Vision Changes in Pregnancy

Today we are joined by Dr. Ben Young. Ben is an ophthalmology resident at Yale New Haven Hospital in Connecticut, and is sharing with us a common complaint that we know very little about - the eye in pregnancy!

Ben also hosts Eyes For Ears, an educational podcast and flashcard reference for ophthalmology residents. If you happen to know any vision sciences students or residents, let them know about it!

We start out talking about the “ocular vital signs,” which are:
- Visual Acuity
- Pupils (“swinging light test”)
- Intraocular pressure
- Visual Fields
- Extra-ocular movements

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Image copyright of FOAMCast

The most common reasons for ophthalmology issues in pregnancy relate to either 1) vision changes requiring a new prescription, or 2) dry eye. However, don’t forget some key pearls:

- Monocular (single eye) double vision — dry eye. Binocular (both eye) double vision — badness!
- A Snellen chart and a flashlight are the best tools you have to help out a consultant.
- Check out this video on how to perform a swinging flashlight test.

Further reading from the OBG Project:
Get updates on this and more content, as well as other awesome features for FREE if you’re a PGY-4 — sign up for OBG First!
Is Cataract Surgery in Women Associated with Decreased Mortality?

Special SMFM Interview: Dr. William "Bill" Grobman

Today we sit down with Dr. William “Bill” Grobman, Vice Chair of Clinical Operations and Professor in the Department of Obstetrics and Gynecology at Northwestern University Feinberg School of Medicine. Dr. Grobman is the lead author of the ARRIVE trial — and we asked him about it! Take a listen, and hope you enjoy.

Fetal Growth Restriction

FYI — this podcast has been updated with some new information as of 6/27/2021! Check out the update here.

On today’s episode, we tackle the new ACOG PB 204 on fetal growth restriction. There’s quite a bit to cover, so you’ll see today’s episode is a bit longer. We’ve enlisted the help of Chris Nau, MD, an MFM fellow at Brown, to help us through all the recommendations.

FGR, as Chris explains, results from a process where there is mismatch between fetal demands and placental supply of oxygen and nutrients. Symmetric growth restriction arises earlier, and asymmetric growth restriction arises later, with the differentiating factor being asymmetric growth restriction resulting in a larger head circumference : abdominal circumference ratio. The PB 204 goes into many of the common causes, but the list is long!

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ACOG PB 204

ACOG and SMFM state that a sonographic estimated fetal weight less than the 10th percentile is the measurement definition of fetal growth restriction, though as Chris explains, there are a number of limitations to this definition.

Screening is performed using a fundal height at prenatal visits, and if the height is < 2cm discrepant from the gestational age, an ultrasound should be performed. Alternatively ultrasounds can be used primarily, especially with known maternal conditions that might predispose someone to FGR, or if fundal height assessments are difficult.

Once a growth-restricted infant is identified, you should check the due date calculation and make sure it is right! (Check out our previous episode on dating!) Next, re-review the mother’s medical history and pregnancy history, including aneuploidy screening, to date. A level 2 ultrasound may help identify anatomic abnormalities that point to an etiology. And identifying modifiable risk factors, including optimizing medical conditions or smoking cessation, may be worthwhile.

With respect to management, there are variable institutional protocols with respect to monitoring. Umbilical artery velocimetry reduces risk of perinatal death when added to other antenatal testing (i.e., modified BPP). Normal or elevated systolic : diastolic flow ratio does not carry increased risk to the fetus; however absent or reversed end-diastolic flow increases risk for perinatal mortality. Chris reviews our protocol at Brown in the podcast.

Timing of delivery is a tricky one — there is not great evidence, and the newest guidance from PB 204 states that reassuring fetal testing should deliver between 38w0d - 39w6d. If there is FGR plus concerning maternal or fetal findings, delivery should be considered between 32w0d to 37w6d.

When counseling about future pregnancies, there is about a 20% risk of recurrence. At this time, ACOG/SMFM do not recommend baby aspirin for prevention of FGR in the absence of other risk factors for preeclampsia.

Further reading from the OBGProject:
Fetal Growth Restriction: Diagnosis, Evaluation, and Management
Aspirin Treatment - ACOG and USPSTF Recommendations

Hypertension and Pregnancy Trio

We’ve had an overwhelming response to our Espresso episode on acute treatment of severe hypertension in pregnancy, so today we have a special triple episode release on pregnancy and hypertension! We dive into ACOG PB 202 on Preeclampsia and Gestational Hypertension, and ACOG PB 203 on Chronic Hypertension in Pregnancy (membership required for both).

In our first episode, we dive into risk factors and definitions to set the stage. Recall several risk factors that may raise your suspicion for these disorders:
- Nulliparity
- Multiple gestation
- Chronic hypertension
- History of hypertensive disorder of pregnancy in previous pregnancy
- Pregestational or gestational diabetes mellitus
- Thrombophilia, Anti-phospholipid syndrome, or SLE
- Chronic kidney disease
- Advanced maternal age > 35 years
- Obesity (BMI > 30) or obstructive sleep apnea
- Conception via assisted reproductive technology

In episodes 2 and 3, we dive into the specific definitions and management for each hypertensive disorder. Here are our show notes in table format; we hope that this helps you with your own review!

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And in closing, a few postpartum/future health pearls to consider:
- With a history of any of these hypertensive disorders, baby aspirin is indicated in future pregnancies beginning at 12 weeks gestation to reduce risk or delay onset of preeclampsia.
- Women with a history of preeclampsia have 3-4x higher lifetime risk of hypertension, and 2x lifetime risk of heart disease and stroke, thus its important to ask about these even with just the annual physical.
- Best available evidence suggest NSAIDs are OK to use postpartum for patients with hypertensive disorders of pregnancy.
- Best available evidence also supports use of parenteral magnesium for seizure prophylaxis in patients who develop any of these disorders during the postpartum period (generally onsets within first week, but has been reported up to 8 weeks after delivery!).

Further reading from the OBG Project:
And get updates on this and more content, as well as other awesome features for FREE if you’re a PGY-4 — sign up for OBG First!
Diagnosing Preeclampsia: Key Definitions and ACOG Guidelines
ACOG Preeclampsia Guidelines: Antenatal Management and Timing of Delivery
Aspirin Treatment for Women at Risk for Preeclampsia: ACOG and USPSTF Guidelines
Chronic Hypertension in Pregnancy: Diagnosis and BP Measurement
Chronic Hypertension in Pregnancy: Evaluation and Management
The 2017 AHA/ACC Blood Pressure Guidelines
#GrandRounds: Does Hypertension in Pregnancy Predict Hypertension in Later Life?

Special SMFM Interview: Dr. George Saade

Our first special interview from SMFM is with Dr. George Saade. Dr. Saade is the Jennie Sealy Smith Distinguished Chair, Chief of Obstetrics and Maternal Fetal Medicine, and Professor of Obstetrics and Gynecology and Cell Biology at the University of Texas Medical Branch in Galveston, TX. His official bio can be found at this link.

Dr. Saade shared with us a number of great pearls, including his philosophy on pregnancy as a window to future health. We hope you enjoy and look forward to our next interview coming next Wednesday!