Dr. Chapa’s OBGYN Clinical Pearls

The latest guidelines from the CDC on contraception for individuals with obesity are discussed, highlighting key updates due in 2025. There's a deep dive into whether specific birth control methods are contraindicated based on BMI. The podcast dismantles myths about contraceptives causing weight gain, and focuses on various contraceptive options, including the E-tronorgestrel implant. Interestingly, while most methods have little impact on weight, Depo-Provera does stand out as an exception. Tune in for valuable insights on shared decision-making in contraceptive use!

We have made SIGNIFICANT progress in our ability to screen for fetal RH factor using cell free DNA from maternal blood. Cell-free DNA to determine the fetal RHD genotype from the maternal circulation was first described in 1993. We have come so far since them. In March 2024, the ACOG released a Practice Advisory stating, “the use of NIPT to prioritize use of RhIg and conserve RhIg supply is a reasonable consideration”. Two U.S. companies have introduced cell-free DNA assays for RHD as part of their noninvasive prenatal testing assays. These assays use next generation sequencing to determine the presence of fetal RHD DNA. These tests are NEAR perfect in accuracy (we will review the latest data here). So, how can it be possible to detect the RHD gene (when truly present), yet the fetus ultimately be found to have RH negative blood? In other words, how do we explain the occurrence of genotype/phenotype discrepancy? The science is clear. In this episode, we will review this unusual phenomenon and summarize a recent (November 2024) clinical validation study on the use of cell free DNA test testing to look for this “genomic variance”. This article was also on the Green Journal’s “Spotlight on Fetal RHD” on 12/16/2024. Is this common? And which patient population is more likely to have this? Listen in for details.

The saying says, “The Devil is in the details”. This idiomatic phrase that means even the grandest project depends on the success of the smallest components. So is the case with low dose ASA for preeclampsia prevention. Currently, the ACOG states, “Low-dose aspirin (LDA) (81 mg/day) prophylaxis is recommended in women at high risk of preeclampsia and should be initiated between 12 weeks and 28 weeks of gestation (optimally before 16 weeks) and continued daily until delivery” (ACOG CO 743; 2018). But the DOSE of LDA is controversial with mounting data that the minimal dose should be 100mg, with leading commentaries pushing for 162 mgs here in the US. We have covered this MANY times on our show. But there is a separate issue here that is often missed. Does it matter WHEN in the day this is taken? Is taking LDA first time in the morning best? What about after lunch? At bedtime? There is data here to guide us. In this episode, we will review the CHRONOBIOLOGIC response of LDA in pregnancy. Yes, that is a real term! This is also reflected in the March of Dimes data. Plus, there is Level I data supporting the best time to take aspirin- and it is fascinating. Listen in for details.

EVERYTHING CHANGES! So true. And now, the USPSTF has changed (UPDATED) their recommendations for cervical cancer screening in regards to HPV primary screening. This is BRAND NEW, within the last 24 hours. Primary HPV screening for cervical cancer has gained a lot of steam and is progressing quickly. The FDA approval of “dual stain” testing of hrHPV positive results, the recent FDA approval for patient self-collection for HPV vaginal samples in a clinical setting, and now this new draft recommendation from the USPSTF. What did they update? How is that controversial? Listen in for details!

Well, in this episode we have 2 very interesting and challenging clinical situations. These come from real world clinical encounters so we thought we would share these with you because they are brain teasers and should be discussed. They both have to do with OB ultrasound. First, is there a “minimal” CRL to estimate gestational age? In other words, is there a CRL that is too small to be accurate? It’s an intriguing question and we will give an answer! Second, in women with regular and predictable menstrual cycles that are every 21 or 35 days, how to we “reconcile” a CRL EGA since that CRL algorithm is based on a “typical 4-week cycle”? How can we? Should we adjust the sono dating? WE will review in this episode. PLUS, we will review the latest data on how AI can greatly impact gestational age calculation via ultrasound. So, we have 2 questions, and we will give 2 answers (2 x2)…Listen in for details.

Acetaminophen, commonly used during pregnancy, is scrutinized for potential links to ADHD and autism in children. Recent studies spark debate over its safety, while medical organizations remain cautious without altering recommendations. Pregnant women voice concerns about medication use, highlighting the necessity of healthcare guidance. The discussion wraps up with a personal note on relaxation plans, making it a holistic blend of medical insight and personal touch.

In November 2013, ACOG issued the Hypertension in Pregnancy Task Force Report recommending daily low-dose aspirin (81mg) beginning in the late 1st trimester for women with a history of early-onset preeclampsia and preterm delivery at less than 34 0/7 weeks, or for women with more than one prior pregnancy complicated by preeclampsia. The following year, the USPSTF published a similar guideline, although the list of indications for low-dose aspirin use was more expansive. Since then, the ACOG has issued new guidance on low-dose aspirin, in 2018 and 2021. Nonetheless, while criteria for use has evolved, the dosage recommended has remained as 81 mg. But MEDICINE MOVES FAST, and a new Expert Review in the AJOG MFM is making a case for 162mg. Are we underdosing low-dose aspirin for prevention of preeclampsia? A litany of data says YES. Listen in for details.

Egg freezing in your 20s has become a hot topic, fueled by social media anxiety regarding fertility. The shift from viewing fertility loss as a 'cliff' after 35 to a more gradual slope is hotly debated. Misleading marketing creates pressure, leaving many young women feeling behind in their reproductive journey. Experts discuss the ethical concerns of commodifying fertility services while advocating for informed decisions. The complexities of female fertility are unpacked, emphasizing the balance between career aspirations and motherhood.

A senior resident shares a revealing patient encounter that underscores the importance of evidence-based medicine. The discussion dives into the rising trend of elective egg freezing, addressing societal pressures and misconceptions surrounding fertility. An engaging conversation emerges about intimacy during pregnancy, highlighting the need for better sexual education. Personal anecdotes reflect on the anxieties faced by women navigating career ambitions while contemplating their reproductive choices.

In the United States, more than 400,000 babies are born prematurely each year, which is about 1 in 10 babies. Over the last several decades, multiple studies have shown a link between poor oral health and increased occurrence of preterm birth. Researchers have looked at various ways to improve dental health during pregnancy, including doing a “deep-teeth cleaning” (also called ‘scaling and planing’), which involves removing plaque and tarter on the teeth and below the gum line. However, despite improving periodontitis, deep teeth cleaning approaches have not proven to be effective in the prevention of preterm birth. But now new data has discovered an easy and inexpensive way to improve oral health and potentially reduce preterm births. This data was originally presented at the annual Pregnancy meeting at SMFM, but now it is a peer reviewed publication. In this episode, we will review how chewing xylitol gum has promising results for preterm birth reduction. Nonetheless, some important limitations must be reviewed. Listen In for details.