Ectopic pregnancy remains the leading cause of maternal mortality in the first trimester of pregnancy — responsible for approximately 10–12 maternal deaths per year in the UK despite advances in diagnosis and treatment. The key failure mode in primary care is not thinking of ectopic pregnancy as a differential in a woman of reproductive age with abdominal pain and vaginal bleeding, particularly when the patient has not mentioned or does not know she is pregnant (up to 30% of women with ectopic pregnancy do not know they are pregnant at presentation). The absolute clinical rule is: any woman of reproductive age with abdominal pain or vaginal bleeding must have a pregnancy test performed. A urine pregnancy test costs £0.50 and takes 3 minutes — the failure to perform it is the most common identifiable factor in delayed ectopic diagnosis. The 'no confirmed intrauterine pregnancy' principle is critical — it is not sufficient to know the pregnancy test is positive; what matters is whether an intrauterine pregnancy has been confirmed by ultrasound. A positive pregnancy test + pelvic pain + any bleeding without confirmed IUP on USS = treat as ectopic until proved otherwise. The vaginal examination contraindication in suspected placenta praevia is a fundamental obstetric safety rule — digital vaginal examination can disrupt the placenta overlying the cervical os and trigger catastrophic, immediately life-threatening haemorrhage. This rule applies even in primary care settings where vaginal examination might seem routine: if there is any possibility of placenta praevia (third trimester bleeding, known low-lying placenta from previous scan), no vaginal or speculum examination should be performed before USS confirmation of placental position.

The trimester-based differential is the most practical organising framework for vaginal bleeding in pregnancy because it immediately narrows the differential and determines urgency. The key principle is: any bleeding in the third trimester is a potential obstetric emergency until proved otherwise, and any bleeding in the first trimester without confirmed IUP is a potential ectopic until proved otherwise. Second-trimester bleeding occupies an intermediate position — while often not immediately life-threatening, it includes diagnoses (late miscarriage from cervical incompetence, placenta praevia becoming symptomatic) that carry major implications for the current and future pregnancies. Vasa praevia deserves specific mention because it is rare but carries extremely high fetal mortality when undiagnosed — the rate of fetal death from vasa praevia rupture is approximately 50–75% without prior diagnosis vs less than 3% with antenatal diagnosis and planned Caesarean delivery. Risk factors for vasa praevia include: IVF conception, low-lying placenta, bilobed placenta, succenturiate lobe. NICE guidance and RCOG Green-top guideline on Vasa Praevia recommend that women with risk factors should be offered transvaginal colour Doppler screening at the 20-week anomaly scan. GPs seeing women with these risk factors should ensure the anomaly scan request specifically mentions vasa praevia screening.

The serial serum beta-hCG measurement at 48-hour intervals is the most important diagnostic tool for distinguishing a viable intrauterine pregnancy from a failing pregnancy or ectopic in early pregnancy when the USS cannot yet visualise the IUP — in a healthy intrauterine pregnancy, serum beta-hCG doubles (increases by at least 66%) every 48 hours. An increase of less than 66% over 48 hours indicates a failing pregnancy (miscarriage) or ectopic. A falling beta-hCG over 48 hours confirms a failing or completing miscarriage. A plateau or slowly rising beta-hCG in the absence of a visible IUP on USS is one of the most concerning patterns, as it can indicate a growing ectopic pregnancy and requires urgent EPAU management. The 'discriminatory zone' concept (the beta-hCG level above which an IUP should be visible on transvaginal USS — approximately 1,500–2,000 IU/L) is used in specialist practice to determine when the absence of a visible IUP is diagnostically significant. GPs should understand this concept: if a woman has a beta-hCG above 2,000 IU/L and no visible IUP on transvaginal USS, ectopic pregnancy is strongly suspected and urgent EPAU management is needed. The shoulder tip pain manoeuvre (asking the patient to lie flat for 5 minutes and then asking if they develop right shoulder tip pain) is a useful clinical test for free blood in the peritoneal cavity — blood tracking under the right diaphragm causes referred pain to the right shoulder tip via the phrenic nerve (C3–C5 dermatome). The test has modest sensitivity but is highly specific and takes 5 minutes — a positive result in a woman with a positive pregnancy test and abdominal pain = emergency 999 call.

