13.4 Puerperal Sepsis & Postnatal Maternal Care
Key Takeaways
- Puerperal pyrexia is defined as a temperature of 38.0°C (100.4°F) or higher occurring on any 2 days during the first 10 days postpartum (excluding the first 24 hours).
- Puerperal sepsis is a genital tract infection occurring between labor/rupture of membranes and 42 days postpartum; endometritis is the most common manifestation.
- Major risk factors include prolonged rupture of membranes (>18-24 hours), multiple digital vaginal examinations, emergency C-section, and retained products of conception (RPOC).
- Management of puerperal sepsis requires broad-spectrum IV triple antibiotic coverage (e.g., Ampicillin + Gentamicin + Metronidazole), evacuation of RPOC, and anticoagulation for septic pelvic thrombophlebitis.
- Uterine involution progresses at ~1 cm/day (non-palpable abdominally by day 10-12); normal lochia evolves from rubra (days 1-4) to serosa (days 5-9) to alba (days 10-14).
Puerperal Sepsis & Postnatal Maternal Care
1. Puerperal Pyrexia & Puerperal Sepsis Definitions
Puerperal Pyrexia
Defined by the British Congress of Obstetrics and Gynaecology as a oral temperature of 38.0°C (100.4°F) or higher maintained or recurring on any 2 separate days within the first 10 days postpartum, excluding the first 24 hours. (Fever in the first 24 hours is usually due to dehydration, minor atelectasis, or surgical stress).
Puerperal Sepsis
Defined by the World Health Organization (WHO) as an infection of the genital tract occurring at any time between the onset of rupture of membranes or labor and the 42nd day postpartum, characterized by fever and one or more of the following:
- Pelvic pain or tenderness
- Abnormal or foul-smelling vaginal discharge (lochia)
- Delay in uterine involution (subinvolution)
2. Etiology and Risk Factors of Puerperal Sepsis
Risk Factors
- Antenatal: Anemia, malnutrition, low socioeconomic status, chronic illness, immunosuppression, unhygienic personal hygiene.
- Intrapartum: Prolonged rupture of membranes (PROM > 18–24 hours), prolonged labor, frequent digital vaginal examinations (>5 examinations), traumatic instrumental delivery (forceps/vacuum), emergency Cesarean section (5 to 10-fold higher risk than elective C-section), internal fetal monitoring.
- Postpartum: Retained products of conception (RPOC - placental fragments or membranes), secondary hemorrhage, unsterile perineal repair, vulvar/vaginal hematoma.
Microbiological Etiology
Puerperal sepsis is predominantly a polymicrobial infection originating from endogenous flora of the lower genital tract or exogenous contamination.
| Pathogen Category | Specific Organisms | Clinical Significance |
|---|---|---|
| Gram-Positive Aerobes | Streptococcus pyogenes (Group A Strep - GAS), Staphylococcus aureus (including MRSA), Enterococcus faecalis | S. pyogenes is highly virulent, causing fulminant toxic shock syndrome with scanty, odorless lochia. |
| Gram-Negative Aerobes | Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis | Common intestinal commensals; frequent cause of urinary tract infection and endometritis. |
| Anaerobes | Bacteroides fragilis, Peptostreptococcus, Clostridium perfringens | Prominent in late, necrotic infections and pelvic abscesses; C. perfringens causes gas gangrene and intravascular hemolysis. |
3. Pathology and Clinical Manifestations
Anatomical Sites of Infection
- Local Perineal/Vaginal Wound Sepsis: Infection of episiotomy or perineal laceration. Presents with localized pain, erythema, edema, purulent wound discharge, and wound dehiscence.
- Puerperal Endometritis (Most Common): Infection of the placental site and decidua. Presents on day 3–5 with spiking fever, chills, lower abdominal pain, marked uterine tenderness, and foul-smelling purulent lochia.
- Parametritis & Pelvic Cellulitis: Spread of infection via lymphatics into the broad ligament. Presents with high fever, lateral pelvic tenderness, and fixed uterine mass.
- Septic Pelvic Thrombophlebitis (SPT): Extension of infection along pelvic veins (ovarian veins). Characterized by persistent high-grade fever with rigors that fails to respond to broad-spectrum antibiotics alone ("puerperal fever of unknown origin"). Diagnosed by contrast CT/MRI showing thrombosis of the ovarian vein.
- Generalized Peritonitis & Septic Shock: Free pus in peritoneal cavity, paralytic ileus, rebound tenderness, hypotension, oliguria, and altered mental status.
4. Diagnostic & Therapeutic Management Protocol
Diagnostic Workup
- Detailed clinical history and physical examination (abdominal palpation for uterine height, tenderness, and involution).
- Sterile speculum examination: assess lochia odor/color and cervical os; take high vaginal and endocervical swabs for Gram stain and aerobic/anaerobic culture.
