Pregnancy information

You and your pregnancy at 1 to 3 weeks

Your weeks of pregnancy are dated from the first day of your last period.

This means that in the first 2 weeks or so, you are not actually pregnant – your body is preparing for ovulation (releasing an egg from one of your ovaries) as usual.

Your "getting pregnant" timeline is:

  • day 1: the first day of your period
  • day 14 (or slightly before or after, depending how long your menstrual cycle is): you ovulate
  • within 24 hours of ovulation, the egg is fertilised by sperm if you have had sex in the last few days without using contraception
  • about 5 to 6 days after ovulation, the fertilised egg burrows into the lining of the womb – this is called implantation
  • you're now pregnant

You at 1 to 3 weeks

The first thing most women notice is that their period does not arrive.

Find out about the signs and symptoms of pregnancy

The most reliable way of finding out if you're pregnant is to take a pregnancy test.

Once you think you?could be?pregnant, it's important to get in touch with a midwife or doctor to start your pregnancy (antenatal) care.

You can do this by contacting:

Things to think about

In the early days and weeks of pregnancy, you may not know if you're pregnant.

But you can do the following things:

  • take a folic acid supplement of 400 micrograms a day while you're trying to get pregnant and until the 12th week of pregnancy
  • take a vitamin D supplement of 10 micrograms a day
  • avoid some foods to protect against infections
  • stopping smoking is one of the best things you can do for your baby's health

You can get supplements from pharmacies and supermarkets, or your GP may be able to prescribe them for you.

If you want to get your vitamin D or folic acid from a multivitamin tablet, make sure the tablet does not contain vitamin A (or retinol).

Your baby at 4 weeks

In weeks 4 to 5 of early pregnancy, the embryo grows and develops within the lining of your womb.

The outer cells reach out to form links?with your blood supply.?The inner cells form into 2, and then later into 3 layers.

Each of these layers will grow to be different parts of your baby's body:

  • the inner layer becomes the breathing and digestive systems, including the lungs, stomach, gut and bladder
  • the middle layer becomes the heart, blood vessels, muscles and bones
  • the outer layer becomes the brain and nervous system, the eye lenses, tooth enamel, skin and nails

In these early weeks of pregnancy, the embryo is attached to a tiny yolk sac that provides nourishment.

A few weeks later, the placenta will be fully formed and take over the transfer of nutrients to the embryo.

The embryo is surrounded by fluid inside the amniotic sac. It's the outer layer of this sac that develops into the placenta.

Cells from the placenta grow deep into the wall of the womb, establishing a rich blood supply. This ensures the baby receives all the oxygen and nutrients it needs.

You at 4 weeks

Conception usually takes place about 2 weeks after your last period, around the time you release an egg (ovulate).

In the first 4 weeks of pregnancy, you probably will not notice any symptoms.

The first thing you may notice is that your period does not arrive, or you may have other signs and symptoms of pregnancy, such as breast tenderness.

You can confirm the pregnancy with a pregnancy test.

Your baby at 5 weeks

Your baby's nervous system is already developing, and the foundations for its major organs are in place. At this stage, the embryo is around 2mm long.

The heart is forming as a simple tube-like structure. Your baby already has some of its own blood vessels and blood begins to circulate.

A string of these blood vessels connects you to your baby and will become the umbilical cord.

At the same time, the?embryo's outer layer of cells develops a groove and folds to form a hollow tube called the neural tube. This will become your baby's brain and spinal cord.

Defects in one end (the "tail end") of the neural tube lead to?spina bifida. Defects?in the "head end" lead to anencephaly, when the bones of the skull do not form properly.

Folic acid prevents spina bifida. You should start taking it as soon as you find out you're pregnant (even before you get pregnant, if possible).

You at 5 weeks

This is the time of the first missed period, when most women are only just beginning to think they may be pregnant.?

Antenatal care (also called pregnancy or maternity care) is the care you get from midwives and doctors during your pregnancy to make sure you and your baby are as well as possible.

Contact your GP surgery or your preferred maternity service promptly once you know you're pregnant, so you start getting care at the right time. They'll arrange your first midwife appointment.

Starting your maternity care early in pregnancy is important if you have a health condition that may affect your pregnancy, such as heart or lung conditions, epilepsy, mental health problems, diabetes or asthma.

