Rapid review: obstetrics

• This page is a revision shortcut through the classic obstetric presentations. Each block gives the picture in plain clinical words, the single most likely diagnosis, the best first test, the best first treatment, the commonest trap and a pointer to the full MedGrasp topic. ^[5]
• Read it after you know basic antenatal care, the normal stages of labour and the standard postpartum examination, not before: the full topics explain why each answer is right.
• Many apparently "obstetric" diagnosis questions are really pattern-recognition questions, so focus on the discriminating feature in each block rather than memorising the list.
• When a number is given here it comes from the guideline named in that block. Use your local maternity pathway, formulary and the named guideline before acting on any dose.
• A red flag always wins over a favourite diagnosis: bleeding with pain and shock, severe headache or visual disturbance after 20 weeks, a single severe blood-pressure reading, a pathological cardiotocograph, or fever with rigors in a woman who has recently given birth.

By the end of this page you should be able to:

1. Recognise the classic presenting picture of each major obstetric presentation.
2. Choose the most likely diagnosis and the best first test for each.
3. State the best first, evidence-based treatment and the commonest wrong answer that an examination or a rushed clinician makes.
4. Screen and triage antenatal patients using simple, dated checkpoints.
5. Separate pregnant women who need routine care from those who need same-day admission.
6. Use the full MedGrasp topic links for detail, doses and follow-up.

Each section follows the same five lines so that you can scan a whole topic in seconds: the picture as the patient or the examiner describes it, the single most likely diagnosis, the best first test, the best first treatment and the trap. Where a named MedGrasp topic exists, the last line points to it in the form discipline/slug so you can open it directly. Brackets such as (3) are citations to the numbered reference list at the end of the page.

Antenatal care is presented to you in at least three ways: a woman who attends for a routine booking visit, a woman found to have a risk factor for a complication, and a woman who presents with a specific first-trimester or second-trimester problem such as nausea, bleeding or hypertension.

Routine booking. Presenting picture. A woman in early pregnancy presenting to maternity services, often before 10 weeks, for her first appointment. She may not yet have had any investigations.

Most likely diagnosis / state. An early, uncomplicated singleton pregnancy is the norm; the visit exists to establish dates, to identify medical, social and fetal risk, and to set the timetable for the rest of the pregnancy. If a woman contacts or is referred to maternity services later than 9 weeks and 0 days of pregnancy, the appointment should be offered to take place within 2 weeks (1). ^[1]

Best first tests. Confirm pregnancy and viability, estimate gestation, take a full history and examination, and offer the routine screening set: infectious diseases in pregnancy, sickle cell and thalassaemia screening, blood group and antibodies, and the fetal anomaly screening programme (1). Offer an ultrasound scan at 11 weeks and 2 days to 14 weeks and 1 day to date the pregnancy and, if she opts in, to screen for Down syndrome, Edwards syndrome and Patau syndrome, followed by a scan at 18 weeks and 0 days to 20 weeks and 6 days to screen for fetal anomalies (1). Plan 10 routine antenatal appointments with a midwife or doctor for nulliparous women and 7 for parous women, with more if medical, social or emotional needs demand them (1). ^[1]

Best first management. Standard antenatal care with continuity of carer where the service can provide it, a written schedule, contact numbers for urgent concerns such as pain and bleeding, and advice about how to monitor fetal movements. Do not offer routine ultrasound scans after 28 weeks in an uncomplicated singleton pregnancy (1). From 24 weeks onward, measure the symphysis fundal height at each appointment unless the woman is having regular growth scans, plotting it on a growth chart, and offer an ultrasound for fetal growth and wellbeing when the measurement is small for dates (1). At every contact after 24 weeks and 0 days, ask about fetal movements and advise contacting maternity services at any time of day or night if movements are reduced (1). ^[1]

Commonest wrong answer. Treating a low-risk pregnancy as if it needs frequent scanning and intervention, or, conversely, missing an abnormality because you did not act on a small symphysis fundal height measurement or on the woman's own concern about movements.

Full topics: Antenatal care and preconception care (obstetrics/antenatal-care-and-preconception-care); Antepartum fetal surveillance (obstetrics/antepartum-fetal-surveillance).

Prenatal screening. Presenting picture. A woman attending the first-trimester scan or the booking visit, asking what tests are available for chromosomal abnormalities, or a high-risk screen returned after testing.

Most likely diagnosis / context. Most pregnancies are unaffected; screening exists to identify a minority who need a diagnostic test. Every pregnant person should be offered both screening and diagnostic options after an informed discussion and has the right to accept or decline any part (1).

Best first test. Start with screening (ultrasound measurement of the nuchal translucency plus serum markers, and/or cell-free DNA), not with a diagnostic test, in a low-pretest-probability pregnancy. Offer invasive diagnostic testing (chorionic villus sampling from 11 weeks, amniocentesis from 15 weeks) to those who screen positive, who have a personal or family history suggesting a chromosomal disorder, or who choose it, after the woman has been counselled about the small procedure-related loss rate.

Best first management. Document the offer and the woman's decision, provide clear information about screening as an estimate of chance rather than a diagnosis, and refer to a fetal medicine service whenever a result is inconclusive, unexpected or discordant with the ultrasound.