- Laboratory tests: CBC (marked leukocytosis >20,000/mm³ with neutrophilic left shift), blood cultures (x2 sites during fever spikes), urine culture.
- Pelvic Ultrasonography (USG): Essential to evaluate uterine size, rule out Retained Products of Conception (RPOC), and detect pelvic abscesses or thrombophlebitis.
Empirical Antibiotic Therapy (Triple Therapy)
Start parenteral broad-spectrum antibiotics immediately after taking culture swabs:
- Regimen A (Classic Triple Therapy):
- Ampicillin 2g IV q6h (covers Gram-positive aerobes & Enterococci)
- Gentamicin 5 mg/kg IV once daily (covers Gram-negative enteric bacilli)
- Metronidazole 500 mg IV q8h (covers anaerobes like Bacteroides)
- Regimen B (Gold Standard Post-C-Section):
- Clindamycin 900 mg IV q8h + Gentamicin 5 mg/kg IV once daily (provides ~95% efficacy against polymicrobial pelvic infections).
- Duration: Continue IV therapy until the patient is afebrile and symptom-free for 48 hours, then transition to oral antibiotics to complete a 10–14 day total course.
Surgical & Supportive Measures
- Evacuation of RPOC: If USG confirms retained placental tissue, perform gentle suction curettage/evacuation only after 24–48 hours of effective IV antibiotic coverage to prevent systemic bacteremic dissemination.
- Drainage of Abscess: Pelvic or wound abscesses require prompt surgical drainage or image-guided percutaneous drainage.
- Management of SPT: Add therapeutic anticoagulation with Low Molecular Weight Heparin (LMWH) to broad-spectrum antibiotics; fever usually defervesces within 48–72 hours of starting heparin.
5. Normal Puerperium Physiology & Postnatal Care
Definition & Involution of Uterus
The puerperium is the 6-week period following childbirth during which maternal pelvic organs revert to their non-pregnant anatomical and physiological state.
- Uterine Weight: Decreases from ~1000g immediately post-delivery to ~500g at 1 week, ~300g at 2 weeks, and ~60g (normal size) at 6 weeks.
- Fundal Height: Immediately post-delivery, the fundus is palpable at or just below the umbilicus. It descends at a rate of ~1 cm (one fingerbreadth) per day. By day 10–12, the uterus becomes a pelvic organ and is no longer palpable abdominally.
Lochia Sequence
Lochia is the vaginal discharge during the puerperium, consisting of blood, decidual tissue, leukocytes, and mucus:
- Lochia Rubra (Days 1–4): Red in color; composed mostly of fresh blood, decidual shreds, vernix caseosa, and lanugo hair.
- Lochia Serosa (Days 5–9): Pinkish or brownish; composed of serous exudate, leukocytes, erythrocytes, mucus, and cervical discharge.
- Lochia Alba (Days 10–14+): Yellowish-white; composed primarily of leukocytes, epithelial cells, fat, mucus, and bacteria. Total duration: 2 to 3 weeks.
Lactation Physiology & Postnatal Care
- Prolactin: Secreted by anterior pituitary; stimulates alveolar epithelial cells for milk production/synthesis.
- Oxytocin: Secreted by posterior pituitary; causes contraction of myoepithelial cells surrounding alveoli leading to milk ejection (("let-down" reflex)).
- Breast Care: Prevent nipple damage by ensuring proper latch (areola inside baby's mouth). Treat engorgement with frequent feeding, cold compresses, and breast pumping. Mastitis (S. aureus) presents with focal wedge-shaped breast erythema, tenderness, and fever; treat with dicloxacillin/flucloxacillin and continue breastfeeding.
- 6-Week Postnatal Visit: Assess uterine involution, episiotomy/C-section scar healing, maternal mental health (screen for postpartum depression using Edinburgh scale), offer Pap smear if due, and initiate postpartum contraception (Lactational Amenorrhea Method [LAM], Progestin-Only Pills [POP], DMPA injection, or PPIUCD).
A postpartum woman on Day 4 following an emergency Cesarean section develops a high fever of 39.2°C, lower abdominal pain, marked uterine tenderness, and foul-smelling vaginal discharge. Ultrasonography reveals an empty uterine cavity. Which of the following is the empirical IV antibiotic regimen of choice?
By which postpartum day should the normal involuting uterus become a pelvic organ and no longer be palpable abdominally?
A 26-year-old postpartum patient treated for puerperal endometritis continues to spike high-grade fevers with chills on Day 5 despite 72 hours of appropriate IV triple antibiotic therapy. Repeat pelvic USG shows no retained placental tissue or fluid collections. What is the most likely diagnosis, and what drug should be added to her regimen?
What hormone is primarily responsible for the ejection ('let-down' reflex) of milk from myoepithelial cells surrounding mammary alveoli during lactation?