Pregnancy calendar - your week-by-week guide to the stages of pregnancy

We've got all the information you need about your body, your emotions and your baby, week-by-week of your pregnancy.

Find out about the stages of your pregnancy

  • Weeks 1-12 infographic

    First trimester: weeks 1 to 12

    You're pregnant: congratulations! The first weeks of your pregnancy are a vital time as your body gets busy building a baby. How exciting!

  • weeks 13 - 28 infographic

    Second trimester: weeks 13 to 28

    The second trimester is the middle three months of your pregnancy. This is a time when lots of women tell the world they’re pregnant and begin to feel like the pregnancy is more ‘real’.

  • week 29-40 infographic

    Third trimester: weeks 29 to 40

    The end of your pregnancy is in sight. It won't be long until your baby arrives. Feelings at this stage of pregnancy tend to vary from tiredness and worry to excitement about the baby.

What is a trimester?

People often talk about pregnancy as being nine months long. In fact it’s usually slightly longer than this. Your pregnancy is measured from the first day of your last period rather than the day you actually conceived.

A pregnancy generally lasts around 40 weeks, and your dates are referred to in weeks because this is more accurate than talking in months.

Your pregnancy has three phases, called trimesters, and each trimester is about three months long.

Each trimester has its own mix of highs and lows, and you can find out what to expect in this pregnancy calendar. The information in the calendar may be helpful for the people close to you as well.

Confused about pregnancy weeks? Wondering whether to count from the day you conceived or your last period? Discover how to count your pregnancy in weeks and months on the BabyCentre website. You can also join your BabyCentre birth club to meet others due at the same time as you, share stories, and swap tips and advice.

Follow Tommy's PregnancyHub on Instagram

Read more

  • Pregnant woman looking anxious.

    Mental health before, during and after pregnancy

    Although it’s normal to have periods of worry and stress when you’re pregnant, some women have feelings that don’t go away and this can be a sign of something more serious.

  • Pregnant woman exercising on cross-trainer.

    Exercise and activity in pregnancy

    People may tell you that pregnancy is a good time to put your feet up. If your pregnancy is uncomplicated it is actually much healthier for you and your baby to exercise while pregnant.

  • Woman on treadmill at gym.

    Weight management in pregnancy

    Although you will be putting on weight in pregnancy as your baby grows, limiting the amount of extra weight gain in pregnancy will improve your health and your baby's, both now and in the future.

  • Mother and newborn baby.

    Labour & birth

    Most women worry about how they will cope with the pain of labour and birth. You may worry too, especially if it is your first baby and you do not know what to expect.

  • Woman in hospital bed being comforted by health professional.

    Pregnancy complications

    Sometimes things go wrong during pregnancy and you need extra care

  • Pregnant woman with sharp pain in her stomach.

    Is it serious? Pregnancy symptom checker

    In many cases the symptoms in this section can be treated easily and will not lead to a serious complication. But sometimes they are signs of something more serious.


1. NHS Choices [accessed 2 February 2015] “Your pregnancy week by week”

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    Last reviewed on April 1st, 2014. Next review date April 1st, 2017.

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    Please note that these comments are monitored but not answered by Tommy’s. Please call your GP or maternity unit if you have concerns about your health or your baby’s health.
    • By Helen (not verified) on 19 Apr 2020 - 07:38

      My last period date was 13th March 2020, please how many weeks pregnant am I? Please reply. Thanks

    • By Justin (not verified) on 3 Apr 2020 - 13:17

      When would the conception date have been if my first day of last period started February 23 and ended February 29 and I tested positive on a pregnancy test April 2.

    • By Opeyemi (not verified) on 22 Jan 2020 - 10:50

      Hello Tommy, pls i will like to know my due date. Test revealed i was 8 weeks and 5 days pregnant on the 26th of October 2018.
      I will appreciate soonest feedback.

    • By Zanele (not verified) on 8 Jan 2020 - 17:32

      It is normal for my baby weigh is 23cm for 30 weeks??

    • By Amara (not verified) on 4 Dec 2019 - 11:48

      My last period was 2 March many week's I m now???plzzz tell

    • By Rebecca (not verified) on 15 Oct 2019 - 09:01

      I’m 9wks 5 days and my nausea and breast tenderness have eased off significantly, I’m due a scan in 6 days but worried that I may have a missed miscarriage. I have seen the baby and the heartbeat was strong but I’ve read that symptoms usually peak at 9 weeks?

