Pregnancy lasts 280 days or 40 weeks from the first day of your last period. You can:

  • Look at a calendar, find the day your last period started, and count 280 days or 40 weeks forward.
  • Ignore the year, take the first day of your last period, subtract three months, and add seven days.

Ectopic Pregnancy

An ectopic pregnancy is a pregnancy outside of the uterus, usually in the fallopian tube. It occurs in approximately 1% to 2% of pregnancies. An ectopic pregnancy is dangerous, so symptoms such as vaginal bleeding, pain, and dizziness should be reported to your doctor right away. If you are at risk for an ectopic pregnancy, or there is any concern about your pregnancy, your doctor will order blood work and an ultrasound.

The Zika Virus

Pregnant individuals should avoid traveling to areas in the United States and worldwide where there’s a risk of contracting the Zika virus. The virus and resulting fever can lead to several birth disabilities, including microcephaly in which babies develop smaller-than-normal heads and possible brain damage.

Zika is spread by infected mosquitoes and through sexual contact with an infected person. Since there is no vaccine and no cure, it’s essential to check the CDC’s Travel Health Notices to see the most current areas where the Zika virus is spreading.

If you must travel to an area where Zika risk is high, talk to your doctor first. Learn how to properly prevent mosquito bites and protect yourself when engaging in sexual activity.

A Word From Verywell

Week 5 brings big news. It’s amazing how two little lines or a plus sign could be so life-changing. As it begins to sink in, you may be feeling your first pregnancy symptoms. Next week may bring an increase in symptoms, your first prenatal doctor visit, and the possibility of seeing a tiny heartbeat.

18 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Hill, MA. Carnegie stage 8. Embryology.

  2. Kiecker C, Bates T, Bell E. Molecular specification of germ layers in vertebrate embryos. Cell Mol Life Sci. 2016 Mar 1;73(5):923-47. doi:10.1007/s00018-015-2092-y

  3. Connolly A, Ryan DH, Stuebe AM, Wolfe HM. Reevaluation of discriminatory and threshold levels for serum β-hCG in early pregnancy. Obstet Gynecol. 2013;121(1):65-70. doi:10.1097/AOG.0b013e318278f421

  4. Dante G, Vaccaro V, Facchinetti F. Use of progestagens during early pregnancy. Facts Views Vis Obgyn. 2013;5(1):66-71.

  5. Eunice Kennedy Shriver National Institute of Child Health and Human Development. What are some common signs of Pregnancy? U.S. Department of Health and Human Services.

  6. Lee NM, Saha S. Nausea and vomiting of pregnancy. Gastroenterol Clin North Am. 2011;40(2):309-34. doi:10.1016/j.gtc.2011.03.009

  7. Bienstock JL, Fox HE, Wallach EE, Johnson CT, Hallock JL. Johns Hopkins Manual of Gynecology and Obstetrics. Lippincott Williams & Wilkins.

  8. National Health Service. Feelings, Relationships, and Pregnancy.

  9. Office of Women’s Health. Pregnancy Tests. U.S. Department of Health and Human Services.

  10. Ami N, Bernstein M, Boucher F, Rieder M, Parker L. Folate and neural tube defects: The role of supplements and food fortification. Paediatr Child Health. 2016;21(3):145-54. doi:10.1093/pch/21.3.145

  11. Food and Drug Administration. Food Safety for Pregnant Women. U.S. Departments of Agriculture and Health and Human Services. fda.gov.

  12. Stull JW, Brophy J, Weese JS. Reducing the risk of pet-associated zoonotic infectionsCMAJ. 2015;187(10):736-743. doi:10.1503/cmaj.141020

  13. American College of Obstetricians and Gynecologists. Committee Opinion No. 569: oral health care during pregnancy and through the lifespan. Obstet Gynecol. 2013;122(2 Pt 1):417-22.

  14. Alwan S, Chambers CD. Identifying human teratogens: An update. J Pediatr Genet. 2015 Jun;4(2):39-41. doi:10.1055/s-0035-1556745

  15. You're Pregnant: Staying Healthy and Safe. U.S. Department of Health and & Human Services Office on Women's Health.

  16. American College of Obstetricians and Gynecologists. ACOG Committee Opinion No 579: definition of term pregnancy. Obstet Gynecol. 2013 Nov;122(5):1139-40.

  17. Panelli DM, Phillips CH, Brady PC. Incidence, diagnosis and management of tubal and nontubal ectopic pregnancies: A review. Fertil Res Pract. 2015;1:15. doi:10.1186/s40738-015-0008-z

  18. Centers for Disease Control and Prevention. What We Know About Zika and Pregnancy.

Additional Reading
  • Allison Hill, MD. Email communication. October, November 2017.

  • Shara Marrero Brofman, PsyD. Email and Phone Communications. October, December 2017.

By Holly Pevzner
Holly Pevzner is an award-winning writer who specializes in health, nutrition, parenting, and family travel.