# First Trimester Guide UK — Symptoms, Dates & Early Help | Clever Mum > Everything the first trimester throws at you — dating the pregnancy, sickness and fatigue, bleeding worries, appointments, and what to do (and avoid) in weeks * [ Home ](/) * › [ Pregnancy ](/pregnancy/) * › The First Trimester Survival Guide: Symptoms, Dates and What Comes When Pregnancy # The First Trimester Survival Guide: Symptoms, Dates and What Comes When [ EW ](/authors/emma-whitfield/) By [ Emma Whitfield ](/authors/emma-whitfield/) · Pregnancy & Baby Writer Published 13 July 2026 Quick answer — When should I see a midwife after a positive test? The first trimester runs to the end of week 12, counted from your last period — not conception. Priorities: 400mcg folic acid daily, book your midwife appointment as soon as the test is positive, expect nausea and profound fatigue to peak around weeks 8–10, know that light spotting is common but bleeding is always worth reporting, and hold on: for most people it genuinely lifts by weeks 12–16. Who should skip this Skip this if you are past 12 weeks — use the trimester to-do list. Skip it if you have severe pain or bleeding; call your early pregnancy unit. The strange secret of the first trimester is that its hardest weeks are usually invisible: no bump, no announcement, often nobody at work knowing — while inside, you're building an entire placenta on a nausea budget. Here's the survival map for weeks 4 to 13. ## How is my pregnancy dated — and when is my due date? **Pregnancy is counted from the first day of your last menstrual period (LMP) — so "4 weeks pregnant" describes roughly 2 weeks after conception, and a due date lands 40 weeks from LMP, adjusted for your cycle length. The 11–14 week dating scan then sets the official version from the baby's measurements.** If you're tracking backwards from ovulation — perhaps you were using [an ovulation calculator](https://worldcalculators.org/calculators/ovulation/) while trying to conceive — the arithmetic makes sense: conception happens around cycle day 14 of a 28-day cycle, so LMP-dating adds those two weeks to everything. For the forward version, our [due date calculator](/tools/due-date-calculator) maps your weeks and trimester dates (there's also a quick [pregnancy due date tool at WorldCalculators](https://worldcalculators.org/calculators/pregnancy-due-date/) if you want a second opinion on the maths) — and once you have your week number, our [week-by-week hub](/pregnancy/week) tells you exactly what's happening in each one. Just hold every calculated date loosely until the dating scan: only around 1 in 20 babies arrives on the day itself. ## Why do I feel so sick and exhausted? **Blame the hormones doing the building work: hCG (the pregnancy hormone) climbs steeply to a peak around weeks 8–10 — precisely when nausea peaks — while progesterone drives the bone-deep fatigue. Both typically ease markedly between weeks 12 and 16. "Morning" sickness is a lie: any-time-of-day sickness affects around 8 in 10 pregnancies.** What genuinely helps, per NHS guidance and hard-won experience: eating little and often (an empty stomach is nausea's best friend — plain crackers before getting out of bed is a cliché because it works), cold and bland over hot and fragrant, ginger and acupressure bands for some, and treating the fatigue as a medical instruction rather than a character flaw — the placenta finishes its heavy construction around week 12, which is precisely when energy returns. The escalation line: if you can't keep fluids down for 24 hours, are losing weight or feel faint, that's hyperemesis territory — same-day GP or midwife contact, because [severe pregnancy sickness](https://healthanswers.co.uk/) is a recognised condition with safe, effective treatment, not something to white-knuckle. ## Is bleeding in early pregnancy always bad news? **No — light spotting affects roughly 1 in 4 early pregnancies and often comes to nothing: implantation bleeding, cervical sensitivity after sex, or hormonal spotting around missed-period dates. But all bleeding in pregnancy warrants a same-day call to your GP, midwife or 111 — and bleeding with one-sided pain or shoulder-tip pain needs urgent review to rule out ectopic pregnancy.** The honest framing: early pregnancy loss is common — around 1 in 8 known pregnancies, the vast majority in the first trimester, and almost never caused by anything the mother did. That statistic is why many people wait for the 12-week scan to announce, and it's also why the fear can shadow these weeks. Two anchors help: report symptoms promptly rather than googling in the dark (early pregnancy units exist precisely for this, and reassurance scans after bleeding are routine), and if the worst does happen, our [miscarriage support guide](/pregnancy/miscarriage-what-to-expect-and-support) covers what to expect and where the real support lives. ## What appointments and admin happen in the first trimester? **Three fixtures: self-refer or GP-refer to midwifery as soon as the test is positive; the booking appointment at 8–10 weeks (history, bloods, screening options, your maternity notes); and the dating scan at 11–14 weeks with optional combined screening. Plus the quiet admin: folic acid and vitamin D daily, medicines reviewed, and free prescriptions via your maternity exemption certificate.