Skip to main content
Baby Corner logo
Login | Sign Up

Pregnancy Week 4


Welcome Guest! Update DueDate and Newsletter Subscription

Fetal Development Images - Pregnancy  4
Week 4 fetal development image showing the fetal growth of your baby to date. Medical Illustration Copyright © 2008 Nucleus Medical Art, All rights reserved

View Larger Image

Baby Development

Roughly the size of a poppy seed, your baby is now entering the phase of development known as the embryonic period. The cluster of cells that is becoming baby has traveled down the fallopian tubes and have settled into the uterus, where the next big task is to divide in half. One half of the cells become the placenta while the other half becomes baby. The baby cells divide further, into three groups. The first, the inner layer, is called the endoderm. The endoderm develops into the digestive system, liver, lungs, pancreas and thyroid. The middle layer, or mesoderm, becomes heart, reproductive organs, bones, kidneys and muscles. The outer layer, or ectoderm, becomes brain, spine, nerves, skin, hair, eyes, teeth, sweat and mammary glands. The amniotic sac and yolk sac are forming now as well. The yolk sac eventually will become part of the digestive system.

Pregnancy Symptoms

Sounds a lot like PMS, doesn't it? Early pregnancy symptoms are quite similar to premenstrual syndrome. You might feel more breast tenderness than you usually would with your period however, and your breasts might be enlarged somewhat. You may feel some abdominal pressure and might experience implantation bleeding. This is spotting, and may be light pink, red or brown. It happens when the embryo implants itself into the uterine wall. It's not rare, but certainly not unexpected either. Whether you have spotting or not, you need not worry.

Visit With the Obstetrician

Usually you won't be seeing a physician for your pregnancy until your 8th week or so. However, you will be taking a home pregnancy test at this point most likely. If it is negative, wait a week and retest. Sometimes the pregnancy hormone, hCG, is still too faint at 4 weeks for many tests to pick them up. You can begin looking for a doctor or health care provider, and might interview the most promising prospects to see if you have a good match in expectations.

Preparing for Baby

This is a great time to just start reading up on early pregnancy.

  • What foods are no-no's?
  • Which healthy foods should you be eating?
  • What is recommended for exercise during pregnancy?
  • Is pregnancy going to be an issue with your work?
  • Will you need to make some changes at the work site or to your schedule?
  • What is the maternity leave policy at your job?
  • Thinking ahead, not worrying, is a good way to start preparing mentally for this new pregnancy.

Pregnancy Lifestyle

Check that medicine cabinet. Are there prescriptions drugs you take regularly? If so, read up on them or talk to your pharmacist about the safety of taking them while pregnant. If you find out a drug you take can be dangerous in pregnancy, talk to the prescribing physician immediately. Don't wait until your prenatal visits begin. Also, check on any over the counter medications to see if they are safe to take while pregnant.

Pregnancy Week 4 Comfort Meter

I feel absolutely wonderful!
I feel pretty good!
I could be feeling better
UGG I feel terrible!


Showing 1 - 10 out of 116 Comments
Add Comment or question.

Keagalemang Aug 4, 2018 08:30:29 PM ET

It's normal to have pain when you are pregnant.

Reply | Report

Joyce Jul 11, 2018 09:36:07 AM ET

I saw my period June 2 2018 and I had sex 16 and I haven't seen my period for July. I did the pregnancy test and it was positive ,so how many weeks am I pregnant?

Reply | Report

regs Sep 29, 2016 12:39:03 AM ET

Hello. I am 10 days late now. Supposedly my menstruation should have arrived last Sept 20th, yet it hasn't come. I have taken a pregnancy test last Sept 25th, it says negative. I frequently urinate and my BBT rise higher until now. I just want some advice before going to OB. Hope you'll share some. Thanks.

Reply | Report

jjesslouisee Sep 20, 2016 08:25:00 AM ET

I'm really tired, bloated, and have had headaches for the past 2 weeks. A week ago, I was spotting for 2 days. It was a week before my period was due. My period is now 3 days late and all my tests have been a BFN. Could I still be pregnant?

Reply | Report

anthony Mar 1, 2015 05:05:12 PM ET

Is it safe to have sex with a woman that is 3 weeks pregnant?