    • By Nunu (not verified) on 25 Jul 2019 - 13:58

      26October 2018 was my first of my last period how many weeks do i have now

    • By Halima (not verified) on 14 Jul 2019 - 11:34

      Pls i want to know if camping is normal in 8weeks pregnancy

    • By Rita (not verified) on 5 Jul 2019 - 22:55

      My last period was 24 may, I want to no my week calendar date. Thank you

    • By Favour (not verified) on 15 Jun 2019 - 12:55

      Plz have been noticing my period pain but no period yet but I'm not experiencing any form of pregnancy symptoms

    • By Jane (not verified) on 31 Jan 2019 - 09:52

      my last period was 11dec2018. how many weeks am i now.

    • By Midwife @Tommys on 31 Jan 2019 - 10:42

      Hi Jane - Thank you for your message.
      If the first day of your last period was 11/12/2018 and you have regular 28 day cycle, your babies due date is estimated around 18th September 2019.

    • By mxo (not verified) on 26 Jan 2019 - 11:53

      I got my last period on date3/9/2018and now we are on date 26/1/2019 now I must wonder how many month a my plz

    • By Midwife @Tommys on 29 Jan 2019 - 13:54

      Hi mxo - using your last period dateof 3/9/2018 - you are approx. 21 weeks pregnant today. With an estimated due date of around 11th June.
      Congratulations - all the best. Tommy's Midwife

    • By blossom (not verified) on 18 Jan 2019 - 15:34

      Am nt sure how far I am

    • By Midwife @Tommys on 21 Jan 2019 - 16:40

      Hi Blossom
      You are approximately 8 weeks and 4 days gestation with an estimated due date of 29th August 2019. Please contact your local maternity unit as soon as possible so that you can start your antenatal care.
      Take care
      Tommy's Midwife

    • By DL (not verified) on 7 Jan 2019 - 19:46

      The first day of my last period is 31 October 2018 so how far is my pregnancy please help

    • By Midwife @Tommys on 8 Jan 2019 - 14:21

      Hi - If you have regular 28 cycle, you would be around 10 weeks pregnant today with an estimated due date of 06/08/2019.
      You can find more information on how dates are calculated in the link below:

    • By Nicole Watkins (not verified) on 21 Mar 2019 - 22:11

      Hi i need help I done a pregnancy test it come up positive and then I done another in the night so what does that mean and I have really sore nipples could i be pregnant because my nipples are really sore I need help my last period was 1st of March

    • By Irena (not verified) on 30 Oct 2019 - 16:06

      I want to get pregnant

    • By Amanda (not verified) on 28 Nov 2018 - 06:57

      I need help 7 weeks so scared im anxious all the time, i can't sleep. Ive had a stillborn in the past and i had sinus tach now im scared its happening again. I want my child but i feel like i don't wont to be pregnant. I don't know what to do i feel more anxious, depressed, i feel like i cant handle it or im going crazy! Please help.

    • By Midwife @Tommys on 29 Nov 2018 - 11:38

      Hi Amanda. Thank you for comment. I am sorry to hear of your previous experience. Everything you are feeling is completely normal but it maybe worth discussing things with your midwife or GP. If you wish, you can also email us at [email protected] or call us on 0800 0147 800 where we can discuss things in more detail.
      I hope this helps. Best Wishes Tommy's Midwives.

    • By ellehere (not verified) on 27 Sep 2018 - 08:16


      Am new and my husband are trying to start our family, for last few months I have started tracking my dates..and tracking when I start ovulating... As per whattoexpect- Many women use ovulation predictor kits, which identify the date of ovulation 12 to 24 hours in advance by looking at levels of luteinizing hormone, or LH, the last of the hormones to hit its peak before ovulation.
      Is any one using predictor kit ??? Any other way to know best ovulation time??

    • By Midwife @Tommys on 28 Sep 2018 - 12:09

      Hi - thank you for your message.

      Ovulation usually happens about 10 to 16 days before the start of your next period, so it helps to know your cycle length before you start trying to conceive.

      You may never have considered when you might ovulate within your cycle, and if you have been using a hormone contraceptive such as the Pill, you won’t have had a natural menstrual cycle for a while.

      As a first step, mark on your ovulation calendar the dates that you bleed during a period. You can then count how many days from the first day of your period to your next period to work out the length of your cycle.

      Cervical mucus changes
      The cervix secretes mucus throughout the menstrual cycle, starting off sticky white and gradually becoming thinner and clearer.

      Before and during ovulation the mucus increases and becomes much thinner, slippery and stretchy. Women often compare it to raw egg white.

      This thinner mucus is designed to help the sperm swim easily through it. It indicates that you are in your fertile phase, so this is the time to have sex if you want to get pregnant, but use contraception if you do not!

      The last day you notice the wetter secretions is sometimes known as ‘peak day’ and for most women this occurs very close to the time of ovulation.

      You can also find out about your menstrual cycle by keeping a note of your temperature each morning when you wake up. Your temperature rises by about 0.2°C when ovulation has taken place.

