Puerperal sepsis from Group A Streptococcus (Streptococcus pyogenes) is the most rapidly fatal cause of postnatal sepsis — GAS produces streptolysin, hyaluronidase, and cytotoxins that cause explosive fascial plane spread. The clinical presentation can be deceptively mild in the first 12-24 hours (low-grade temperature, malaise, 'not quite right') before rapid deterioration to septic shock within hours. Historically, GAS transmission occurred from asymptomatic pharyngeal carriage in healthcare workers, family members, or the patient herself. GPs seeing a postnatally unwell woman must have a very low threshold for same-day hospital assessment — the NEWS2 score should be applied, and any NEWS2 of 5 or above requires an emergency response. GAS sepsis mortality is approximately 20-30% even with optimal treatment — the 'kill the bacteria' and 'support the patient' strategies must both be initiated within 1 hour of diagnosis (Sepsis Six bundle: blood cultures, IV antibiotics, IV fluids, lactate measurement, oxygen, urine output monitoring).

Postpartum psychosis (PP) is a genuine psychiatric emergency that requires same-day specialist assessment and usually hospital admission — it affects approximately 1-2 women per 1,000 deliveries (approximately 1,200 women per year in the UK) and has a bimodal onset: the first peak within 48-72 hours of delivery (rapid onset, often dramatic), and the second peak at 2-4 weeks. The clinical features: rapidly changing mood (euphoria to terror to confusion), grandiose delusions (believing the baby is special or divine, or conversely that the baby is possessed), command hallucinations, disorganised thinking, and severe agitation. The critical safety concern: command hallucinations instructing infanticide or suicide — these are genuine risks in PP, and the GP must assess immediately the safety of both the mother and the baby. A woman with PP who refuses admission needs an urgent MHA (Mental Health Act) assessment if she lacks capacity or poses a risk to herself or her infant. The best outcome: admission to a specialist Mother and Baby Unit (MBU) where the mother-infant bond is maintained during treatment with mood stabilisers and antipsychotics.

The EPDS Question 10 (asking about self-harm thoughts) requires immediate face-to-face clinical assessment regardless of the total score — a score of 1, 2, or 3 on Q10 ('The thought of harming myself has occurred to me... sometimes / quite often / yes, quite often') indicates active suicidal ideation, even if the rest of the EPDS is low. Postnatal suicidality is a distinct clinical picture from general adult suicidality — the methods used in postnatal suicide are often violent (jumping, hanging, drowning) rather than overdose, possibly because the mother is motivated to avoid a failed attempt that might leave her incapacitated and separated from her infant. The MBRRACE-UK Confidential Enquiry into Maternal Deaths consistently identifies that GP failure to act on postnatal suicidality is a preventable factor in maternal death by suicide. Any GP administering EPDS must have a protocol for Q10 positive responses: immediate face-to-face contact, safety assessment, referral to crisis team or perinatal mental health, and documentation.

Postpartum thyroiditis is one of the most commonly missed diagnoses in the postnatal period — it presents in approximately 5-7% of postnatal women (higher in women with pre-existing anti-TPO antibodies or type 1 diabetes) and both phases can be clinically indistinguishable from postnatal depression, anxiety, or general postnatal fatigue. The hyperthyroid phase (1-4 months): palpitations, anxiety, irritability, weight loss, heat intolerance — often attributed to postnatal anxiety or PND and treated with SSRI or CBT without checking thyroid function. The hypothyroid phase (4-8 months): fatigue, low mood, weight gain, cold intolerance — often attributed to PND at this later stage. The key principle: thyroid function tests (TSH + free T4) should be checked in every postnatally unwell woman with symptoms that could be attributed to thyroid dysfunction, especially if: previous PPT, type 1 diabetes, or autoimmune condition. A missed hypothyroid phase of PPT treated as PND with an SSRI (without levothyroxine) will not improve and may cause unnecessary antidepressant prescribing.