Vaginal progesterone for threatened miscarriage is one of the most important recent evidence-based developments in early pregnancy care for GPs — the PROMISE trial (2015, NEJM, n=836) and PRISM trial (2019, NEJM, n=4,153) together provide robust evidence that vaginal progesterone 400 mg BD reduces miscarriage rates in women who present with first-trimester bleeding and have a confirmed viable intrauterine pregnancy on USS, with the greatest benefit in women who have had one or more previous miscarriages. NICE NG126 (updated 2021) now recommends offering vaginal progesterone to women with bleeding in the first 12 weeks of pregnancy who have previously had a miscarriage, starting as soon as bleeding is confirmed and continuing to 16 weeks if no further complications. The NNT is approximately 8 (one additional live birth for every 8 women treated). This is a GP-initiatable treatment — the GP does not need to wait for the EPAU to prescribe. The prescription: Cyclogest 400 mg pessaries, insert vaginally BD, from first bleed to 16 weeks gestation. The complete vs incomplete miscarriage USS criteria are important to know because they determine whether a patient needs EPAU intervention or can be managed in primary care: an endometrial thickness of 15 mm or less on USS with a closed cervical os and no visible products = complete miscarriage = primary care management appropriate. An endometrial thickness above 15 mm, visible heterogeneous material, or open os = incomplete miscarriage = EPAU referral for management decision.

Anti-D immunoglobulin administration in Rh-negative women with pregnancy-associated bleeding is one of the most important preventive interventions in obstetric primary care — failure to administer anti-D when indicated is one of the most common sources of maternal harm from GP prescribing errors in obstetrics. The mechanism: if a Rh-negative mother is sensitised to fetal Rh-positive red blood cells (which can enter maternal circulation during any pregnancy-related bleeding event), she develops anti-D antibodies that in subsequent pregnancies can cross the placenta and destroy fetal red blood cells, causing haemolytic disease of the newborn (HDN) — ranging from mild jaundice to hydrops fetalis and intrauterine death. Anti-D immunoglobulin given within 72 hours of the sensitising event prevents maternal sensitisation by destroying fetal red cells before the immune response develops. The NICE NG126 guidance on threatened miscarriage has been updated: before 12 weeks, anti-D is only indicated for threatened miscarriage if the bleeding is heavy or associated with significant pain (light spotting without pain before 12 weeks does not require anti-D). After 12 weeks, any bleeding event requires anti-D. Every GP practice should have a clear protocol for anti-D administration in early pregnancy bleeding — including the blood group result, dose (250 IU before 20 weeks), route (IM deltoid), timing (within 72 hours), and documentation. Recurrent miscarriage (three or more consecutive losses) investigation should include antiphospholipid syndrome testing because this is the only treatable cause with a proven intervention — LMWH + low-dose aspirin in women with antiphospholipid syndrome reduces miscarriage rate from approximately 90% to approximately 30% (NNT approximately 4 for a live birth), one of the most dramatic treatment effects in reproductive medicine.

The GTD surveillance programme in the UK (managed by three specialist centres — Charing Cross Hospital, Weston Park Hospital Sheffield, and Ninewells Hospital Dundee) is one of the most successful examples of centralised cancer surveillance in the world, achieving cure rates of over 98% for all forms of gestational trophoblastic disease including choriocarcinoma. The mechanism is that beta-hCG is a uniquely sensitive and specific tumour marker for GTD — any detectable beta-hCG after evacuation of a molar pregnancy indicates persistent trophoblastic disease requiring chemotherapy. The surveillance programme monitors serial urine beta-hCG samples sent by post to the specialist centre, with treatment initiated promptly if levels plateau or rise. GPs play an important role: ensuring the patient is registered with the GTD centre after molar evacuation, prescribing the oral contraceptive pill (the combined OCP is used to prevent pregnancy-related beta-hCG confusion during surveillance), and NOT prescribing pregnancy until the surveillance programme is completed. The methotrexate treatment protocol for ectopic pregnancy requires specific follow-up that GPs may be involved in — the key post-injection monitoring parameters are: beta-hCG on day 4 and day 7 after injection (the hCG typically rises from day 1–4 before falling — so a rising hCG on day 4 is expected and should not trigger rescue surgery), and a fall of at least 15% from day 4 to day 7 indicates treatment success. Patients must be advised to return immediately if they develop worsening pain (indicating tubal rupture even during apparently successful treatment) and to avoid NSAIDs (which reduce methotrexate renal clearance and increase toxicity).