      As it is only an indicator that you have ovulated, and doesn’t tell you when your fertile time starts, this is not very useful for most women.

    • By Hannah green (not verified) on 26 Sep 2018 - 17:41

      I had a scan on the 18/09/18 and was told im 6 weeks pregnant (7 weeks now) but they never told me my due date? My last period was the 28/07/18 so i thought i was 7 weeks at my scan but the fetus only measured 3.2mm with heartbeat. Is that normal also?

    • By Midwife @Tommys on 27 Sep 2018 - 10:29

      Hi Hannah, Thank you for your comment.

      If the first day of your last period was on the 28th July then your due date should be around the 4th May 2019. It can be normal for your dates to be out by a few days, this will all depend on when you ovulated, but your dates do add up correctly. When you have your 12 week scan, they will give your actual due date via scan as this is when it is the most reliable. Hope this helps, Take Care, Tommy's Midwives x

    • By Mavis (not verified) on 21 Mar 2018 - 12:36

      29th of December 2017 was my last date of periods.l had sex only on the 8th January 2018, l found out beginning of March that lm pregnant . How old is my pregnancy

    • By Midwife @Tommys on 22 Mar 2018 - 14:52

      Hi Mavis, Thank you for your comment and congratulations on your pregnancy.

      If the 29th December was the first day of your last period then your due date would be around the 4th October. This would make you around 7 weeks and 5 days today. Hope this helps, take care Tommy's Midwives x

    • By Millicent (not verified) on 25 Sep 2018 - 15:11

      I got period on 02/08/2018.i notice am pregnant, please how many weeks

    • By Midwife @Tommys on 26 Sep 2018 - 11:21

      Hi Millicent
      Using the date you gave of 8th aug as the first day of your last menstrual period, assuming you have a 28 day cycle, you are approx 8 weeks pregnant today.
      You need to go to your GP to start your antenatal care with a midwife and arrange for your first scan.
      Congratulations. All the best
      Tommy's Midwife

    • By joy (not verified) on 2 Mar 2018 - 16:59

      i was suppose to see my mens on 30-31 of feb 2018 but it did not come out then on 11 of feb i had a hcg home urine test tested positive i have all the sign to show i can be pregnant but i have not done blood test but do you tink am having a baby or should i do blood test.

    • By Midwife @Tommys on 5 Mar 2018 - 13:00

      Hi Joy,
      From your message I am unsure when your took your pregnancy test, if it was after your bleeding then this is fine and a home urine test is all you need to test for a pregnancy and I would advise for you to see your GP and arrange for a referral to maternity care. If the test was prior to bleeding then I would advise for you to re take the test to confirm if you are pregnant. If you are not already then we would strongly advise for you to be taking a daily folic acid supplement. Best wishes, Tommy's midwives

    • By mellisa (not verified) on 20 Mar 2018 - 12:46

      hi joy,

      if you are doubtful of the pregnancy test then have yourself checked by an OB Gyne. In this way, you can ensure that you are really having a baby or not.


    • By Anonymous (not verified) on 14 Nov 2017 - 09:53

      The first day of my last period was 2nd of october so im only about 6weeks pregnant but im worried that wearing a tight pair of jeans could harm my unborn baby, does anyone know if it could? And if not the what could harm my baby?

    • By Midwife @Tommys on 15 Nov 2017 - 11:05

      Hi, Thank you for your comment.

      Wearing skinny jeans wont harm your baby. Your baby at this stage is very low down in your pelvis, well protected in the uterus. As your pregnancy progresses, you may want to wear looser fitting clothes so that you can feel more comfortable.
      There are a few things to avoid in pregnancy that could cause potential harm to your baby but please don't be alarmed, please go to the following link for more information about what to avoid in pregnancy, this will give your a straight forward helpful guide that will make it easy for you to follow:

      There are also certain medications that you should avoid in pregnancy like ibuprofen but if you do need pain relief for a headache then you can take the occasional paracetomol as long as you don't exceed the recommended dosage. If you have any concerns, then you can always speak to your GP or midwife. If you need any further advice or support then please contact the Tommy's midwives on [email protected] or call us Monday to Friday 9am-5pm 0800 0147 800. Hope this helps, take care, Tommy's Midwives x

    • By amy (not verified) on 7 Sep 2017 - 07:57

      I did a home pregency test on the 14thJuly I did another test two wks ago and it came back positive I slept with Someone on the 2nd of August and again on the 6th of august would I be pregnant to his person can u fall pregnant that soon afta the first test on July 14th was negative