The SSRI choice in postnatal depression for breastfeeding mothers requires specific clinical knowledge — not all SSRIs have equivalent safety profiles for breastfeeding infants. Sertraline has the most favourable breastfeeding safety data: it is highly protein-bound, has low milk transfer (approximately 0.5-3% of maternal dose reaches infant), and infant plasma levels are typically undetectable. Multiple studies and systematic reviews consistently show sertraline as the safest SSRI for breastfeeding. Paroxetine and fluvoxamine also have low milk transfer. Fluoxetine has the highest milk transfer of all SSRIs due to its long half-life (and active metabolite norfluoxetine), and should be avoided as a first-choice in breastfeeding if alternatives are available. The LactMed database (NIH) and the UKDILAS (UK Drugs in Lactation Advisory Service) provide up-to-date safety information on individual drugs in breastfeeding. GPs should always check LactMed before prescribing any new medication to a breastfeeding mother.

Trauma-focused CBT and EMDR for birth-related PTSD represent a clinically distinct treatment pathway from standard PND management — traumatic childbirth (emergency Caesarean section, assisted delivery, unexpected complications, perceived loss of control, extreme pain, or infant safety scares) can cause genuine PTSD in approximately 3-4% of postnatal women, with a larger proportion experiencing PTSD symptoms. The diagnostic distinction matters: PTSD from traumatic birth has the same core features as PTSD from any other trauma (flashbacks/intrusive memories of the delivery, avoidance of reminders, hypervigilance), but standard IAPT low-intensity CBT does not address the traumatic memory adequately. Trauma-focused CBT (NICE recommended for PTSD — NG116) involves structured processing of the traumatic event, which is distinct from the behavioural activation and cognitive restructuring used for depression. GPs referring postnatally unwell women with prominent re-experiencing of delivery events should specify 'birth trauma/PTSD' in the referral to ensure the appropriate IAPT pathway (high-intensity, trauma-focused) is selected.

Nipple Raynaud's phenomenon (nipple vasospasm) is a significantly underdiagnosed cause of breastfeeding-associated nipple pain — it affects approximately 20% of breastfeeding women with nipple pain and is caused by vasospasm of the nipple blood vessels triggered by cold air, cold water, or the thermal change after a feed. The characteristic colour change (white blanching, then blue/purple discolouration, then red flushing as blood returns) is pathognomonic. The pain is described as burning, throbbing, or shooting — often occurring after the baby comes off the breast and lasting 1-30 minutes. It is frequently misdiagnosed as Candida nipple infection (thrush) and treated with topical antifungals (which are ineffective). The effective treatment: nifedipine MR 30 mg OD (off-label use — strong case series and clinical consensus data) achieves significant symptom relief in the majority of cases within 1-2 weeks. Thermal precautions (warm compress immediately after feeds, warm clothing, avoiding cold drafts) and avoidance of caffeine and nicotine (vasoconstrictors) are supportive measures.

The domestic violence routine enquiry in postnatal contacts is a NICE NG76 quality standard and a critical safety intervention — UK data consistently shows that domestic violence (DV) starts or escalates during pregnancy and the postnatal period in approximately 30% of cases. The perpetrator may be more controlling during this period as the woman becomes more dependent and isolated. GPs and health visitors conducting postnatal contacts should use the HITS (Hurts, Insults, Threatens, Screams) brief screening tool or a direct compassionate enquiry: 'We ask all new mothers about this — does your partner ever hurt you physically, make you feel afraid, or stop you from doing things you want to do?' The enquiry must be conducted with the partner absent from the room. Any disclosure should be met with: non-judgmental response, safety planning, referral to the local Independent Domestic Violence Advocate (IDVA), and MARAC referral if high risk (DASH risk assessment score ≥14 = high risk).

The 6-week postnatal check is a NICE-recommended quality standard that is frequently shortened or inadequately performed in busy GP practices — it should be a structured appointment of at least 20 minutes covering both maternal and infant health. In England, the 2020 NHS Long Term Plan committed to strengthening the 6-week check, and NHS England published guidance in 2020 specifying the minimum components. The GP-specific components include: BP measurement, EPDS (or referral to health visitor for EPDS), discussion of contraception, perineal assessment if relevant, and baby examination. The baby examination at 6 weeks is a GP responsibility (NIPE — Newborn and Infant Physical Examination) and includes: weight, red reflex (fundoscopy with ophthalmoscope — absent red reflex = urgent paediatric ophthalmology), congenital hip examination (Barlow — dislocatability test; Ortolani — reduction test), heart auscultation, genitalia (undescended testis in boys), and sacral dimple examination. GPs who do not perform the baby examination at the 6-week check are failing to complete the NIPE screening programme.