Dr. Chapa’s OBGYN Clinical Pearls

Welcome back, everyone. Today we're diving into one of the most hotly debated topics in obstetrics- should we be treating preeclampsia without severe features with antihypertensive medications during expectant management? Now, if you've been following the literature- and our show, you know that the landmark CHAP trial changed the game for chronic hypertension in pregnancy. It showed us that targeting a blood pressure below 140 over 90 reduces serious maternal complications, without harming the baby. That was a big deal. But here's the thing, CHAP studied chronic hypertension. Then there was the CHIP trial- that also found that tight control of gestational hypertension and nonproteinuric chronic hypertension was also beneficial. These did not address preeclampsia without severe features, and yet, the ripple effects of that trial have sparked a global conversation about whether we should be extending those same treatment principles to women with preeclampsia who don't yet have severe features. And this is where it gets really interesting, because the guidelines don't agree. In the United States, ACOG and the Society for Maternal-Fetal Medicine still say: hold off on antihypertensives unless blood pressures hit the severe range at 160/110. But step outside the US, and you'll find the World Health Organization, the International Society for the Study of Hypertension in Pregnancy, FIGO, NICE, and Hypertension Canada all recommending treatment at 140 over 90, regardless of whether the diagnosis is chronic hypertension, gestational hypertension, or preeclampsia. So who's right? And more importantly what does this mean for the patient sitting in front of you right now, at 34 weeks, with a blood pressure of 150 over 95, some proteinuria, but no severe features? Today, we're going to break this down. We'll review the controversy, walk through the divergent guidelines, and most importantly talk about the real, practical implications that favor treating these patients during expectant management. Because when you're watching someone with preeclampsia, waiting for the right time to deliver, there's a strong argument that controlling their blood pressure isn't just reasonable…may be protective. So grab your coffee, settle in, and let's get into it.
1. Society for Maternal-Fetal Medicine Statement: Antihypertensive Therapy For mild chronic Hypertension in Pregnancy-The Chronic Hypertension And Pregnancy Trial. American Journal of Obstetrics and Gynecology. 2022. Society for Maternal-Fetal Medicine; Publications Committee.
2. Preeclampsia. The New England Journal of Medicine. 2022. Magee LA, Nicolaides KH, von Dadelszen P.

3. Antihypertensive Drug Therapy for Mild to Moderate Hypertension During Pregnancy.The Cochrane Database of Systematic Reviews. 2018. Abalos E, Duley L, Steyn DW, C.
4. Prevention and Treatment of Maternal Stroke in Pregnancy and Postpartum: A Scientific Statement From the American Heart Association. Stroke. 2026. Miller EC, Bello NA, Chen PR, et al.
5.Hypertension in Pregnancy: Diagnosis, Blood Pressure Goals, and Pharmacotherapy: A Scientific Statement From the American Heart Association. Hypertension. 2022. Garovic VD, Dechend R, Easterling T, et al.

The American College of Obstetricians and Gynecologists (ACOG) does not recommend routine ultrasound measurement of the lower uterine segment (LUS) thickness as part of the evaluation for trial of labor after cesarean delivery (TOLAC). ACOG Practice Bulletin No. 205 (2019) on Vaginal Birth After Cesarean Delivery does not include LUS measurement among its recommendations for TOLAC candidacy assessment. The guideline focuses on clinical factors such as type of prior uterine incision, number of prior cesarean deliveries, and other obstetric history to determine TOLAC candidacy, and emphasizes that most women with one previous low-transverse cesarean delivery should be counseled about and offered TOLAC. But what if you find a likely uterine window at the LUS? Does that mandate a repeat C-section? This topic comes from Serena, one of our podcast family members. Listen in for details.
1. Dr. Chapa’s Clinical Pearls, Dec 31., 2023: LUST FOR TOLAC; and follow up episode Jan 15, 2024
2. ACOG Practice Bulletin No. 205: Vaginal Birth After Cesarean Delivery. Committee on Practice Bulletins—Obstetrics Obstetrics and Gynecology. 2019;133(2):e110-e127. doi:10.1097/AOG.0000000000003078.
3. Rozenberg P, Sénat MV, Deruelle P, et al. Evaluation of the Usefulness of Ultrasound Measurement of the Lower Uterine Segment Before Delivery of Women With a Prior Cesarean Delivery: A Randomized Trial. American Journal of Obstetrics and Gynecology. 2022.
4. Swift BE, Shah PS, Farine D. Sonographic Lower Uterine Segment Thickness After Prior Cesarean Section to Predict Uterine Rupture: A Systematic Review and Meta-Analysis. Acta Obstetricia Et Gynecologica Scandinavica. 2019.
5. McLeish SF, Murchison AB, Smith DM, et al. Predicting Uterine Rupture Risk Using Lower Uterine Segment Measurement During Pregnancy With Cesarean History: How Reliable Is It? A Review. Obstetrical & Gynecological Survey. 2023.
6. Jastrow N, Demers S, Chaillet N, et al. Lower Uterine Segment Thickness to Prevent Uterine Rupture and Adverse Perinatal Outcomes: A Multicenter Prospective study.
7. American Journal of Obstetrics and Gynecology. 2016.
8. Guerby P, Bujold E, Chaillet N. Impact of Third-Trimester Measurement of Low Uterine Segment Thickness and Estimated Fetal Weight on Perinatal Morbidity in Women With Prior Cesarean Delivery. Journal of Obstetrics and Gynaecology Canada. JOGC. 2022.