    • By Midwife @Tommys on 7 Sep 2017 - 09:49

      Thank you for your comment.
      You can fall pregnant after a negative test depending on your monthly cycle.
      Have you had a period since your 1st pregnancy test in July? If so, then it's likely you conceived after you had sex in August and would be pregnant to this person
      Pregnancy tests measure levels of pregnancy hormones in your urine; these levels increase very quickly at the start of the pregnancy-If you haven't had a period since your Ist pregnancy test then the levels may have increased enough to give the positive result you had 2 weeks ago.
      Please see your GP or contact your local maternity unit so that you can have your dating scan which will confirm how many weeks pregnant you are ( and therefore when you conceived) and start your pregnancy care.
      I have attached 2 links that you may find helpful
      Hope this helps
      Tommy's Midwife

    • By Annet (not verified) on 25 Aug 2017 - 03:20

      How many weeks am I my last period date was 26 Nov 2016

    • By Midwife @Tommys on 25 Aug 2017 - 16:52

      Hi, you EDD will be on your scan which you would have had at about 12 weeks pregnant. If you did not have your scan then the first one you had will give you your due date. The scan EDD is what is used in your pregnancy, your period dates are only used as an estimation at the beginning of your pregnancy. It can also be affected by the length of your cycle too.

    • By anonymous (not verified) on 20 Aug 2017 - 20:34

      what can happen to an unborn baby if the father is a heavy drug taker, and i have drank alcohol in the first 4 weeks of pregnancy, as i didnt know i was pregnant?

    • By Midwife @Tommys on 23 Aug 2017 - 16:07

      Hi, thank you for your message it is a difficult question to answer in regards to your partner but many women unaware that they are pregnant do drink and take drugs before realising.
      If you have stopped drinking now this is good news for your pregnancy. If you would like more information or need help to stop drinking Talk to Frank is a good place to start.
      We are also here to talk on 0800 0147 800 in confidence.
      Warm wishes
      Anna -Tommy's Midwife

    • By Anonymous (not verified) on 4 Aug 2017 - 17:57

      My last period was june 22nd and my doctor says I'm a maximum of 6 weeks so my due date is between 25-29th March. When would I have conceived?

    • By Midwife @Tommys on 7 Aug 2017 - 11:23

      If you have a normal length regular cycle you would have conceived between the 2nd and 9th July. Your scan at 12 weeks will confirm your dates.

    • By Kimberley (not verified) on 5 Jul 2017 - 14:35

      Hi I had my period on the 17th of may came off the pill on the 21st bled again on the 4th of june and just got a positive pregnancy test any idea when I conceived?

    • By Midwife @Tommys on 6 Jul 2017 - 13:27

      Hi Kimberly, we can never be really sure about the time of conception as sperm can live in the body for up to 7 days. Normally midwives date a pregnancy from the first day of your last period, which would be 4th June, women tend to ovulate around 14 days after this, so it could be possible that conception occurred around this time but again we can never be sure of the actual time of conception. If you have had a positive pregnancy test and you are unsure of your dates then please see your GP who may be able to refer you for an early scan to see how many weeks you are into your pregnancy. Hope this helps, Best Wishes Tommy's Midwives x

    • By Kenesia (not verified) on 29 Jun 2017 - 20:50

      My last period was on the 15th of may 2017 . I had a etopic pregnancy and lost a tube last june 2016 at 5 weeks so im so scared to do a test just hoping this baby will stay im praying it will all go well

    • By Midwife @Tommys on 30 Jun 2017 - 10:00

      Hi, it is totally understandable that you are feeling anxious in this pregnancy and these early weeks are scary for you. According to your dates, if you have a regular cycle then you are about 6+3 weeks pregnant. It is important that you are taking your folic acid supplement and any concerns please see a GP or go to A+E straight away. I am sure you are aware of what to look out for but here is a link to our info if this helps at all: Take care, Tommy's midwives x

    • By caroline mcclean (not verified) on 15 Aug 2017 - 21:09

      i had my period on the 28th of may and i have not seen one since

    • By Midwife @Tommys on 16 Aug 2017 - 09:00

      Hi Caroline. If you have not had a period since 28th May and have done a pregnancy test and it is negative, then it would be sensible to book to see your GP who will likely refer you onto a gynecology specialist doctor. If you have a positive pregnancy test, then you also need to either make an urgent GP appointment or contact your local midwives (you can google your nearest hospital and find a contact number or email for the midwives and access maternity care that way too.)If you have any further issues you would like to discuss, feel free to email or call us, we would be happy to help. All the best

    • By Anonymous (not verified) on 11 Jun 2017 - 21:00

      Hi i need help I am 24 weeks pregnant wen did I conicved. On the 10th dec I had sex with someone thn on the 8th of Jan had sex with someone else. My dun date is on the 30th sec plz help

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