Early pregnancy symptoms: the first signs of pregnancy

If you might be pregnant and you have bleeding or pain, do not wait to see whether other symptoms follow. The NHS treats bleeding in pregnancy as an emergency when it comes with severe abdominal pain, pain in the shoulder, or feeling sick, faint or dizzy, and when it is heavy enough to soak a period pad soon after you put it on (NHS, "Vaginal bleeding in pregnancy", 2026). In the UK, call the emergency number or go to A&E, the hospital emergency department; in the US, call the emergency number or go to the nearest emergency room. The box above shows the emergency and urgent numbers for where you are, and get help now lists the other symptoms that need checking straight away.

When do pregnancy symptoms start? Usually at 4 to 6 weeks

When do pregnancy symptoms start? The NHS says symptoms and early signs of pregnancy usually start when you are around 4 to 6 weeks pregnant, and that not everyone has all of them (NHS, "Signs and symptoms that might mean you're pregnant", 2026). Those weeks are counted the way doctors and midwives count a pregnancy, from the first day of the last period, so about two of them come before the pregnancy has begun (ACOG, "How Your Fetus Grows During Pregnancy", 2024). On a 28-day cycle a period is due 28 days after the last one began, which is 4 weeks on that count. When pregnancy symptoms start, on the NHS figure, is therefore around the time a period is missed or in the two weeks after it. That last step is our arithmetic, and a longer or shorter cycle moves it.

One study measured when pregnancy symptoms start rather than describing it. Sayle and colleagues asked 221 women who were trying to conceive to keep a daily record of symptoms. Among the 136 who went on to have a live birth, half had symptoms by day 36 after their last period, and 89 in 100 had them by the end of the eighth week (Sayle et al., 2002). Day 36 is 5 weeks and 1 day on the usual count, again our arithmetic. How long does it take for pregnancy symptoms to show, then? It varies a good deal: in that study the other 11 in 100 had recorded none by the end of week 8.

How soon do pregnancy symptoms start at the earliest, and how early can pregnancy symptoms start? None of the sources cited here describes very early pregnancy symptoms before the pregnancy hormone hCG is being made. The NHS says hCG starts to be produced around 6 days after fertilization (NHS, "Doing a pregnancy test", 2022), and in a study that tested urine every day it first appeared 6 to 12 days after ovulation (Wilcox et al., 1999). When do you start feeling pregnancy symptoms? That differs from one person to the next, and the weekly guides for 4 weeks pregnant, 5 weeks pregnant and 6 weeks pregnant set out what the NHS describes at each of those weeks.

The early signs of pregnancy the NHS lists

The NHS lists twelve early signs of pregnancy (NHS, "Signs and symptoms that might mean you're pregnant", 2026). Mayo Clinic, a US academic medical center, gives a similar list in two parts, the classic signs and the less obvious ones (Mayo Clinic, 2024). The table sets the two side by side, in the NHS's order, with the signs only Mayo Clinic lists at the end. Neither source says that any one sign means you are pregnant, and all of these signs of pregnancy can have other causes.

MedlinePlus, from the US National Library of Medicine, gives a shorter list of common symptoms of pregnancy: a missed period, which it calls the most common sign, swollen and tender breasts, tiredness, needing to pee more often, nausea and vomiting, and feeling bloated (MedlinePlus, "Pregnancy Test", 2026). The symptoms of early pregnancy, or signs of early pregnancy, are much the same on all three lists. What differs is how much each source says about them.

Early signs of pregnancy: discharge

The NHS includes more vaginal discharge among the early signs of pregnancy and qualifies it: discharge without any soreness or irritation (NHS, "Signs and symptoms that might mean you're pregnant", 2026). On its page about stomach pain in pregnancy, the NHS advises calling your maternity unit straight away if you have stomach pain together with vaginal discharge that is unusual for you, or fluid leaking from the vagina (NHS, "Stomach pain in pregnancy", 2024). Mayo Clinic's list does not mention discharge.

Less common signs

Uncommon early pregnancy symptoms, or weird early pregnancy symptoms as they are often searched, usually mean the ones that surprise people: a metallic taste, a new sensitivity to smells, cravings, going off foods you usually enjoy, and a blocked or runny nose. The first four are on the NHS list (NHS, "Signs and symptoms that might mean you're pregnant", 2026). Mayo Clinic explains the blocked nose as rising hormone levels and blood production making the lining of the nose swell, dry out and bleed easily (Mayo Clinic, 2024). Neither source says how many people have any of them.

Which signs come first

For most people, the first signs of pregnancy start with the period. MedlinePlus calls a missed period the most common sign of early pregnancy (MedlinePlus, "Pregnancy Test", 2026), and Mayo Clinic puts it first among the classic signs (Mayo Clinic, 2024). The one sign the NHS places around the time a period is due, rather than after it, is light bleeding or spotting (NHS, "Signs and symptoms that might mean you're pregnant", 2026), and Mayo Clinic says light spotting might be one of the first signs of pregnancy (Mayo Clinic, 2024).

The earliest signs of pregnancy

Beyond those two, none of the sources cited here ranks the earliest signs of pregnancy in order. The Sayle study reports when symptoms began, not which one came first (Sayle et al., 2002), and the NHS says not everyone has every symptom. Mayo Clinic notes that some people feel sick before the usual one to two months and some never do (Mayo Clinic, 2024). A list that puts the signs in a fixed order for everyone goes further than this evidence.