The language used when a patient has had a miscarriage is one of the most important clinical communication skills a GP can develop — miscarriage is one of the most common and most emotionally devastating experiences that women and their partners can face, yet it is frequently trivialised or minimised by healthcare professionals. The most harmful phrases ('at least it was early,' 'you can try again,' 'it wasn't a real baby yet,' 'nature's way of dealing with abnormalities') are not medically inaccurate but are emotionally dismissive and can cause lasting psychological harm, including prolonged grief, complicated bereavement, and loss of trust in the healthcare system. The Miscarriage Association has published guidance on supportive communication that all GPs should be familiar with. The core elements are: acknowledge the loss directly and specifically, use the word 'baby' if the patient does (follow their language), allow and validate the emotional response, and avoid rushing to 'silver lining' or future-focused statements before the grief has been acknowledged. Many patients describe the GP's few words in the immediate aftermath of miscarriage as either the most healing or most harmful aspect of their entire experience. The recurrent miscarriage investigation after three losses (rather than two) is based on the statistical probability that three consecutive miscarriages is unlikely to be due to chance alone (probability approximately 0.7%), making systematic investigation justified. However, RCOG guidelines note that investigation can reasonably be offered after two consecutive miscarriages in women over 35, because the probability of another loss is high enough to warrant investigation earlier in this group.

The Valproate Pregnancy Prevention Programme (PPP) is a mandatory NHS programme that requires all women of childbearing potential prescribed sodium valproate to be on a formalised risk acknowledgement programme — this includes annual specialist review, contraception counselling, mandatory annual review by a specialist, and a signed acknowledgement of the teratogenicity risks. Valproate is associated with a 10% risk of neural tube defects and a 30–40% risk of developmental delay in exposed children. GPs who encounter a woman who is pregnant or planning pregnancy and taking valproate must immediately contact the prescribing specialist (psychiatry or neurology), as valproate is contraindicated in pregnancy unless there is absolutely no suitable alternative. If the patient is already pregnant on valproate, urgent referral to teratology services and the prescribing specialist is needed. Other teratogenic drugs that require pre-conception review: statins (all contraindicated), ACE inhibitors and ARBs (contraindicated in second/third trimester, caution in first), retinoids (isotretinoin — the RCOG 30-day rule: negative pregnancy test, then start isotretinoin), warfarin (crosses placenta — switch to LMWH ideally before conception), mycophenolate (highly teratogenic — change to azathioprine if immunosuppression needed), thalidomide (absolute contraindication — strict pregnancy prevention programme), methotrexate (teratogenic — stop 3 months before conception). Every GP should perform a medication review for teratogenic drugs when a patient of childbearing age presents, particularly after a pregnancy event.

The safety-net for ectopic pregnancy under surveillance is arguably the most critical safety message in all of early pregnancy care — women managed expectantly (falling beta-hCG) or with methotrexate can rupture their ectopic at any point during the surveillance period, even when the beta-hCG is falling. The tubal rupture can occur without warning in a woman who appeared to be responding to conservative management. Every woman managed conservatively for ectopic must have a clear written safety-net: 'If you develop any significant pelvic pain at any time, call 999 or go to A&E immediately — do not wait to see your GP or phone the EPAU.' This instruction should be documented in the clinical record at every contact during ectopic surveillance. The GTD surveillance centre contact detail (Charing Cross Hospital GTD Centre: 020 3313 5894) is worth having in the practice system — if a GP has a patient who has had a molar pregnancy and loses contact with the surveillance programme, or if a patient presents with vaginal bleeding with a history of previous molar pregnancy, the centre can be contacted directly for advice.