5 Weeks Pregnant: Baby, Body and What to Expect

Week 5 at a glance

At week 5, your baby is about the size of a sesame seed. The main development this week is the neural tube, which becomes the brain and spinal cord.

5 weeks pregnant is about 1 months. You are in month 2 of pregnancy and the first trimester.

Your baby at 5 weeks

Your Baby Is the Size of a Sesame Seed

Baby's development this week

At this stage, the embryo is about 2 mm (0.08 in) long. The heart is starting to form and may begin beating soon, around this week or the next.

The neural tube is forming and will become the brain and spinal cord
The blood vessels and circulatory system begin to develop
Early forms of major organs begin to appear

Many providers recommend taking 400 micrograms (mcg) of folic acid every day before and during early pregnancy. Folic acid helps lower the risk of neural tube defects. Ask your doctor or midwife what dose is right for you.

Many home pregnancy tests can detect the hormone hCG by about this time. Test results depend on the test you use and when you ovulated, so a negative test early on does not always rule out pregnancy. Pregnancy is counted from the first day of your last menstrual period, so week 5 is about 3 weeks after conception.

Call your doctor or midwife right away if you have heavy bleeding, severe belly pain, or pain on one side of your belly with dizziness or shoulder pain. These can be signs of a problem such as an ectopic pregnancy or miscarriage.

See week 5 in 3DNova shows how your baby grows each week and keeps a symptom log for your doctor. Try Nova

Your body at 5 weeks

Changes in Smell and Taste

Why Do Smells Seem Stronger?

Many pregnant people notice that familiar smells, such as morning coffee, perfume, or cooking food, suddenly feel overpowering. Researchers think this may be related to hormone changes early in pregnancy.

Rising levels of estrogen and hCG (human chorionic gonadotropin, often called the pregnancy hormone) may make the sense of smell more sensitive. Some researchers believe this heightened sensitivity may help people avoid foods that could be unsafe, but this is not yet proven.

Taste Changes: Is This Normal?

Taste can change too. Many people notice a metallic taste in their mouth or suddenly dislike foods they used to enjoy. These changes are common in early pregnancy and are usually temporary.

A metallic taste (dysgeusia) is a common, usually temporary change during early pregnancy.
Shifting food preferences, such as sudden cravings or dislike of favorite foods.
Stronger reactions to cleaning products, perfume, and smoke.

How to Cope

These reactions can be hard to avoid completely. Many providers suggest you ask your doctor or midwife for food and nutrition ideas that may help with discomfort.

Try cold or room-temperature foods, which often have milder smells.
Open windows and run a fan to keep strong odors from building up.
Try lemon, mint, or ginger to help with unpleasant tastes.

Contact your provider right away if smell or taste changes come with trouble keeping down fluids or food, vomiting that won't stop, dizziness, very dark urine, or peeing much less than usual. These can be signs of dehydration, and you may need medical care.

Common symptoms at 5 weeks

Smell sensitivity

Smells you used to ignore, like coffee, cooking food, or cleaning products, may suddenly feel strong or unpleasant. Keeping windows open, choosing unscented products, and asking someone else to handle strong odors can help.

Nausea

Some people feel queasy at any time of day, often triggered by smells or an empty stomach. Eating small, frequent snacks and keeping crackers by the bed may ease it.

Tiredness

Feeling worn out, even after a full night's sleep, is very common early in pregnancy. Short rests, an earlier bedtime, and lighter plans for the day can make a difference.

Breast tenderness

Breasts may feel sore, swollen, or sensitive to touch. A supportive bra, especially one worn at night, may feel more comfortable.

Frequent urination

You may need to pee more often as your body makes more blood and hormones. Drinking water steadily through the day, and cutting back on caffeine late in the day, may help with nighttime trips.

Changes in taste

Foods may taste metallic, bland, or different than usual, and some favorite foods may suddenly seem unappealing. Trying cold or room-temperature foods, or adding a squeeze of lemon, may make eating easier.

Your week 5 checklist

Start or keep taking a prenatal vitamin with folic acid, as your care team advises. Keep a few easy snacks, like crackers, fruit, or yogurt, within reach. Drink water through the day and keep a bottle nearby. Write down your questions for your first prenatal visit. Rest when you can and ask for help with heavy chores. Choose a prenatal care provider if you have not already.

For your partner: Your partner can help by taking over strong-smelling chores, like cooking or cleaning, and by keeping the house well ventilated. Offering quiet support, practical help with meals, and patience with mood or fatigue can make this stage feel easier.

Questions about week 5

How many months is 5 weeks pregnant?

5 weeks pregnant is about 1 months. You are in month 2 of pregnancy and the first trimester.

What trimester is 5 weeks?

Week 5 is in the first trimester. The first trimester runs through week 13, the second from week 14 to 27 and the third from week 28 until birth.

What is happening with the baby at 5 weeks?

At week 5, your baby is about the size of a sesame seed. The main development this week is the neural tube, which becomes the brain and spinal cord.

Why do smells bother me so much at week 5?

Rising hormones, including hCG and estrogen, are thought to make your sense of smell more sensitive. This is common and often eases as pregnancy goes on. Avoiding strong triggers and getting fresh air can help in the meantime.

Is it normal to feel tired this early?

Yes, fatigue is one of the most common early pregnancy feelings. Your body is working hard to support early growth. Rest when you can, and talk with your care team if tiredness feels severe or you feel unwell.

Can I still eat foods I dislike or find hard to taste?

Many people find their taste changes shift week to week. Choose foods that feel comfortable, eat small amounts often, and include nutritious options when you can. Ask your care provider if you have concerns about eating enough.