Commonest wrong answer. Calling a screening test "diagnostic", or assuming that a negative screen excludes every abnormality: cell-free DNA is the most sensitive screen for the common trisomies but remains a screen, and an abnormal first-trimester ultrasound appearance always deserves a specialist review regardless of the screen result.

Full topic: Prenatal screening and diagnostic testing (obstetrics/prenatal-screening-and-diagnostic-testing).

Risk factor present at booking, such as high risk of pre-eclampsia. Presenting picture. A woman who, at booking, has hypertension, chronic kidney disease, autoimmune disease or a strong family or personal history of pre-eclampsia, placing her in a high-risk group.

Best first management. Advise a daily low-dose aspirin (75 to 150 mg) from the 12th week of pregnancy and continue it to delivery for women at high risk of pre-eclampsia, or for those with more than one moderate risk factor (3). Assess her blood pressure at each visit using a device validated for use in pregnancy, because early treatment at 135/85 mmHg is the target once she is on medication (3). ^[3]

Commonest wrong answer. Offering aspirin only "to be safe" to every pregnant woman without risk assessment, or starting it after the recommended 12 weeks and expecting the same protection ^[3].

Full topics: Gestational and chronic hypertension in pregnancy (obstetrics/gestational-and-chronic-hypertension-in-pregnancy); Pre-eclampsia, HELLP and eclampsia (obstetrics/preeclampsia-hellp-and-eclampsia).

Bleeding before viability is one of the commonest reasons for attendance in early pregnancy. The three conditions you must sort quickly are a viable intrauterine pregnancy with bleeding, a miscarriage and an ectopic pregnancy.

Ectopic pregnancy. Presenting picture. A woman of reproductive age with a positive pregnancy test, lower abdominal pain (often unilateral), vaginal bleeding that tends to be dark, and shoulder-tip pain or dizziness if she is bleeding internally. Many women have no symptoms until rupture, and a ruptured tube presents as an acute abdomen with shock. Risk factors include tubal damage after infection or surgery, smoking and assisted conception, but most women with an ectopic pregnancy have no identifiable risk factor.

Most likely diagnosis. An ectopic, usually tubal, pregnancy once an intrauterine pregnancy has not been seen on transvaginal ultrasound and the woman is symptomatic. A pregnancy of unknown location needs follow-up rather than a label.

Best first test. Transvaginal ultrasound combined with serial serum beta-human chorionic gonadotrophin, interpreting the hormone trend against the ultrasound findings. An empty uterus with an adnexal mass or free pelvic fluid strongly suggests an ectopic pregnancy; an empty uterus with a rapidly rising hormone level and no symptoms is not yet a diagnosis. Beware single hormone thresholds: setting the discriminatory level high prevents mistaking a very early intrauterine pregnancy for an ectopic.

Best first treatment. A stable small tubal ectopic with a low level of hormone and no fetal cardiac activity can be managed expectantly or with a single intramuscular dose of methotrexate, with close follow-up of hormone levels. An unstable woman, a ruptured ectopic, a large or haemodynamically active mass, or one in which a viable intrauterine pregnancy has not been excluded needs surgery, most often by laparoscopy. Give RhD immunoglobulin to RhD-negative women according to local protocol after surgical management. Whatever route is chosen, the tube and future fertility should be discussed candidly and early.

Commonest wrong answer. Assuming an empty uterus with a positive pregnancy test is "too early to see" and sending the woman home without a plan; or giving methotrexate before an intrauterine pregnancy has been reliably excluded. A negative or falling pregnancy test in a woman previously thought to have an ectopic also needs review, because a "resolving" pattern can hide a persistent trophoblast.

Full topic: Ectopic pregnancy (obstetrics/ectopic-pregnancy).

Miscarriage. Presenting picture. Bleeding with or without pain in early pregnancy. The cervix may be closed with a potentially viable fetus (threatened), open with tissue (incomplete), closed with a non-viable fetus that has not been passed (missed), or the process may be complete. Vaginal bleeding after a known viable pregnancy should still prompt a scan.

Most likely diagnosis. Early pregnancy loss, most single first-trimester losses being caused by random embryonic chromosomal abnormalities, which is why miscarriage is common and usually not anyone's fault. Aneuploidy is responsible for roughly half of early losses.

Best first test. Transvaginal ultrasound, repeated 7 to 14 days later when dates are uncertain and viability cannot yet be determined, rather than a single scan. Accurate scanning prevents treating a pregnancy that is still viable.

Best first treatment. For a confirmed miscarriage, expectant management for 7 to 14 days is a reasonable first option; medical management uses mifepristone followed by misoprostol for a missed miscarriage and misoprostol alone for an incomplete miscarriage; surgical aspiration under local or general anaesthesia is equally valid and should be offered as a choice. Provide analgesia, anti-emetics, and after the first trimester consider the need for anti-D immunoglobulin in RhD-negative women. Psychological support and clear information about what to expect should accompany every option.

Commonest wrong answer. Treating a single scan as diagnostic, so a viable pregnancy is labelled a miscarriage; or choosing medical management without checking for contraindications such as haemodynamic instability, sepsis or significant bleeding, which makes surgical evacuation the safer route.

