Podcast Summary: Dr. Chapa’s OBGYN Clinical Pearls

Episode: Alex’s Input: Aspirin’s Awkward Acumen

Date: February 18, 2026
Host: Dr. Chapa
Guest Voice Note: Alex

Episode Overview

This episode centers on the evolving evidence regarding low-dose aspirin to prevent hypertensive disorders of pregnancy, specifically preeclampsia. Dr. Chapa addresses a listener’s (Alex) insightful question about apparent discrepancies between two recent studies—one from UT Southwestern (Parkland Hospital) and another randomized controlled trial (RCT) published in the Green Journal (Jan 2026)—each comparing aspirin doses of 162mg versus 81mg. The discussion highlights the complexities in interpreting research findings, universal versus risk-based dosing approaches, differences in study outcomes, and practical clinical implications.

Key Discussion Points & Insights

1. Setting the Stage: The Power of the Podcast Community

• Dr. Chapa opens by praising the podcast’s engaged and informed audience, underscoring how listener input drives deeper, evidence-based conversations.
  • Notable quote:
    “Our podcast family members … know the data and they're good guys. They're good.” (00:52)

2. The Listener's Challenge: Reconciling Contradictory Data

• Alex, a podcast listener, submits a voice message after an episode about SMFM 2026 data, questioning the conflicting results between:
  • The UT Southwestern (Parkland) cohort study (SMFM abstract) favoring 162mg aspirin, and
  • The Green Journal RCT (Jan 2026), which found no significant difference between 81mg and 162mg doses.
• Alex asks:

  “How do you reconcile these findings and what factors do you think most likely explain the discrepancy?” (02:11)

3. Dr. Chapa’s Recap of the UT Southwestern (Parkland) Study (SMFM 2026)

• Design: Not an RCT—compared cohorts separated by time (pre/post protocol change).
• Population: Universal approach—everyone received 162 mg, not just those at high risk.
• Findings:
  • 29% reduction in preeclampsia with severe features across high-risk categories (including those with chronic hypertension).
  • Decreased rates of all gestational hypertensive disorders.
  • No increased rates of placental abruption or neonatal bleeding.
• Notable feature: Universal (not just risk-based) 162mg dosing.
• Quote:

  “This was a win. This thing worked … Even in women with chronic hypertension, they also reduced the rates of preeclampsia with severe features.” (05:09)

4. The Contrasting RCT (Green Journal, Jan 2026)

• Design: True RCT, multi-center (Cornell, UPenn, Miami), included only patients with ACOG-defined high risk of preeclampsia.
• Findings:
  • Preterm preeclampsia/severe features: 14.1% in 162mg group vs. 17.1% in 81mg, not statistically significant (p=0.4).
  • Important caveat: 8 placental abruptions in the 162mg group, 0 in 81mg group.
• Dr. Chapa’s analysis:
  • While not statistically significant, there was a numerical reduction (~3%). He suggests sometimes “the math wasn’t mathing” due to possible power issues.
  • Placental abruption finding is notable but could be a chance (“quinky dink”) since abruptions are rare and the study wasn’t powered to analyze such infrequent outcomes.
• Memorable quote:

  “I would love it to be both clinically and statistically significant. But in cases where they're discrepant, I'll take some clinical significance, knowing that the math may have to do with the total study numbers and power calculations.” (08:00)

  • And on abruption finding:

    “I can’t explain that, and the authors can’t either… it needs further study.” (10:34)

5. Reconciling the Discrepancy: Study Design & Population Differences

• Universal (UTSW) vs. Risk-based (RCT) Protocols:
  • UTSW included all pregnant patients (universal), potentially broadening and amplifying observed benefits.
  • RCT included only those with ACOG-defined high risk factors, excluding those with several moderate risk factors.
  • This design difference narrows the pool in the RCT and could reduce the observed efficacy.
• Population Characteristics:
  • High-risk patients (those at increased risk of preeclampsia) inherently have higher risk for abruption—makes assessing aspirin-specific bleeding risk tricky.
• Dose-response effect:
  • Dr. Chapa references meta-analyses supporting a dose-dependent benefit of aspirin (>100mg), but evidence on bleeding risk (from higher dose) remains mixed and less robust.

