Pelvic Inflammatory Disease in Pregnancy

Pelvic inflammatory disease in pregnancy is upper genital tract infection (endometritis, salpingitis, tubo ovarian abscess) that is uncommon after the first trimester because the cervical mucus plug and fused decidua block ascent. It occurs mostly before 12 weeks, but can complicate any stage.

• Organisms: Neisseria gonorrhoeae, Chlamydia trachomatis, anaerobes, Gardnerella, enteric gram negative bacilli, streptococci.
• Risk factors: untreated STIs, HIV, recent uterine instrumentation (including abortion), multiple partners.

Lower abdominal pain, fever, vaginal discharge, cervical motion tenderness and adnexal tenderness; nausea and vomiting; peritonism in severe disease.

• Pregnancy may mask or mimic symptoms.
• Differential diagnosis: ectopic pregnancy, septic miscarriage, appendicitis, pyelonephritis, ovarian torsion or cyst accident, degenerating fibroid, chorioamnionitis, diverticulitis, urinary tract infection, inflammatory bowel disease.
• Complications: miscarriage, preterm labour, chorioamnionitis, intrauterine infection, maternal sepsis, tubo ovarian abscess rupture, peritonitis, fetal death, long term infertility and chronic pelvic pain.

Clinical diagnosis with exclusion of ectopic pregnancy.

• Obstetric ultrasound for intrauterine pregnancy and viability; pelvic ultrasound for adnexal masses and abscess.
• Full blood count, CRP, blood cultures, urinalysis and culture, urine pregnancy test, endocervical NAAT for gonorrhoea and chlamydia, HIV and syphilis tests, lactate.
• CT or MRI (without gadolinium) if diagnosis is unclear.

Hospital admission with parenteral therapy that is safe in pregnancy.

• Supportive: admission, IV fluids, analgesia (paracetamol 1 g, morphine 2.5 to 5 mg IV if needed), antiemetics (ondansetron 4 mg or metoclopramide 10 mg), fetal monitoring, thromboprophylaxis if immobile, partner treatment.
• Pharmacological: ceftriaxone 2 g IV once daily plus azithromycin 500 mg IV or orally once daily plus metronidazole 500 mg IV every 8 hours; doxycycline is avoided. Alternative: clindamycin 900 mg IV every 8 hours plus gentamicin 5 mg/kg IV once daily. Change to oral therapy 24 to 48 hours after clinical improvement: azithromycin 500 mg daily with metronidazole 400 mg twice daily to complete 14 days. Abscess: continue IV therapy and consider drainage.
• Procedures: percutaneous or laparoscopic drainage of tubo ovarian abscess; laparotomy for rupture or failure; obstetric management of preterm labour or chorioamnionitis (delivery as indicated).
• Special groups: pregnancy, avoid doxycycline, tetracyclines and quinolones; HIV, give the full regimens and start antiretroviral therapy early; second and third trimester, steroids for fetal lung maturity if preterm delivery is expected; penicillin allergy, clindamycin with gentamicin.
• Red flags: peritonism, high fever, hypotension, vaginal bleeding, signs of rupture or abscess, preterm contractions, fetal distress.
• Follow-up: daily review during admission; repeat ultrasound for abscess at 48 to 72 hours; test of cure for chlamydia and gonorrhoea at 3 to 4 weeks; antenatal surveillance for growth and preterm labour.