Venous thromboembolism prophylaxis of the obese postpartum patient: A cross-sectional study

Obesity increases risk of venous thromboembolism (VTE) in obstetric patients regardless of delivery mode and for up to six weeks postpartum.

This study aimed to examine postpartum pharmacological VTE prophylaxis practices for obese women at an Australian tertiary referral hospital.

Medical records were retrieved for obese obstetric patients who delivered during May 2016-May 2017. Records were examined for demographic data, VTE risk factors, and LMWH (low-molecular-weight heparin) use. Due to lack of specific Australian or local guidelines, practice was evaluated using recommendations from the Royal College of Obstetricians and Gynaecologists (RCOG-UK). Patients with BMI (body mass index) <30, incomplete/unavailable medical records, and those discharged from other health services were excluded.

One hundred and eight postpartum patients (70 caesareans, 38 vaginal deliveries) with a BMI ≥ 30 kg/m² were reviewed. Of these patients, 53 (49.1%) had a BMI ≥ 40 kg/m² . Ninety-eight of 108 (90.7%) patients had ≥2 VTE risk factors including a BMI ≥ 30 kg/m² . One hundred and three of 108 (95.4%) patients were indicated for postpartum VTE prophylaxis with LMWH, and 77 of 103 (74.8%) patients received it. Three of five patients meeting criteria for ≥6 weeks of LMWH thromboprophylaxis had it prescribed. Of the 72 patients whose weight exceeded 90 kg and who also received LMWH, 32 (44.4%) were prescribed a weight-adjusted dose.

VTE prophylaxis practices using LMWH in obese postpartum patients, including weight-adjusting doses and extended-course prescribing, appear variable. Limited literature, recommendation discrepancies, and varied awareness of recommendations may be contributing factors. Further education and research regarding this high-risk cohort are warranted.