1, 2 and 3 Weeks Pregnant: Early Signs, Symptoms, and What to Expect

Pregnancy is an exciting journey, and you might find yourself eagerly looking out for very early signs of pregnancy during weeks 1, 2 or 3. However, it may surprise you to learn that you’re not actually pregnant during the first couple of weeks! Don’t worry – it’s a bit of a quirk in how pregnancies are calculated. Keep reading to understand what’s happening inside your body during the first three weeks and what you might expect in these early stages.

Highlights at 1, 2 and 3 Weeks Pregnant

Here are some key highlights of what’s happening during 1st , 2nd and 3rd weeks of pregnancy:

• Watching for Pregnancy Symptoms in Weeks 1, 2 and 3: Are you curious about whether you might notice early signs of pregnancy at 1, 2 or 3 weeks? By week 3, the fertilised egg implants into your uterus, which could cause symptoms like light bleeding or spotting, mild cramps, bloating, or changes in your mood. While these are common signs, not everyone will experience them, so don’t worry if you don’t notice anything yet.

• Calculating Your Due Date: Most GPs track pregnancy along 40 weeks, starting from the first day of your last menstrual period (LMP). This means you aren’t technically pregnant until fertilisation occurs, typically between weeks 2 and 3.

Your First Three Weeks of Pregnancy

Here’s an interesting fact–because pregnancy is measured from the first day of your last menstrual period (LMP), you’re technically not pregnant during the first two weeks. The average pregnancy length is 40 weeks (280 days), even though conception happens later. Let’s break it down:

• 1 week pregnant. You’re having your period.

• 2 weeks pregnant. Ovulation is likely occurring. If you have a 28-day cycle, ovulation happens around 14 days after your period begins, paving the way for fertilisation and conception.

• 3 weeks pregnant. Fertilisation and implantation may occur, marking the earliest point at which you’re truly pregnant.

While you may not notice any 1-week pregnancy symptoms or 2-3 weeks pregnant symptoms, your body is already hard at work preparing for this incredible journey.

How to Determine Your Due Date?

Wondering when your baby might arrive? It’s natural to start thinking about your due date as soon as you find out you’re pregnant – it’s such an exciting time!

Try our Due Date Calculator to get an estimate. Simply enter the first day of your last menstrual period (LMP) or, if you know it, the date of conception.

Most GPs calculate your due date using the LMP method. Once you start noticing pregnancy symptoms after week 1 or feel you might be pregnant, take a home pregnancy test and follow up with your GP to confirm your pregnancy. They may also help you calculate your due date, giving you a clearer idea of when to expect your little one!

How Many Months Is 1 to 3 Weeks Pregnant?

Your GP will predominantly refer to your pregnancy in weeks, but you might also hear months being mentioned. The nine months of pregnancy don’t divide evenly into weeks, so there are different ways to calculate how weeks correspond to months. Typically, the first month of pregnancy includes the first four weeks. This means that at 2-3 weeks pregnant, you’re still in your first month, even if you haven’t noticed a belly bump or many symptoms just yet!

Your Symptoms at 1, 2 and 3 Weeks Pregnant

Your pregnancy journey is underway, but as mentioned above, you’re not actually pregnant yet. This may seem mind-boggling, and it’s common to wonder if there are any symptoms during the first 72 hours of pregnancy or in the first couple of weeks. Again, because of the way pregnancy is calculated, many people don’t notice any symptoms during these early days. However, after about 2 weeks pregnant, significant changes start to happen in your body:

• Egg Release:  Ovulation, the release of an egg from your ovary, usually occurs 10 to 16 days before your next period. In women with a regular 28-day cycle, ovulation typically happens around day 14, though this may vary for shorter or longer cycles.

• Fertilisation:  If sperm meets the egg during its journey down the fallopian tube, fertilisation occurs. The fertilised egg will carry the genetic building blocks that determine many characteristics of your future baby. This fascinating process also determines your baby’s sex.

• First DNA:  At this stage, the fertilised egg is now called an embryo. It combines chromosomes from the egg and sperm, laying the groundwork for your little one’s unique genetic makeup.

• Development: This is the stage when the embryo travels from the fallopian tube to the uterus, where it attaches to the uterine lining in a process called implantation. This important step triggers the release of pregnancy hormones, which prevent the uterus lining from shedding. This is why you’ll typically miss your period when you’re pregnant.

What this all means is that you’re unlikely to feel any very early signs of pregnancy during weeks 1, 2 or even 3. If conception hasn’t occurred yet, it’s completely normal not to notice anything. This means that things like morning sickness won’t start at 1 week pregnant, and symptoms such as pregnancy-related belly pain or discharge are unlikely at 1 or 2 weeks pregnant either.

Typical Early Signs of Pregnancy

As mentioned, during weeks 1, 2 or 3, you may not even realise you’re pregnant, and it’s likely you won’t have experienced any pregnancy symptoms. After all, it’s still very early, and you might not have even conceived until you’re 3 weeks pregnant. However, in the weeks that follow, there are several signs of pregnancy you could experience:

• A Missed Period A missed period is often the first clue of pregnancy, but it won’t happen until you’re 4 weeks pregnant – not before. Around the time you miss a period, you may start noticing more early pregnancy symptoms.

