Stopping Aspirin 2 Days Before Cesarean Delivery and Blood Pressure Effects
Stopping aspirin only 2 days before Cesarean delivery is not recommended and may adversely affect blood pressure control, particularly in women at risk for or with preeclampsia. The evidence strongly supports continuing low-dose aspirin until delivery rather than stopping it prematurely.
Primary Recommendation Based on Guidelines
Low-dose aspirin should be continued daily until delivery in pregnant women taking it for preeclampsia prevention, according to the American College of Obstetricians and Gynecologists 1, 2, 3. This recommendation is supported by multiple international guidelines from Canada, Ireland, New Zealand, the USA, and the UK 1.
Why Stopping 2 Days Before Is Problematic
Blood pressure control may be compromised: Research demonstrates that aspirin has significant blood pressure-lowering effects in pregnant women at risk for preeclampsia, with reductions of up to 9.7/6.5 mm Hg in 24-hour mean systolic/diastolic blood pressure 4. These effects disappear when aspirin is discontinued 4.
Preeclampsia risk persists through delivery: The rationale for continuing aspirin through delivery is that preeclampsia risk continues throughout pregnancy and even into the early postpartum period, with eclamptic seizures potentially developing for the first time after delivery 1.
Postpartum hypertension may increase: Prenatal low-dose aspirin use is associated with significantly lower incidence of postpartum hypertension (0% vs. 22%, p=0.007) in preeclamptic patients 5. Stopping aspirin prematurely removes this protective effect.
Context-Specific Guidance
For Women with Preeclampsia or High Risk
- Do not stop aspirin before Cesarean delivery 1, 2, 3
- Antihypertensive treatment should be continued during labor and delivery to keep systolic BP <160 mmHg and diastolic BP <110 mmHg 6
- The protective effects of aspirin on blood pressure are lost when discontinued, and these effects were present at the time of delivery in clinical trials 4, 7
For Women with Myeloproliferative Neoplasms (Special Population)
The only guideline recommending aspirin discontinuation before delivery applies to a very specific population: women with myeloproliferative neoplasms (polycythemia vera, essential thrombocythemia). In this unique context, aspirin should be stopped 1-2 weeks prior to delivery due to bleeding risk considerations specific to these hematologic conditions 6.
Safety Profile of Continuing Aspirin
Low-dose aspirin (75-81mg) does not increase risks when continued until delivery 1:
- No increased placental abruption risk
- No increased postpartum hemorrhage risk
- No increased fetal intracranial bleeding risk
- No increased perinatal mortality
Common Pitfalls to Avoid
Do not stop aspirin at 36 weeks or 2 days before delivery "just to be safe": This removes protection during a high-risk period and is not evidence-based 1
Do not confuse low-dose aspirin (75-81mg) with high-dose aspirin: The FDA warning about aspirin in the third trimester refers to high doses (>100mg), not prophylactic low doses 1
Recognize that blood pressure effects are time-dependent: The blood pressure-lowering effects of aspirin are markedly dependent on timing of administration and disappear at puerperium when discontinued 4
Blood Pressure Management During Cesarean
For women requiring Cesarean delivery while on aspirin prophylaxis:
- Continue aspirin until delivery 1, 2, 3
- Maintain blood pressure control with antihypertensive medications as needed to keep BP <160/110 mmHg 6
- First-line agents for acute severe hypertension include IV labetalol, oral nifedipine, and IV hydralazine 8
- Vaginal delivery should be considered for women with hypertensive disorders unless Cesarean is required for obstetric indications 6