** The avoid-list, minus the noise — alcohol (no known safe amount), smoking (help via NHS stop-smoking services doubles quit rates), the short food list (unpasteurised and mould-ripened cheeses, pâté, raw/undercooked meat, liver, swordfish/marlin/shark, capped caffeine at 200mg a day — our [foods-to-avoid answer](/answers/foods-to-avoid-pregnant) has the current full version), cat litter without gloves, and very hot tubs. Everything else in the average anxious first-trimester search history — hair dye after week 12, flying, sex, lifting a toddler, that glass of wine before the test was positive — is fine. ## Which gear is worth getting right? Shortlists we actually research — rankings can't be bought, and every pick links to retailers we've verified. [ Best-of guide ### Best Pregnancy Pillows UK The best pregnancy pillows in the UK — full-body, wedge and multi-use options compared for side-sleeping, back support and feeding afterwards. 5 picks compared ](/best/best-pregnancy-pillows-uk/)[ Best-of guide ### Best Maternity & Nursing Bras UK The best maternity and nursing bras in the UK — wire-free comfort, one-handed clips and sizing guidance for pregnancy and breastfeeding. 5 picks compared ](/best/best-maternity-nursing-bras-uk/)[ Best-of guide ### Best Pregnancy Skincare UK Best pregnancy-safe skincare in the UK — moisturisers, stretch-mark oils and bump care compared, with NHS-aligned ingredients to skip. 6 picks compared ](/best/best-pregnancy-skincare-uk/) ## What questions come up most? When should I see a midwife after a positive test? Contact your GP surgery or self-refer to your local maternity service as soon as the test is positive — most areas accept online self-referral. The first proper appointment (booking) happens at 8–10 weeks, but referring early secures the 11–14 week dating scan slot and gets folic acid and medicines advice flowing immediately. How accurate are due date calculators? They apply the same method midwives use — 280 days from your last period, adjusted for cycle length — so they’re accurate as estimates, but the 11–14 week dating scan supersedes them, and only about 1 in 20 babies actually arrives on the due date. Treat the date as the centre of a five-week normal window. When does morning sickness start and end? Nausea typically begins around weeks 5–6, peaks with the hCG hormone at weeks 8–10, and eases substantially between weeks 12 and 16 — though a minority carry it further. Sickness you can’t keep fluids through is hyperemesis gravidarum: contact your GP or midwife the same day, because effective treatment exists. Can I exercise in the first trimester? Yes — continuing your existing exercise is actively encouraged, with common-sense adjustments: listen to fatigue, stay hydrated and cool, and skip contact sports and anything with falling risk. If you weren’t active before, walking, swimming and pregnancy yoga are the NHS-recommended ways in. ## Sources & further reading * [ Your pregnancy care ](https://www.nhs.uk/pregnancy/your-pregnancy-care/) — NHS * [ Vomiting and morning sickness ](https://www.nhs.uk/pregnancy/related-conditions/common-symptoms/vomiting-and-morning-sickness/) — NHS ## On this page * [ 1 How is my pregnancy dated — and when is my due date? ](#how-is-my-pregnancy-dated-and-when-is-my-due-date) * [ 2 Why do I feel so sick and exhausted? ](#why-do-i-feel-so-sick-and-exhausted) * [ 3 Is bleeding in early pregnancy always bad news? ](#is-bleeding-in-early-pregnancy-always-bad-news) * [ 4 What appointments and admin happen in the first trimester? ](#what-appointments-and-admin-happen-in-the-first-trimester) ## At a glance First trimester Weeks 1–12 (from LMP) Sickness peak Weeks 8–10, easing by 12–16 Key appointments Booking 8–10w · scan 11–14w Daily 400mcg folic acid + vitamin D Any bleeding Same-day advice, always Our promise Health-adjacent points cite NHS or equivalent guidance. This article is general information, not medical advice — see our [editorial policy](/editorial-policy/). ## Keep reading [ Pregnancy ### Early Pregnancy Symptoms: What You Might Notice Before You Test The early pregnancy symptoms some people notice before a missed period, why they overlap heavily with PMS, and why a test is the only reliable way to know. ](/pregnancy/early-pregnancy-symptoms-before-a-test/)[ Pregnancy ### Signs of Labour: What to Expect and When to Call Your Midwife How to recognise the signs that labour has started, the difference between early and established labour, and exactly when the NHS says to call your midwife. ](/pregnancy/signs-of-labour-what-to-expect/)[ Pregnancy ### Pregnancy To-Do List: What to Sort Each Trimester A calm, trimester-by-trimester UK pregnancy checklist — appointments, paperwork, buying decisions and the things everyone forgets until week 39. ](/pregnancy/pregnancy-to-do-list-by-trimester/)