• Implantation Bleeding  Implantation bleeding is another potential early sign of pregnancy. It occurs when the fertilised egg, now a tiny ball of cells, attaches to the lining of your uterus. Not everyone experiences it, but if you do, this light spotting is perfectly normal and is sometimes mistaken for a period. Spotting, mild cramps, or light bleeding usually happens 10 to 14 days after conception, which is around 3 to 4 weeks pregnant.

• Morning Sickness  Morning sickness is one of the more well-known symptoms of early pregnancy. Despite its name, it may occur at any time of the day. Nausea or vomiting typically begins between weeks 4 and 9 of pregnancy.

• Other Symptoms  Other early pregnancy symptoms may include gas, fatigue, tender breasts, mood swings and frequent urination. These may appear in the early weeks and vary greatly from person to person.

What Size Is a Pregnant Belly at 1, 2 and 3 Weeks?

Every pregnancy is unique, so it’s possible to notice that bump earlier or later than other pregnant women. At 1-3 weeks pregnant, it’s unusual to have any increase in the size of your belly. Remember that you’re not actually pregnant during those first two weeks and it’s still early during the third week.

What Size is Your Baby at 3 Weeks?

Although your bump won’t be noticeable at 3 weeks pregnant, your baby's development is underway inside your belly, with cells dividing and multiplying. By around 3 weeks into your pregnancy, your little one is just a tiny collection of over 100 cells, known as an embryo – too small for a bump to appear just yet.

How Early Can You Tell If You’re Pregnant?

You might be wondering if you can confirm your pregnancy at 1, 2 or 3 weeks pregnant. While it’s possible to get a positive result on a pregnancy test at 3 weeks, it’s generally best to wait until after you’ve missed your period for more accurate results. That’s because a home pregnancy test works by detecting the hormone human chorionic gonadotropin (hCG) in your urine. This hormone starts to increase shortly after conception. Although your hCG levels might be high enough in week 3 to show a positive result, it’s always a good idea to confirm your pregnancy with your GP.

How Far Along Are You?

Understanding how far along you are in pregnancy might help your GP monitor your baby’s growth and development, keep track of your health, and schedule important tests and check-ups.

Pregnancy is divided into three trimesters:

• First trimester: Covers weeks 1 to 13 (roughly months one to three).

• Second trimester: Covers weeks 14 to 27 (months four to seven).

• Third trimester: Covers weeks 28 to 40-42 (months seven to nine). 40 weeks is considered full-term, but some pregnancies may extend to 42 weeks 

Check out the illustration below to help you work out how far along you are in your pregnancy:

What Precautions Should You Take During Early Pregnancy?

Even if you haven’t noticed any very early signs of pregnancy during weeks 1, 2 or 3, it’s important to take steps to stay healthy and safe. It’s a good idea to start taking precautions as soon as you’re trying to conceive or find out you’re pregnant.

Lifestyle Adjustments

Simple lifestyle changes may go a long way in supporting you during the early stages of pregnancy. While you should always consult your GP or midwife for tailored advice, some helpful adjustments include:

• Eating a healthy, balanced diet

• Staying hydrated

• Reducing stress

• Getting regular, moderate exercise.

Folic Acid

As soon as you start trying for a baby or find out you’re pregnant, taking folic acid is crucial. This B vitamin helps reduce the risk of neural tube defects, which affect the development of your baby’s brain and spine. It’s recommended that you take a supplement containing at least 400 micrograms of folic acid daily. Your GP or midwife may help you choose the right prenatal vitamin.

Eliminating Bad Habits

Pre-pregnancy is the ideal time to eliminate less healthy habits, including:

• Smoking

• Exposure to secondhand smoke

• Drinking alcohol.

Your GP or midwife may also recommend limiting your daily caffeine intake. Speak with them to find out the best ways to stay healthy and safe as you prepare for pregnancy and the months ahead.

For more general advice, download our pregnancy guide!

1 to 3 Weeks Pregnant: Your Checklist

This exciting time brings many responsibilities and things to consider. For a little help on your journey, here’s a simple checklist:

□ If you’ve already taken a pregnancy test before missing your period, consider taking another one after your missed period for the most accurate results.

□ Schedule an appointment with your GP to confirm your pregnancy with a blood test.

□ Explore our pregnancy calendar to discover what to expect throughout your pregnancy journey.

□ It’s still much too early to find out your baby’s gender, but you can still have some (completely unscientific) fun with our Chinese Gender Predictor!

Bottom Line

Pregnancy is an exciting journey filled with unique milestones and experiences. As you navigate these early weeks, remember to consult your GP for personalised advice and support. For extra help along the way, download the Pampers Club app. The app offers rewards for all those nappy and wipes purchases you will be making, helping support you during this new parenting adventure.

_{How We Wrote This Article The information in this article is based on the expert advice found in trusted medical and government sources, such as the National Health Service (NHS). You can find a full list of sources used for this article below. The content on this page should not replace professional medical advice. Always consult medical professionals for full diagnosis and treatment.}