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4 Weeks Pregnant: Baby Update

Yes, your baby is tiny—but you might not be feeling so small. One early sign of pregnancy is bloat. This belly blow-up comes courtesy of progesterone, which is currently flooding your body. This hormone helps get blood flowing to the uterus to help it adapt and accommodate your baby’s stay for the next 36 weeks. (By the end of your pregnancy, your progesterone levels could be 100 times what they were pre-pregnancy!) 

Your speck of a baby is burrowing into your uterus, which can cause light spotting. The beginnings of their spinal cord and brain are forming, and they are growing little arm and leg buds…plus a tiny tail! 

How Many Months is 4 Weeks Pregnant?

4 weeks pregnant is just shy of 1 month pregnant.

Baby’s Size at 4 Weeks Pregnant

At 4 weeks, your baby is the size of a grain of sand.

4 Weeks Pregnant: What to Expect

Exciting, exhausting, strange, emotional: The 1st trimester is a rollercoaster. You may be thrilled about your pregnancy, but nervous about telling people too soon. You may be in total shock…or even worried about miscarriage. Rest assured, this major feelings mash-up is completely normal. There’s a lot to wrap your head around! 

And…your body is undergoing massive changes. If this is your first pregnancy, you may not show for months, but you’ll see other developments quickly. Besides bloat, you may be experiencing the following changes. 

4 Weeks Pregnant Symptoms

If you feel tapped of all your energy, remember that deep inside, a teensy, C-shaped embryo is hard at work. 

4 Weeks Pregnant: To-Do List

  • Confirm the pregnancy: This early, an over-the-counter test might miss your pregnancy. These tests are most effective about a week after your skipped period. Do the test in the morning, when your urine is most concentrated. If you get a negative result, try retesting in a week’s time. A doctor can give you a blood test, which is more definitive, but you’ll have to wait a few days for the results.

  • Figure out your due date: If you’ve already been tracking your periods, hurray! This should be easy for you. All you need is the first day of your last menstrual period (LMP). Bring this info with you to your first prenatal visit (though typically these don’t occur until week 8). At that time, some providers will offer a transvaginal sonogram to confirm and date your pregnancy.

  • Drink lots of water. Make sure you’re slurping six to eight glasses of water a day. Staying well-hydrated during pregnancy is incredibly important. Water helps develop the placenta, which delivers nutrients to your baby, and later on, it’ll help form the amniotic sac. It’s also one way to alleviate constipation (progesterone may cause an abrupt digestive slow-down). 

  • Stop smoking and drinking: The American College of Obstetricians and Gynecologists has long advised against drinking and smoking during pregnancy. This is a delicate time for your baby’s development, so if you haven’t stopped yet, it won’t help to beat yourself up, but it will help to quit right away. The sooner you stop the less risk you’ll take on for you and your baby. If you need help, contact the national "quit line" for smoking, 1-800-Quit-Now or Alcoholics Anonymous.

Pregnancy Fun Fact: Interpreting Your Due Date

Most folks give birth between 37 weeks and 42 weeks, and only about 5% of babies are actually born on their due dates. Instead of a due date, think of it as a due month.

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Disclaimer: The information on our site is NOT medical advice for any specific person or condition. It is only meant as general information. If you have any medical questions and concerns about your child or yourself, please contact your health provider.