Should patients check their own urine protein at home when they have a gestational hypertension DX? After all, home-based BP monitoring is an established part of HDP care. Is there data on home urine protein dipstick tests in gestational hypertension? What do professional guidelines say? And what are the pros and cons of home self-monitoring of urine protein? Thank you, SJ, for the podcast topic suggestion. FListen in for details.
1. ACOG PB 222
2. Jayawardena L, Mcnamara E. Diagnosis and Management of Pregnancies Complicated by Haemolysis, Elevated Liver Enzymes and Low Platelets Syndrome in the Tertiary Setting.Internal Medicine Journal. 2020.
3. Tucker KL, et al. (2022). "Effect of self-monitoring of blood pressure on diagnosis of hypertension during higher-risk pregnancy: the BUMP 1 randomized clinical trial. JAMA
4. Chappell LC, et al. (2022). "Effect of self-monitoring of blood pressure on blood pressure control in pregnant individuals with chronic or gestational hypertension: The BUMP 2 Randomized Clinical Trial. JAMA
5. UDIP (Urinary Dipstick In Pregnancy) trial. 2022 May 12;129(13):2142–2148. doi: 10.1111/1471-0528.17180

The vast majority of the time, “community standard of care” reflects evidence-based recommendations. This means that both the predominance of clinical data and what is clinically practice align one with another period but at times, clinical standard practice doesn't always align with what the data shows. How is this possible? This is exactly the case for home blood pressure monitoring in pregnancy (HBPM). This episode idea comes from an OB PGY-3, soon PGY-4, who asked his attending this brilliant question: “If the BUMP1 and BUMP2 clinical trials did not show a benefit with HBPM, why are we still doing it?” That is a complicated question that has a solid answer! Unsatisfied with his response, he asked for our opinion. Listen in for details.
1. Tucker KL, et al. (2022). "Effect of self-monitoring of blood pressure on diagnosis of hypertension during higher-risk pregnancy: the BUMP 1 randomized clinical trial. JAMA
2. Chappell LC, et al. (2022). "Effect of self-monitoring of blood pressure on blood pressure control in pregnant individuals with chronic or gestational hypertension: The BUMP 2 Randomized Clinical Trial. JAMA
3. SMFM Special Statement (2023): Society for Maternal-Fetal Medicine Special Statement: Telemedicine in obstetrics—quality and safety considerations; AJOG

Outside of pregnancy, guidelines emphasize diabetes self-management education and support to facilitate informed decision making, self-care behaviors, problem solving, and active collaboration with health care professionals. This includes, in those with good health literacy, the concept of patient-led self-titration of basal insulin results which has data that it improves glycemic management compared with clinician-led titration for type 2 diabetes among nonpregnant adults. But what about for GDM? Can patient’s self manage their BASAL insulin? In this episode, we will review a new RCT published in April 2026 in the Green Journal on this very subject. As novel as this is, it is not the first to report on this as it was also published (retrospective study in the UK) in 2022. This is a novel approach to insulin in GDM but there are some questions that remain. Listen in for details.
1. Boonpattharatthiti K, Wechkunanukul K, Mayang N, et al . Comparison of Insulin Titration Strategies for Glycemic Control in Type 2 Diabetes: A Systematic Review and Network Meta-Analysis.Diabetes Care. 2025.
2. Valent, Amy M. DO, MCR; Barbour, Linda A. MD, MSPH. Insulin Management for Gestational and Type 2 Diabetes in Pregnancy. Obstetrics & Gynecology 144(5):p 633-647, November 2024. | DOI: 10.1097/AOG.0000000000005640
3. Wang, Xiao-Yu MD; Gabbe, Steven MD; Landon, Mark B. MD; Venkatesh, Kartik K. MD, PhD et al. Patient-Led Insulin Titration for Glycemic Management With Gestational Diabetes Mellitus: A Randomized Controlled Trial. Obstetrics & Gynecology 147(4):p 501-509, April 2026.
4. McGovern AP, Hirwa KD, Wong AK, et al. Patient-led rapid titration of basal insulin in gestational diabetes is associated with improved glycaemic control and lower birthweight. Diabet Med. 2022;39:e14926. doi: 10.1111/dme.14926