Your doctor or midwife will be able to advise you if you're taking medicines for your condition while you're pregnant, and provide the specialist care you and your baby need.

Do not stop taking any prescribed medicine without checking with your doctor or midwife first.

Things to think about

  • You're advised to take 400 micrograms of folic acid a day while you're trying to get pregnant and until the 12th week of pregnancy.
  • Stopping smoking is one of the best things you can do for your baby's health.
  • Avoid some foods in pregnancy to protect against infections.
  • You can make a to-do list to keep track of things to do, such as taking folic acid and getting free dental care.
  • Talk to your midwife, doctor or pharmacist before taking any medicines, or any herbal or homeopathic remedies.

Your baby at 6 weeks

By the time you're 6 to 7 weeks pregnant, there's a large bulge where the heart is and a bump at the head end of the neural tube.?This bump will become the brain and head.

The embryo is curved and has a tail, and looks a bit like a small tadpole. The heart can sometimes be seen beating on a vaginal?ultrasound scan?at this stage.

The developing arms and legs become visible as small swellings (limb buds). Little dimples on the side of the head will become the ears, and there are thickenings where the eyes will be.

By now, the embryo is covered with a thin layer of see-through skin.

You at 6 weeks

It's normal to feel a range of emotions in pregnancy and everyone's experience is different.

A healthy diet in pregnancy, having foods that are nutritious and safe to eat, is important for the wellbeing of you and your baby.

Stopping smoking when you're pregnant is one of the most important things you can do for your baby's wellbeing.

Ask your midwife, GP or pharmacist for advice and the details of your nearest NHS stop smoking service.

Your baby at 7 weeks

By?7 weeks, the embryo has grown to about 10mm long from head to bottom. This measurement is called the crown-rump length.

The brain is growing rapidly and this results in the head growing faster than the rest of the body.?The embryo has a large forehead, and the eyes and ears continue to develop.

The inner ears start to develop, but the outer ears on the sides of the head will not appear for a couple more weeks.

The limb buds start to form cartilage, which will develop into the bones of the legs and arms. The arm buds get longer and the ends flatten out – these will become the hands.

Nerve cells continue to multiply and develop as the brain and spinal cord (the nervous system) starts to take shape.

You at 7 weeks

Your womb has grown to the size of a lemon by the time you're around 7 or 8 weeks pregnant.

You're probably feeling tired. Your breasts might feel sore and enlarged, and you may need to?pee more often than usual.

You may start to feel sick or tired, or have other minor pregnancy problems for a few weeks around this time.

In most cases,?feelings of nausea and vomiting (morning sickness) start to improve after around 14 weeks of pregnancy.

Some infections can harm a pregnancy. It's important to let your doctor or midwife know if you think you may have an infection so they can give you the right care as early as possible.

You may have bleeding or sore gums when you're pregnant. Good mouth hygiene and regular dental care, to keep your teeth and gums as healthy as possible, is the best way to avoid or care for gum problems.

Dental care is free during pregnancy and until 1 year after your due date. Ask your midwife or doctor about how to apply for free dental care.

Your baby at 8 weeks

By the time you're 8 weeks pregnant, your baby is called a foetus, which means offspring.

The legs are getting longer. The different parts of the leg are not properly distinct yet. It'll be a bit longer before the knees, ankles, thighs and toes develop.

The foetus is still inside its amniotic sac and the placenta is continuing to develop, forming structures that help attach the placenta to the wall of the womb.

At this stage, the foetus still gets its nourishment from the yolk sac.

You at 8 weeks

Your womb has grown to the size of a lemon by the time you're around 7 or 8 weeks pregnant.

You're probably feeling tired. Your breasts might feel sore and enlarged, and you're probably needing to pee more often than usual.

You'll probably have missed your second period. But you may experience a little bleeding in pregnancy from your vagina.

Always mention any bleeding in pregnancy to your midwife or GP, particularly if it continues and you get stomach pain.

You can find more information on pregnancy in the 'Your Pregnancy and Birth book'.

Last Updated: 21/07/2023 10:54:35
The information on this page has been adapted by NHS Wales from original content supplied by NHS UK NHS website