Full topic: Miscarriage and recurrent pregnancy loss (obstetrics/miscarriage-and-recurrent-pregnancy-loss).

Recurrent pregnancy loss. Presenting picture. A couple who have lost two or more pregnancies, often before 10 weeks, and are anxious and looking for a cause.

Most likely diagnosis. Recurrent loss is usually multifactorial; definitions differ (two or more losses on an ESHRE definition, three or more first-trimester losses on an RCOG definition) and investigating after two losses is reasonable when a pathological cause is suspected.

Best first tests. A phased, sensitive work-up: detailed history and examination, pelvic ultrasound, parental karyotype, antiphospholipid antibodies, screening for thyroid disease and, where suggested by the history, thrombophilia, anatomy and endocrine testing. Keep the search for rare causes proportionate.

Best first management. Reassure the couple that the outlook after recurrent loss is better than is widely believed, treat any specific finding (for example a uterine anomaly or antiphospholipid syndrome), and avoid unproven interventions.

Commonest wrong answer. Ordering an exhaustive, undirected panel of tests in a woman who has had two early losses, or prescribing immunoglobulin, steroids or aspirin without a specific indication.

Full topic: Miscarriage and recurrent pregnancy loss (obstetrics/miscarriage-and-recurrent-pregnancy-loss).

Any bleeding after 24 weeks is antepartum haemorrhage until proven otherwise and needs assessment.

Antepartum haemorrhage overall. Presenting picture. Bleeding after 24 weeks, from a show of blood to a sudden torrent. The woman may be stable or in shock; the fetus may be well or already compromised.

Most likely diagnosis. Depends on the history: painless bleeding suggests placenta praevia; painful bleeding with a hard uterus suggests abruption. Confirm at the bedside with blood pressure, pulse, fundal tenderness, CTG and an ultrasound for placental site before any vaginal examination.

Best first test. An ultrasound for placental site and a cardiotocograph, together with full blood count, group and save (crossmatch if bleeding is heavy) and urinalysis. If the placenta covers or touches the cervical os, a digital or speculum vaginal examination is avoided.

Best first treatment. Resuscitate, gain intravenous access and give crystalloid if shocked, quantify and document blood loss, and deliver the pregnancy when the mother or the fetus is at risk. Stable minor praevia may be managed expectantly with prepared planned caesarean birth; abruption with maternal or fetal compromise needs delivery without further delay.

Commonest wrong answer. Performing a vaginal examination before excluding placenta praevia, or dismissing a small bleed in a woman with a known low-lying placenta as "just a show".

Full topic: Antepartum haemorrhage: placenta praevia and abruption (obstetrics/antepartum-haemorrhage).

Hypertensive disorders are usually discovered at a routine antenatal visit and are classified by gestation, proteinuria and organ involvement.

Chronic and gestational hypertension. Presenting picture. A blood pressure of 140/90 mmHg or higher on two occasions at least four hours apart, either before pregnancy or before 20 weeks (chronic) or arising after 20 weeks without proteinuria or other features (gestational). She may have headache, visual changes or epigastric discomfort when the condition is severe.

Most likely diagnosis. Chronic (including essential) hypertension if present before pregnancy or before 20 weeks; gestational hypertension if it arises later and settles after birth.

Best first test. Automated blood pressure with a cuff validated for pregnancy, repeated on the same or a separate occasion, plus urine dipstick for protein and a baseline maternal blood panel.

Best first treatment. For chronic or gestational hypertension that needs drug treatment, offer labetalol first, nifedipine for women in whom labetalol is unsuitable, and methyldopa if neither is suitable, based on side-effect profiles and the woman's preference, aiming for a target blood pressure of 135/85 mmHg (3). Advise Rh-positive newborn care as needed; after birth, management follows the NICE NG133 postnatal recommendations by diagnosis: in chronic hypertension aim to keep blood pressure below 140/90 mmHg and continue treatment if required, with a GP or specialist review at 2 weeks and a further review at 6 to 8 weeks; in gestational hypertension reduce antihypertensive treatment when blood pressure falls below 130/80 mmHg; in pre-eclampsia, for women who have taken antihypertensive treatment, continue treatment, consider reducing it when blood pressure falls below 140/90 mmHg and reduce it when blood pressure falls below 130/80 mmHg (3). Women with chronic hypertension should also be given low-dose daily aspirin (75 to 150 mg) from the 12th week (3). ^[3]

Commonest wrong answer. Treating a single raised reading in clinic as hypertension, or prescribing a beta blocker other than labetalol and ignoring the fetal circulation, or stopping all treatment immediately because the woman feels well.

Full topic: Gestational and chronic hypertension in pregnancy (obstetrics/gestational-and-chronic-hypertension-in-pregnancy).

Pre-eclampsia, eclampsia and HELLP syndrome. Presenting picture. New hypertension after 20 weeks with proteinuria (24-hour protein 0.3 g or more, or a raised protein-to-creatinine ratio) or evidence of maternal organ dysfunction (thrombocytopenia, rising creatinine or transaminases, neurological or visual symptoms, pulmonary oedema, fetal growth restriction). Headache, visual scotomata, epigastric pain, hyper-reflexia and clonus warn of severe disease. Eclampsia is a tonic-clonic seizure in this context. HELLP syndrome is haemolysis, elevated liver enzymes and low platelets.