Signs before a missed period

Early signs of pregnancy before a missed period are limited by timing. Implantation, when the pregnancy attaches to the lining of the uterus, comes first, and Wilcox and colleagues took the first appearance of hCG in urine as its marker: 6 to 12 days after ovulation, and on day 8, 9 or 10 in 84 in 100 of the pregnancies that lasted at least six weeks (Wilcox et al., 1999). ACOG's guidance on due dates assumes ovulation on day 14 of a 28-day cycle (ACOG Committee Opinion 700, 2017), so on that cycle hCG first appears on about day 20 to 26, a few days before the period is due. That is our arithmetic, and it moves with the length of your cycle. When does implantation occur sets out the timing in more detail.

Of the signs the NHS lists, light spotting around the time the period is due is the one it places before a period is missed (NHS, "Signs and symptoms that might mean you're pregnant", 2026). Signs of pregnancy before a missed period, and early pregnancy symptoms before a missed period, are also hard to read because they overlap with the days before a period: the NHS compares sore breasts in early pregnancy with the way breasts can feel before a period, and Mayo Clinic says many early pregnancy symptoms are not unique to pregnancy and some can mean a period is about to start (Mayo Clinic, 2024). A test is the way to find out. The NHS says most tests work from the first day of a missed period, or at least 21 days after unprotected sex if you do not know when your period is due (NHS, "Doing a pregnancy test", 2022). The pregnancy test calculator works out those dates from your ovulation date or last period.

Very early signs of pregnancy at 1 week or 2 weeks

Searches for very early signs of pregnancy at 1 week, or early pregnancy symptoms at 2 weeks, run into the way pregnancy is counted. ACOG counts a pregnancy from the first day of the last period, so about two of the 40 weeks come before the pregnancy has begun (ACOG, "How Your Fetus Grows During Pregnancy", 2024). At "1 week pregnant" on that count you are having your period, and on a 28-day cycle ovulation falls at the end of week 2 (ACOG Committee Opinion 700, 2017). Symptoms of pregnancy cannot come from a pregnancy that has not yet started.

If "1 week" means one week after sex, the timing above still applies: in the Wilcox study the hormone first appeared 6 to 12 days after ovulation, and in the Sayle study half of the women with live births had symptoms by day 36 after their last period. None of the sources cited here describes symptoms in the first week after conception. This site's week-by-week guide starts at 4 weeks pregnant.

Early pregnancy or a period on the way?

Signs of period vs pregnancy overlap, and the sources say so plainly. Mayo Clinic says many early signs of pregnancy are not unique to pregnancy, that some can mean you are getting ill or that your period is about to start, and that you can be pregnant without many of them (Mayo Clinic, 2024). The NHS compares the breast changes of early pregnancy with the way breasts can feel before a period (NHS, "Signs and symptoms that might mean you're pregnant", 2026). None of the sources cited here gives a way to tell early pregnancy symptoms vs PMS apart by how they feel, and the same is true of early pregnancy vs period symptoms such as cramps or bloating.

A pregnancy test is how to find out. How soon can you take a pregnancy test explains when a result is reliable, and if cramps are the question, cramping in early pregnancy covers how the NHS describes them.

Symptoms that need help straight away

The NHS says some symptoms may be a sign of something more serious, and names vaginal bleeding, stomach pain and pelvic pain. It advises getting medical advice if you are worried about your health or your baby's at any time (NHS, "Signs and symptoms that might mean you're pregnant", 2026). For bleeding, it gives two levels of urgency. Get urgent help, through your maternity unit, an early pregnancy unit if you are under 20 weeks, or the NHS urgent advice line, for light bleeding or spotting with no pain or mild tummy pain, or with diarrhea, or pain or pressure when you pee or poo. Call the emergency number for bleeding with severe tummy pain, pain in the shoulder, feeling sick, faint or dizzy, or bleeding that soaks a period pad soon after you put it on (NHS, "Vaginal bleeding in pregnancy", 2026).

For stomach pain, the NHS advises calling your maternity unit straight away if it comes with bleeding or spotting, regular cramping or tightenings, lower back pain, unusual discharge, pain when you pee, or cloudy, pink, red or brown pee, or if the pain is severe or does not go away after 30 to 60 minutes of rest (NHS, "Stomach pain in pregnancy", 2024). In the US, ACOG advises contacting your ob-gyn if you have any bleeding at any time during pregnancy (ACOG, "Bleeding During Pregnancy", 2021).

Spotting during pregnancy and cramping in early pregnancy go through each in more detail, and bleeding in early pregnancy lists who to contact where you are.

What to do next

If you think you might be pregnant, the NHS advises doing a pregnancy test, and says you can buy one or may be able to get one free from your GP or a sexual health service (NHS, "Signs and symptoms that might mean you're pregnant", 2026). A positive result is almost certainly correct, and a negative result is less reliable, most often because the test was taken too early (NHS, "Doing a pregnancy test", 2022). Faint positive pregnancy test explains what a light second line can and cannot tell you.

After a positive test, the NHS advises telling NHS maternity services as soon as possible by referring yourself for pregnancy care with a midwife (NHS, "Doing a pregnancy test", 2022). Mayo Clinic advises making an appointment with your health care provider, so that prenatal care can begin (Mayo Clinic, 2024). The due date calculator works out a due date from the first day of your last period, and the week-by-week guide from 5 weeks pregnant onward follows what changes.

This guide is information, not a diagnosis or a recommendation of treatment, and it is no substitute for your own clinician. See the medical disclaimer.