Quotes:

• On population selection:

  "This is obvious distinction here is that in the UT Southwestern publication, everybody got it. Whereas in this RCT it was only in patients who had the ACOG defined high risk factors, one or more. Okay, so that limits the pool, potentially limit, therefore the benefit." (13:17)

• On the limitations of RCT bleeding findings:

  “It would have been nice to … stratify everything, if aspirin is a standalone risk factor. But they couldn’t because they didn’t have enough power to look for these rare occurrences.” (10:56)

6. Dr. Chapa’s Practical Guidance & Takeaways

• Universal aspirin probably helps:
  • 81mg dose is “fine,” universal application is valuable.
• 162mg may be better, particularly for high-risk patients:
  • “Not that worried” about bleeding risk, since bulk of evidence hasn’t shown consistent increased bleeding with higher dose.
  • Still, the measured/“conservative media in the middle” approach would be:
    • Universal 81mg for all,
    • 162mg for those at high risk.
• On evolving medicine:
  • “This is why medicine keeps evolving. That’s why you got to keep doing the data and look at the holistic nature of the evidence.” (10:11)
• Final nod to Alex:

  “Alex, great job, brother. Thank you for sending us that message. True to form, we actually pay attention…” (16:10)

Notable Quotes & Timestamps

• On how studies differ:

  “The UT Southwestern publication was universal. … In this RCT from the Green Journal … only included patients who had, quote, high risk factors for preeclampsia.” (13:17)

• On universal approach:

  “The second thing is that while this randomized trial used the risk factors and the other study used universal, there’s a bigger capture with the universal, thereby potentially allowing more clinical significance.” (14:08)

• On clinical vs. statistical significance:

  “I’ll take some clinical significance, knowing that the math may have to do with the total study numbers and power calculations.” (08:00)

• On the rare outcome of abruption in the RCT:

  “It’s a quinky dink, as they say themselves. I don’t know. We found eight. We don’t have enough power to figure it out. Needs further study.” (11:26)

Timestamps for Key Segments

• 00:08: Dr. Chapa sets up the episode and the critical question about aspirin dosing
• 02:11: Alex’s question, laying out the conflicting studies
• 03:05 – 06:30: Dr. Chapa recaps the UTSW cohort study and its findings
• 06:31 – 10:34: Dr. Chapa breaks down the RCT’s methodology and divergent results
• 10:34 – 14:10: Analysis of the discrepancies—differences in design, populations, and clinical implications
• 14:11 – 17:15: Dr. Chapa’s takeaway recommendations; concluding remarks

Summary Table: Comparison of Key Studies

| Aspect | UTSW Cohort Study (SMFM 2026) | Green Journal RCT (Jan 2026) | |--------------------------------------------|-------------------------------|-------------------------------| | Design | Cohort, pre/post (not RCT) | Randomized Controlled Trial | | Population | Universal (all comers) | High-risk by ACOG only | | Aspirin Dose Compared | 162 mg vs. 81 mg | 162 mg vs. 81 mg | | Preeclampsia Reduction | 29% (all hypertensive disorders) | 3% (14.1% vs 17.1%; not statistically significant) | | Effect in Chronic Hypertension | Yes, reduced rates | Not highlighted | | Abruption/Bleeding Events | No increase | 8 abruptions (162mg) vs 0 (81mg) | | Conclusion | Strong benefit, no excess harm | Modest effect, bleeding signal (not conclusive) |

Bottom Line

• Higher dose aspirin (162mg) may confer a dose-related benefit, especially in a universal, all-comers approach—but robust data are still limited.
• RCT data for high-risk-only populations show less dramatic benefits, and isolated signals for increased bleeding (abruption) need further study and may be underpowered.
• Approach should weigh broad, practical benefits against rare but severe potential harms; evolving evidence supports continuing inquiry and individualized decision making.

For clinicians:

• Universal 81mg remains reasonable; consider 162mg for those at higher risk if comfortable with available evidence.
• Stay updated—medicine is rarely straightforward, and practice should reflect the totality of nuanced, evolving evidence.

Host sign-off (Dr. Chapa):

“Short of it is different populations, different design. I am a fan of 160mg. I think it works. I'm not that worried about the bleeding. I'm just not.” (16:02)