Most likely diagnosis. Pre-eclampsia, with worsening to severe features or HELLP in a subgroup that can deteriorate over hours. Always check whether the high blood pressure is chronic rather than new. ^[3]

Best first test. Blood pressure, urine protein by dipstick or protein-to-creatinine ratio, full blood count, platelets, creatinine, urate, alanine transaminase, bilirubin and lactate dehydrogenase; plus a cardiotocograph for the fetus. A platelet count below 150 x 10^9/L, creatinine of 90 micromol/L or higher or an alanine transaminase above 70 IU/L (or twice the upper limit of normal) marks severe disease on NICE guidance, together with sustained systolic pressure of 160 mmHg or higher (3). Do not preload women with intravenous fluids before establishing epidural analgesia, and in severe pre-eclampsia limit maintenance fluids to 80 mL/h (3). ^[3]

Best first treatment. Stabilise, control blood pressure in severe hypertension with labetalol, oral nifedipine or intravenous hydralazine, and start magnesium sulfate with a 4 g intravenous loading dose given across 5 to 15 minutes, then a maintenance infusion at 1 g per hour for 24 hours (or 24 hours after the last fit) if severe features are present, repeating a 2 g to 4 g bolus for a recurrent fit. Magnesium sulfate, not diazepam or phenytoin, is the anticonvulsant (3). Definitive treatment is birth, with timing set by severity, gestation, maternal and fetal condition; antenatal corticosteroids and magnesium for fetal neuroprotection if preterm birth is likely (3). Corticosteroids should not be used to treat HELLP itself (3). ^[3]

Commonest wrong answer. Giving diazepam or phenytoin instead of magnesium sulfate; assuming a normal platelet count rules out pre-eclampsia (it only describes severity); or delaying delivery in severe pre-eclampsia because the woman looks stable on treatment.

Full topics: Gestational and chronic hypertension in pregnancy (obstetrics/gestational-and-chronic-hypertension-in-pregnancy); Pre-eclampsia, HELLP and eclampsia (obstetrics/preeclampsia-hellp-and-eclampsia).

Diabetes first detected in pregnancy carries a heavy burden of macrosomia, birth injury, shoulder dystocia, neonatal hypoglycaemia and later type 2 diabetes.

Presenting picture. A woman with risk factors at booking (BMI 30 kg/m2 or higher, a previous baby weighing 4.5 kg or more, previous gestational diabetes, a first-degree relative with diabetes, or a high-prevalence ethnicity), often with a history of polyuria or recurrent infection and with possible glycosuria. Many women are asymptomatic. ^[2]

Most likely diagnosis. Gestational diabetes mellitus, most likely when risk factors coexist. Pre-existing, undiagnosed type 2 diabetes is a minority and matters for treatment choice.

Best first test. Risk assessment at booking, but not fasting plasma glucose, random glucose, HbA1c, a glucose challenge test or urinalysis alone, which are poor predictors used in that way. Offer a 75 g two-hour oral glucose tolerance test to all women with risk factors at 24 to 28 weeks; for those with previous gestational diabetes, offer testing as soon as possible after booking and again at 24 to 28 weeks if the first is normal (2). Diagnose gestational diabetes if fasting plasma glucose is 5.6 mmol/L or higher, or the 2-hour value is 7.8 mmol/L or higher on NICE criteria (2). Note that the WHO (IADPSG) criteria use a lower fasting threshold (5.1 mmol/L) but a higher 2-hour threshold (8.5 mmol/L) than NICE's (5.6 and 7.8 mmol/L); guidelines differ and local policy decides which to apply, so state which threshold your unit uses. ^[2]

Best first treatment. Diet and exercise with a dietitian review for most women; self-monitor fasting and one-hour post-meal glucose, and if targets are not met within 1 to 2 weeks add metformin, and then insulin. If fasting plasma glucose is 7.0 mmol/L or higher at diagnosis, offer immediate insulin with or without metformin plus diet and exercise (2). If it is between 6.0 and 6.9 mmol/L with complications such as macrosomia or polyhydramnios, consider immediate insulin (2). Advise regular exercise, such as 30 minutes of walking after a meal, and refer all women to a dietitian (2). After the birth, test fasting plasma glucose at 6 to 13 weeks to exclude diabetes, continue lifestyle advice, and offer the NHS Diabetes Prevention Programme if eligible (2). ^[2]

Commonest wrong answer. Using a finger-prick glucose or urinalysis to "screen" and missing women who need the full oral test; or offering oral hypoglycaemic agents other than metformin without considering the teratogenicity; or stopping follow-up after delivery when the risk of type 2 diabetes is highest.

Full topic: Diabetes in pregnancy (obstetrics/diabetes-in-pregnancy).

Labour is normal until it is not. The skill is to distinguish slow but safe progress from arrest, obstruction or fetal compromise.

Slow progress in the first stage. Presenting picture. A woman in established labour, usually nulliparous, with a cervix that is dilating slowly or not at all over hours, with contractions the woman or the midwife thinks are inadequate.

Most likely diagnosis. Inefficient or incoordinate uterine action in an otherwise normal labour, or an occipito-posterior position delaying descent. True cephalopelvic disproportion is rarer than it is invoked, and is a diagnosis of exclusion.

