4 Weeks Pregnant: Symptoms, Baby Development & Belly Size

Did you know, pregnancy is calculated from the 1st day of your last menstrual period. So when you’re 4 weeks pregnant, your baby—called an embryo—is roughly the size of a poppy seed. The tiny embryo now develops a distinct head and trunk, while its limb buds start forming arms and legs. Its brain, nerves, eyes, and ears begin to take shape, and its heart starts beating rhythmically. While many changes are happening in the background, your pregnant belly will not be visible until the 2nd trimester. So be patient and try to enjoy every new experience your body goes through.

4 Weeks Pregnant: How Big Is Your Baby

The embryo at 4 weeks of pregnancy is only about 2mm long. But it has already started undergoing organogenesis (organ formation) and is developing rapidly. By the end of week 8, this embryo will be called a fetus.

By the 4th week of pregnancy, the fetus has already developed a head, brain, heart and trunk. And organs like arms, legs, eyes, ears and lips have started to form. It’s protected inside an amniotic sac which provides cushioning and is connected to the yolk sac for nourishment.

Is There A Heartbeat At 4 Weeks Pregnant?

Your baby’s heart starts to develop in the 3rd week of pregnancy. And by the end of the 4th week, it starts beating.

What Does A Week 4 Ultrasound Show

A gestational sac, which is a fluid-filled protective sac surrounding the embryo, is the first visible structure on an ultrasound. But it’s visible only after a little over 4 weeks of pregnancy. However, most prenatal ultrasounds are performed in weeks 18th - 20th of pregnancy.

Symptoms Of Being 4 Weeks Pregnant

Being 4 weeks pregnant is too early to experience many noticeable symptoms. But as the pregnancy progresses, the HCG levels in your bloodstream start to rise. HCG or Human Chorionic Gonadotrophin is a hormone secreted by the placenta during pregnancy. The rising levels of HCG in your body cause you to experience many early symptoms of pregnancy such as:

1. 1) A missed period (usually the most common early sign of pregnancy): This is usually the earliest sign of pregnancy. When fertilisation happens, ovulation stops and your body receives signals to stop menstruating.
2. 2) Sore breasts: The hormonal surge during pregnancy causes increased blood flow to your breasts and makes them retain fluid, leading to soreness.
3. 3) Nausea or morning sickness: This is another early sign of pregnancy that happens due to an increase in pregnancy hormones.
4. 4) Period pain-like cramps: You may feel slight cramping, similar to period pain, as the embryo implants in your uterus.
5. 5) Tiredness & fatigue: As your body works hard to support early pregnancy, you end up feeling unusually tired.
6. 6) Food cravings and food aversions: You might suddenly crave certain foods or feel repulsed by the ones you once loved.
7. 7) An increased sense of smell: Scents may seem stronger than usual, making some odours more pleasant and others unbearable.
8. 8) Need to pee more frequently: An increased blood flow and hormonal changes may have you visiting the bathroom more often.
9. 9) Increased vaginal discharge: A whitish, milky discharge is common as your body prepares for pregnancy.
10. 10) Light spotting: Some women experience light spotting or implantation bleeding, which happens when the embryo attaches to your uterus.
11. 11) Hyperpigmentation on the face: Patches of hyperpigmentation, also called the “pregnancy mask,” may start appearing mainly due to hormonal changes.
12. 12) Bloating and gas: Hormonal shifts can cause digestive changes, making you feel gassy or bloated.

Your Pregnant Belly At 4 Weeks: What To Expect

As your developing baby is just a couple of millimetres long at 4 weeks, you won’t notice any change in your belly shape and size. So you might have to wait for another few weeks before you start ‘showing’. For most first-time moms, this happens around the 17-week mark. But for those with subsequent pregnancies, your belly might start showing a bit earlier.

4 Weeks Pregnant? Here Are Some Tips For A Healthy Start

Have you just found out that you’re pregnant? Then here are a few tips you can follow to make sure you have a healthy pregnancy:

1. 1. Schedule Your First Prenatal Visit: It’s best to fix an appointment with your doctor as soon as you discover you’re pregnant. Your doctor will most likely perform blood tests, pelvic exams and other diagnostic tests to look for STDs. They might as well ask several questions to assess any potential risk to the baby (such as a genetic disease that runs in the family) and guide you on the necessary diet and lifestyle changes for a healthy pregnancy.
2. 2. Start With Your Pregnancy Diet & Prenatal Vitamins: What you eat determines your health and that of your baby. So start eating a nutritious diet rich in fruits and vegetables & whole grains. Cut down on unhealthy fat & sugar. And consult your doctor to get started with prenatal vitamins and other necessary supplements.
3. 3. Stay As Active As You Can: Staying physically active is important for maintaining good physical and mental health throughout the pregnancy. So, discuss with your doctor what type of exercise you can safely do during this period. Also, remember to listen to your body and not push limits if you feel breathless or uncomfortable while working out.
4. 4. Get Rid Of Unhealthy Habits: If you drink, smoke or do drugs, now is more important than ever to quit. These habits are known to cause several pregnancy-related complications, birth defects and health problems in the baby. Drinking too much alcohol can even lead to miscarriages.