Guest Mar 22, 2015 06:52:14 PM ET

It's safe to have sex with a pregnant woman, as long as it's comfortable no matter the week she's at. at 3 weeks, people don't usually know yet, and shouldn't notice any difference.

Heather Jul 5, 2018 09:36:19 PM ET

Just don't have sex at 8 months because it will put you in preterm labor, it happened too me.

Reply | Report

Tender nipples Feb 24, 2015 10:57:17 PM ET

My period was 5 days late, but on Feb 5th, I had somewhat of a period. It was 4 days long and somewhat light. Now, two weeks later, I have had tender nipples for almost a week with lower back pain.

Reply | Report

Guest Feb 14, 2015 12:24:07 AM ET

I had sex (unprotected) in January, and it's now Feb 13. I've noticed my stomach looks a bit bigger. I've been a bit constipated, and have had a few headaches. I'm also a bit emotional. I'm really scared that I might be pregnant, and need some advice! :(

Guest Apr 11, 2015 02:35:36 PM ET

Take a home pregnancy test to see if you're pregnant. be sure to check any medications that maybe dangerous to take. seek an obgyn as soon as you can. most symptoms occur the first 8 weeks. but sometimes you can feel them as early as 5 weeks.

Reply | Report

Jordan Feb 5, 2015 11:24:41 PM ET

I don't remember the last time I had my period, but I know that it was in December. My boyfriend and I are very sexually active, and he doesn't pull out ever. Just a couple days ago, I started getting headaches and period like cramps. I've been getting really moody. I didn't have my period at all last month, and I'm scared that I'm pregnant. So could I be?

Heather Jul 5, 2018 09:33:32 PM ET

Hunny, if you didn't have your period last month you're pregnant. i'm working on trying to have a baby except this will be my third baby. i've had. try keeping a bunch of ovulation test around and take one before you get ready to have sex with your man, so you know to tell him to pull out around that time. signs of pregnancy: late on your monthly, nauseous, sometimes morning sickness, exhausted all the time, restless at night, craving weird foods that's not your usual, constipation, usually you tend to tell people what to do or are bitchy at them , sometimes irritation, clothes getting tighter more and more, want to sleep more and more, your sleep schedules all messed up, tender breast, lower back pain and you feel like you are cramping like your gonna start your period but you miss your period.. now my first baby i had, i was on my period for 5 months until i showed up on the pregnancy test that i was pregnant and i got a obgyn and they said i was 5 months pregnant, thinking i might be a week pregnant. it's to early to tell of the pregnant year test so i've had experience.

Reply | Report

Louise Jan 27, 2015 07:39:04 PM ET

Hey... I had unprotected sex twice 8 or 9 days ago. Since then, I've had cramps in my stomach, and a sore back. I also had cramps in my legs. This morning, I woke up with a creamy discharge there, and there was quite a lot of it!. So, I took a pregnancy test, and it was negative. I'm not due for my period for about a week and a half. Shall I wait until then? If it's late, should I take one again? I also have a doctor's appointment next Wednesday! Even though I have a negative result, is there a chance I could be still pregnant?

Reply | Report

magi Dec 28, 2014 08:34:04 AM ET

Well, I'm 20 days late on my period so here is my story. I was pregnant and lost it at weeks. Then, I got the depo shot after the 3 months were over. I didn't get it because I wanted my period, so I waited and 2 month passed. Then, my period never came and the doctors started me on the pill. Can I still be pregnant even though I'm on the pill? By the way, all tests were negative. I just need advice. I'm scared.

magi Jan 8, 2015 08:44:10 AM ET

Well now i'm 28 days late and still have a negative test. but, today, i had some light pink discharge (sorry tmi) in the morning and evening, and some cramping, but nothing now. can anyone help me out?! i'm going to make an appointment hopefully in 2 weeks just to see what happens.

Reply | Report

1 2 3 4 5 6 7 8 9 10 Next >>

Add Comment

You are commenting as Guest.

Pregnancy Week by Week Personalized For You
See how your baby grows each week throughout your pregnancy with advice and tips for what to expect.

Enter Your Due Date

Pregnancy Week by Week

Not sure of your due date? Find out with our due date calculator.

New Today at Baby Corner

Pregnancy Community