Best first test. Reassess the whole clinical picture: abdominal palpation for position and descent, vaginal examination for dilatation, station and position, the contraction pattern, and a cardiotocograph if indicated. Exclude a full bladder, explain the need for hydration and reassurance, and record progress on a partogram.

Best first treatment. Set up supportive measures (mobility where safe, hydration, analgesia, reassurance), empty the bladder, consider amniotomy if the membranes are intact, and augment with oxytocin if contractions remain inadequate and the fetus is in a good position. Keep the cardiotocograph on whenever an oxytocin infusion is used; if it becomes pathological, stop the infusion immediately and seek urgent obstetric or senior midwifery review (4). ^[4]

Commonest wrong answer. Starting oxytocin because the clock says so, without checking presentation and station, or diagnosing obstructed labour from a single vaginal examination.

Full topics: Normal labour and delivery (obstetrics/normal-labour-and-delivery); Labour stages and failure to progress (obstetrics/labour-stages-and-failure-to-progress).

Fetal distress in labour. Presenting picture. An abnormal fetal heart-rate pattern during labour: sustained tachycardia or bradycardia, reduced variability, late or deep variable decelerations. The mother may feel decreased movements or nothing at all, and the cardiotocograph is the window onto the fetus.

Most likely diagnosis. Intrapartum hypoxia from cord compression, uteroplacental insufficiency or a combination, until assessment proves otherwise. A trace classified as pathological should be treated as hypoxia until excluded, not as a pattern to be admired.

Best first test. Continuous cardiotocograph plus a clinical bedside assessment: maternal blood pressure and pulse, uterine activity, temperature, vaginal examination for dilatation and descent, and fetal scalp blood sampling (capillary pH or lactate) if appropriate to the stage of labour and the clinical picture.

Best first treatment. Stop oxytocin, change maternal position, give a 500 mL intravenous crystalloid challenge if hypotension is present, correct hyperthermia, and expedite delivery by the fastest safe route (instrumental if fully dilated and the head is low, otherwise caesarean). Correct the underlying cause when one is found, for example spinning and releasing the cord.

Commonest wrong answer. Chasing the trace for hours while reassuring the mother that "the baby is just sleeping"; or failing to recognise an acute bradycardia that needs immediate delivery rather than a scalp blood sample.

Full topics: Obstetric exam and fetal heart rate monitoring (obstetrics/obstetric-exam-and-fetal-heart-rate-monitoring); Induction of labour and operative delivery (obstetrics/induction-of-labour-and-operative-delivery).

Shoulder dystocia. Presenting picture. The fetal head delivers and then retracts ("turtle sign"), the shoulders fail to deliver with the next contractions despite gentle axial traction, and there is a sudden risk to the fetus.

Most likely diagnosis. Impaction of the anterior shoulder behind the pubic symphysis; the diagnosis is clinical and must not be delayed while waiting for help that should already have been called.

Best first test. None more than the clinical recognition; if in any doubt, or if delivery is not imminent, shout for the multi-professional team and the 24-hour-day test.

Best first treatment. Call for help, stop excessive traction including McRoberts position with the mother's legs sharply flexed, suprapubic pressure, and then internal manoeuvres, delivery of the posterior arm and, if needed, the Zavanelli manoeuvre and symphysiotomy as last resorts. Record the manoeuvres used and prepare for a difficult neonatal resuscitation.

Commonest wrong answer. Applying more and more traction to the head, turning a shoulder dystocia into a brachial plexus injury or a fracture. Once the turtle sign appears, further axial traction is harmful.

Full topic: Shoulder dystocia (obstetrics/shoulder-dystocia).

Malpresentation in late pregnancy. Presenting picture. At a routine antenatal visit after 36 weeks the presenting part is not the vertex; or in labour the fetus is in breech, transverse lie or a brow position.

Most likely diagnosis. Breech presentation, transverse lie, brow or face, with breech being the commonest non-cephalic presentation at term. Consider underlying causes (placenta praevia, uterine anomaly, fetal anomaly, multiple pregnancy) rather than treating the malpresentation as a single entity.

Best first test. Ultrasound for presentation, placental site and fetal wellbeing, in every case where the presenting part is uncertain.

Best first treatment. Discuss external cephalic version from 36 weeks if appropriate and feasible, with a plan for caesarean birth if the fetus remains breech (or for transverse lie, always a caesarean birth). In labour with a breech, continuous fetal monitoring and a skilled operator; avoid forceful extraction of the after-coming head.

Commonest wrong answer. Forcing vaginal breech delivery in a unit without an experienced operator, or forgetting to exclude placenta praevia before attempting version.

Full topics: Fetal malpresentation (obstetrics/fetal-malpresentation); Multiple gestation (obstetrics/multiple-gestation).

Primary postpartum haemorrhage is bleeding within 24 hours of birth in excess of 500 mL after a vaginal delivery; a previous postpartum haemorrhage of over 1,000 mL or requiring blood transfusion is a strong risk factor for recurrence (4). ^[4]

Primary postpartum haemorrhage due to uterine atony. Presenting picture. A soft, "boggy", poorly contracted uterus after delivery, with bleeding that continues despite an empty bladder. The woman may be hypotensive, tachycardic and pale, and the uterus feels large and soft.

