Retained Placental Fragments

Retained placental fragments are pieces of placenta or membranes that stay in the uterus after the placenta is delivered, found in about 1 to 3 percent of births. They prevent proper uterine contraction and cause early bleeding, or late bleeding and infection. They result from accessory lobes, adherent placenta, forceful cord traction, preterm birth and previous uterine surgery.

• Risk factors: succenturiate lobe, previous retained placenta, previous curettage, preterm birth, mismanaged third stage, accreta spectrum.
• Often missed if the placenta is not inspected carefully.
• Easily treated if found early.

Women have persistent bleeding after birth, or late bleeding at 1 to 3 weeks with clots, foul lochia, lower abdominal pain, fever and a bulky tender uterus. The cervical os may be open.

• Uterus larger than expected for days after birth.
• Missing cotyledon or ragged membranes noted at delivery.
• Differential diagnosis: uterine atony, subinvolution of the placental site, endometritis, cervical tear, trophoblastic disease, scar dehiscence, return of menstruation.
• Complications: postpartum haemorrhage, endometritis, sepsis, intrauterine adhesions, placental polyp, anaemia, hysterectomy.

The approach is inspection of the placenta, ultrasound and tests for infection.

• Inspect placenta and membranes after delivery for completeness; check the edge for torn vessels.
• Transvaginal ultrasound: echogenic mass in the cavity, endometrial thickness above 15 mm, colour flow; remember that a thin heterogeneous endometrium early after birth can be normal.
• Haemoglobin, white cell count, C-reactive protein, urine or serum hCG, group and cross-match for heavy bleeding.
• Histology of removed tissue.

The principle is medical management for stable women with small fragments and evacuation for heavy bleeding, infection or large fragments.

• Supportive: observation of lochia, temperature and pulse; admit if bleeding is heavy; two cannulae; transfuse for haemoglobin below 7 g/dL or shock; uterine massage; empty the bladder.
• Pharmacological: oxytocin 10 IU IM then infusion of 40 IU in 1 litre Ringer's lactate at 250 mL per hour; misoprostol 600 micrograms oral or 400 micrograms sublingual once for small fragments in a stable woman; methylergometrine 0.2 mg oral 8-hourly for 3 days (not in hypertension); tranexamic acid 1 g oral 8-hourly for 3 days; amoxicillin-clavulanate 625 mg oral 8-hourly for 5 to 7 days, or ampicillin 2 g IV 6-hourly plus gentamicin 5 mg/kg IV once daily plus metronidazole 500 mg IV 8-hourly for infection; ferrous sulphate 200 mg oral 8-hourly for 3 months.
• Procedures: manual vacuum aspiration or suction evacuation under ultrasound guidance after the first dose of antibiotics; blunt curettage with care to avoid perforation; hysteroscopic resection of persistent placental tissue; embolisation or hysterectomy for severe bleeding or accreta.
• Special groups: suspected placenta accreta spectrum (tissue deeply adherent or vascular) is managed in a referral facility, as curettage can cause heavy bleeding.
• Red flags: heavy bleeding, fever above 38 degrees Celsius, foul lochia, collapse, vascular mass on Doppler.
• Follow-up: ultrasound at 1 to 2 weeks after evacuation; haemoglobin at 4 weeks; histology review; review at 6 weeks.