Most likely diagnosis. Uterine atony, the commonest single cause. Trauma, retained placental tissue, coagulopathy and, rarely, uterine inversion remain in the differential.

Best first test. Clinical assessment and quantification of blood loss (weighed swabs, drapes), maternal vital signs, full blood count and coagulation, and examination of the uterus and placenta. Examine the genital tract and perineum for lacerations and the uterine cavity for retained tissue when the uterus is well contracted but bleeding continues.

Best first treatment. Call for help; massage the uterus, empty the bladder, ensure intravenous access, give the uterotonic that matches the prophylaxis already given according to NICE (oxytocin alone, oxytocin plus ergometrine, carboprost or misoprostol 800 micrograms sublingually or rectally, with a maximum of 8 carboprost doses at least 15 minutes apart), give tranexamic acid 1 g by intravenous injection over 10 minutes and repeat if necessary after at least 30 minutes, and resuscitate with crystalloid and blood products (4). If bleeding continues, take the woman to theatre, consider balloon tamponade before surgical options, and deliver the placenta or repair trauma as needed. A member of the team should stay with the woman and her companion throughout. ^[4]

Commonest wrong answer. Giving another ergometrine tablet and waiting, rather than moving to second-line uterotonics and a theatre team; or relying on clinical impression alone to judge the size of the bleed. Non-steroidal anti-inflammatory drugs aggravate bleeding in a woman on the edge of disseminated intravascular coagulation, and should be avoided.

Full topic: Postpartum haemorrhage (obstetrics/postpartum-haemorrhage).

Secondary or late postpartum haemorrhage. Presenting picture. Heavy or prolonged bleeding from about 24 hours after birth, sometimes weeks later, often with a small uterus on examination. Fever and malodour suggest infection; a tender, open cervix with clots or tissue suggests retained products.

Most likely diagnosis. Retained placental tissue with or without endometritis; occasionally a large or infected genital-tract laceration or subinvolution of the placental site.

Best first test. Ultrasound for retained products plus full blood count and infection markers. Culture and sensitivity guide antibiotics if infection is suspected.

Best first treatment. Ergometrine and uterotonics for subinvolution, broad-spectrum antibiotics for suspected infection, and evacuation of retained tissue under cover of antibiotics when bleeding or infection persists. A woman who is shocked follows the primary postpartum haemorrhage protocol regardless of timing.

Commonest wrong answer. Assuming late bleeding is "just lochia" and missing endometritis or retained products.

Full topics: Postpartum haemorrhage (obstetrics/postpartum-haemorrhage); Uterine inversion, rupture and Sheehan syndrome (obstetrics/uterine-inversion-rupture-and-sheehan-syndrome).

Fever in a recently delivered woman is puerperal sepsis until proven otherwise. The commonest single cause of a persistent fever after birth is endometritis, an infection of the uterine lining, which occurs after about 1% to 3% of vaginal births and 5 to 10 times more often after caesarean section (7). ^[7]

Endometritis. Presenting picture. Fever or rigors, lower abdominal pain and tenderness, a sub-involuted, tender uterus, and lochia that is offensive, starting usually between day 2 and day 5 after birth; the fever may be absent in early or severe cases.

Most likely diagnosis. Postpartum endometritis, a polymicrobial ascending infection, most common after caesarean section or prolonged rupture of membranes.

Best first test. Full blood count, C-reactive protein, blood and genital-tract cultures, a lactate for sepsis risk, and an ultrasound for retained products if bleeding or a large uterus suggests them.

Best first treatment. Empirical intravenous broad-spectrum antibiotics, most established as gentamicin plus clindamycin, with ampicillin added for significant caesarean or post-caesarean infection, guided by local protocol and culture results. Screen for sepsis at the same time and, if sepsis is suspected, give a broad-spectrum antimicrobial without delay, within 1 hour, plus fluids and monitoring, in line with the guideline for sepsis in pregnant or recently pregnant people (6). Encourage continuing or resuming breastfeeding unless a specific contraindication exists. ^[6]

Commonest wrong answer. Treating with oral antibiotics suited to uncomplicated urinary infection; or ignoring a woman with low-grade fever and tachycardia because she "looks well" in the first 24 hours. Endometritis after group A streptococcal infection can be explosively severe.

Full topic: Postpartum infection (obstetrics/postpartum-infection).

Wound, urinary, breast and pelvic infections. Presenting picture. A fever after birth with localising signs: a tender, erythematous wound; dysuria or loin pain with a positive urine culture; a red, hard, tender breast with fever in a lactating woman; or fever and pain that persist despite antibiotics, suggesting deep pelvic infection or septic pelvic thrombophlebitis.

Most likely diagnosis. Surgical-site infection, urinary tract infection, mastitis or (rarely) septic pelvic thrombophlebitis, often concurrent sites.

Best first test. Inspect the wound and obtain a swab; send a midstream urine; assess the breast; and, if atypical, image the pelvis with ultrasound or computed tomography. Do not trust a urine dipstick that is positive for blood in a postpartum woman without a culture: catheterisation and epidural anaesthesia raise the baseline rate of bacteriuria.

Best first treatment. Match the antibiotic to the site and local resistance pattern, with source control (drainage, removal of foreign material such as sutures, abscess drainage). For mastitis, empty the breast, support continued feeding and use anti-staphylococcal therapy. Septic pelvic thrombophlebitis is treated with broad-spectrum antibiotics; anticoagulation is considered in selected cases by the specialist team.

Commonest wrong answer. Blaming an epidural site or "milk fever" for a high fever and prescribing antipyretics rather than antibiotics; or stopping breastfeeding, which worsens mastitis and milk stasis and is rarely necessary if a suitable antibiotic is used.

Full topics: Postpartum infection (obstetrics/postpartum-infection); Infections in pregnancy (obstetrics/infections-in-pregnancy); Lactation, breastfeeding and mastitis (obstetrics/lactation-breastfeeding-and-mastitis).

Maternal sepsis. Presenting picture. A woman who is pregnant or who has given birth within six weeks, with any combination of fever or hypothermia, tachycardia, tachypnoea, hypotension, rigors, confusion or an ill appearance. Sepsis in this window is an obstetric emergency and a leading global cause of maternal death.

Most likely diagnosis. A septic focus (endometritis, kidney, wound, breast, pneumonia or chorioamnionitis extending postpartum), sometimes with no obvious source on initial assessment.

Best first test. Immediate blood tests (full blood count, C-reactive protein, lactate, renal and liver function, clotting), blood cultures before antibiotics if this does not delay them, and a search for the source with urine, wound and genital-tract cultures and, as needed, chest, renal and pelvic imaging.

Best first treatment. Call the multi-professional team early; give a broad-spectrum antimicrobial without delay, within 1 hour of identifying high-risk criteria, followed by an intravenous fluid bolus; escalate care, remove infected tissue or foreign material, and treat heavy bleeding or disseminated intravascular coagulation with the postpartum haemorrhage protocol (6).

Commonest wrong answer. Waiting for culture results before starting antibiotics in a high-risk recently pregnant woman; or treating sepsis as an ordinary postpartum fever and missing the speed of deterioration.

Full topics: Postpartum infection (obstetrics/postpartum-infection); Maternal mortality and severe morbidity (obstetrics/maternal-mortality-and-severe-morbidity).

Fetal growth problems present either with reduced fetal movements, a small symphysis fundal height at a routine visit, or as an unexpected finding in a high-risk pregnancy.

Fetal growth restriction. Presenting picture. A symphysis fundal height measuring smaller than expected for gestation; a previous small baby; a maternal illness such as hypertension or autoimmune disease; or, in labour, a small infant with meconium-stained liquor. Many women have no symptoms at all and the condition is found at a routine visit.

Most likely diagnosis. A constitutionally small but healthy fetus is common; fetal growth restriction is defined by fetal size and trajectory, with or without abnormal Doppler or other markers, and is a marker of placental insufficiency rather than of a constitutionally small baby. The distinction matters because management and prognosis differ.

Best first test. Plot the fundal height on a growth chart; if it is small for gestational age, offer an ultrasound for fetal growth and wellbeing with measurements of estimated fetal weight, amniotic fluid and umbilical artery Doppler (1). Reduced fetal movements at or after 24 weeks should be assessed with a cardiotocograph and, when indicated, ultrasound (1).

Best first treatment. Monitoring by serial ultrasound and Doppler with a plan agreed with fetal medicine, including timing of delivery, and treating the maternal condition. Antenatal corticosteroids should be given when preterm delivery is likely within seven days. Neonatal resuscitation should be anticipated and, after birth, a full assessment for congenital anomaly, infection and ischaemic injury should be considered in a markedly small infant.

Commonest wrong answer. Labeling every infant below the tenth centile as growth restricted, or reassuring a woman with a small fundal height and recent reduced movements without offering imaging and senior review.

Best first management of a normal trajectory. If the symphysis fundal height is appropriate, there is no additional routine scanning after 28 weeks in an uncomplicated pregnancy, and the woman should be taught the normal pattern of movements and how and when to seek assessment rather than counting kicks in a rigid numerical way (1).

Full topics: Fetal growth restriction and macrosomia (obstetrics/fetal-growth-restriction-and-macrosomia); Antepartum fetal surveillance (obstetrics/antepartum-fetal-surveillance).

Macrosomia and reduced fetal movements. Presenting picture. A large fundal height, a woman noting large-for-dates, a history of gestational diabetes or previous macrosomia, or a previously active fetus with fewer movements.

Most likely diagnosis. A macrosomic fetus, with gestational diabetes as the commonest actionable cause. Reduced fetal movements, if persistent after a normal cardiotocograph and ultrasound, are a marker of a higher risk of stillbirth and need personalised follow-up rather than casual reassurance.

Best first test. Ultrasound for estimated fetal weight, amniotic fluid and for diabetic mothers a recheck of glycaemic control; a cardiotocograph and ultrasound if movements are reduced.

Best first treatment. Deliver according to the diabetic or macrosomic fetal policy once term is reached; if reduced movements continue after a normal trace, escalate with a consultant plan, induction of labour and intrapartum monitoring, rather than repeating a reassuring scan indefinitely.

Commonest wrong answer. Inducing labour early for a single high ultrasound-estimated weight without a clinical reason, or sending a woman home after one normal cardiotocograph despite persistently reduced movements.

Full topics: Fetal growth restriction and macrosomia (obstetrics/fetal-growth-restriction-and-macrosomia); Antepartum fetal surveillance (obstetrics/antepartum-fetal-surveillance).

Antepartum surveillance. Presenting picture. A woman with an ongoing high-risk pregnancy, needing monitoring through the third trimester, with no acute symptom but a list of risk factors on the chart.

Most likely diagnosis. A high-risk pregnancy needing a structured plan, not an admission. The risk assessment started at booking and is revised at every contact.

Best first tests and management. Follow a written third-trimester plan (serial fundal height and conditional scans, blood pressure and proteinuria checks, fetal movement advice, and Doppler surveillance in growth restriction (1)), document each visit, and admit or induce only when a trigger is crossed (blood pressure thresholds, abnormal CTG, abnormal Doppler or a maternal indication).

Commonest wrong answer. Performing tests as a routine without acting on the result, or admitting a woman "just in case" and delivering her preterm without a clear indication.

Full topics: Antepartum fetal surveillance (obstetrics/antepartum-fetal-surveillance); Antenatal care and preconception care (obstetrics/antenatal-care-and-preconception-care).

• Book early: later than 9 weeks and 0 days means an appointment within 2 weeks, with 10 routine contacts for nulliparous women and 7 for parous women.
• A high-risk woman for pre-eclampsia is advised daily aspirin at 75 to 150 mg starting at 12 weeks (3); chronic and gestational hypertension is treated to 135/85 mmHg with labetalol first (3).
• In pre-eclampsia, magnesium sulfate is the anticonvulsant: a 4 g intravenous load given across 5 to 15 minutes, then a maintenance rate of 1 g hourly for 24 hours (3), and corticosteroids do not treat HELLP (3). ^[3]
• Gestational diabetes is risk-factor screened with a 75 g oral glucose tolerance test at 24 to 28 weeks; manage with diet and exercise, metformin, then insulin, and postnatal testing at 6 to 13 weeks (2).
• An ectopic pregnancy must be excluded before any medical miscarriage management, and a single scan is never enough to diagnose it.
• Miscarriage management is expectant, medical or surgical by choice, with anti-D and supportive care.
• Do not perform a vaginal examination before excluding placenta praevia: painless bleeding suggests praevia, painful bleeding suggests abruption.
• A soft "boggy" uterus after birth is uterine atony until proven otherwise: give the matching uterotonic plus tranexamic acid 1 g intravenously (4).
• Suspected sepsis in a recently pregnant woman needs a broad-spectrum antimicrobial within 1 hour (6); endometritis is the commonest cause of a persistent postpartum fever and is initially treated with gentamicin plus clindamycin (7).
• Fetal movements must be asked about after 24 weeks and women should be advised to report reduced movements (1); offer an ultrasound for a small symphysis fundal height (1).
• Do not scan an uncomplicated singleton after 28 weeks (1); do not rely on a single reassuring cardiotocograph to exclude a stillbirth risk.
• Call for help and stop excessive traction at the first "turtle sign": shoulder dystocia is an obstetric emergency.

Plain-text references to MedGrasp topics: Antenatal care and preconception care (obstetrics/antenatal-care-and-preconception-care); Prenatal screening and diagnostic testing (obstetrics/prenatal-screening-and-diagnostic-testing); Antepartum fetal surveillance (obstetrics/antepartum-fetal-surveillance); Ectopic pregnancy (obstetrics/ectopic-pregnancy); Miscarriage and recurrent pregnancy loss (obstetrics/miscarriage-and-recurrent-pregnancy-loss); Antepartum haemorrhage (obstetrics/antepartum-haemorrhage); Gestational and chronic hypertension in pregnancy (obstetrics/gestational-and-chronic-hypertension-in-pregnancy); Pre-eclampsia, HELLP and eclampsia (obstetrics/preeclampsia-hellp-and-eclampsia); Diabetes in pregnancy (obstetrics/diabetes-in-pregnancy); Normal labour and delivery (obstetrics/normal-labour-and-delivery); Labour stages and failure to progress (obstetrics/labour-stages-and-failure-to-progress); Obstetric exam and fetal heart rate monitoring (obstetrics/obstetric-exam-and-fetal-heart-rate-monitoring); Induction of labour and operative delivery (obstetrics/induction-of-labour-and-operative-delivery); Shoulder dystocia (obstetrics/shoulder-dystocia); Fetal malpresentation (obstetrics/fetal-malpresentation); Multiple gestation (obstetrics/multiple-gestation); Postpartum haemorrhage (obstetrics/postpartum-haemorrhage); Uterine inversion, rupture and Sheehan syndrome (obstetrics/uterine-inversion-rupture-and-sheehan-syndrome); Postpartum infection (obstetrics/postpartum-infection); Infections in pregnancy (obstetrics/infections-in-pregnancy); Lactation, breastfeeding and mastitis (obstetrics/lactation-breastfeeding-and-mastitis); Fetal growth restriction and macrosomia (obstetrics/fetal-growth-restriction-and-macrosomia); Maternal mortality and severe morbidity (obstetrics/maternal-mortality-and-severe-morbidity).