This Week in Obstetrics & Gynecology — Sep 17, 2026

Welcome to This Week in Obstetrics and Gynecology. This week we're covering 10 notable papers spanning procedural pain and infection prevention, long-term maternal and fetal medicine, menopause and hormone therapy, and gynecologic oncology. Let's dive in.

We start with two papers about making routine procedures less painful and less risky, both published in JAMA. Elgemark and colleagues ran a multicentre, double-blind, placebo-controlled randomized trial across eleven Swedish outpatient clinics, enrolling 370 nulliparous individuals between eighteen and thirty-one years old who had chosen a small-diameter intrauterine device [1]. Two minutes before placement, participants received either ten millilitres of mepivacaine at twenty milligrams per millilitre, or saline, instilled into the uterine cavity through a hydrosonography catheter. Pain during placement fell by about fifteen millimetres on a hundred-millimetre visual analogue scale, from just under sixty in the placebo group to around forty-four with mepivacaine, and that difference held after adjusting for the individual clinician. Almost every patient in the mepivacaine group described the pain as tolerable, just over ninety-eight percent, compared with about ninety-one percent on placebo, which works out to treating roughly fifteen patients to make one more person's experience tolerable. This is a meaningful, simple, low-cost intervention in exactly the population where fear of pain most often deters IUD uptake, and it uses equipment most gynecology clinics already stock.

Staying with JAMA, Freret and colleagues asked a different question: when a landmark trial tells us to do something, do we actually do it? Using Epic Cosmos data on more than 1.6 million births from 2013 through 2024, they performed a difference-in-differences analysis, treating cesarean birth as the exposed group and vaginal birth as the control, with the 2016 publication of the adjunctive azithromycin trial as the inflection point [2]. Before 2016, azithromycin was given at about two percent of unscheduled cesarean births; afterwards, close to forty percent. Over the same period, postpartum infection after cesarean delivery fell, with a difference-in-differences estimate of about two percentage points relative to vaginal birth. That is real-world corroboration of trial efficacy, but it also means roughly sixty percent of eligible unscheduled cesareans in this very large United States cohort still are not getting azithromycin. If your unit does not have it embedded in the intrapartum cesarean order set, that is the actionable gap.

Infection prevention carries over to the perineum. In the American Journal of Obstetrics and Gynecology, Perslev and colleagues reported a secondary analysis of the Danish REPAIR randomized trial, pooling 442 women with second-degree tears or episiotomy into a single cohort [3]. Nearly thirteen percent developed a clinically relevant wound complication. Prolonged active second stage and a deep tear each roughly doubled the odds, and doctor involvement in suturing was associated with about two and a half times the odds, which the authors themselves attribute in part to residual confounding by tear complexity rather than to operator skill. Prophylactic amoxicillin-clavulanic acid cut the odds of complication by roughly two thirds. Notably, episiotomy was not independently associated with wound complications once other factors were accounted for. This is exploratory work, so the practical message is about targeted follow-up: a woman with a long second stage and a deep second-degree tear deserves a proactive postpartum wound check rather than waiting for her to call.

Our second theme is the long shadow that pregnancy events cast over later health, and how we counsel around uncertainty. Also in the American Journal of Obstetrics and Gynecology, Henricks and colleagues followed 718 individuals identified in early pregnancy between 2000 and 2003 with subclinical hypothyroidism, thyroid peroxidase antibodies, or both, at a single tertiary public health system, with a median follow-up of about twenty-one years and up to twenty-five [4]. About a third OF PARTICIPANTS progressed to overt hypothyroidism. The phenotype mattered a great deal: among those with both subclinical hypothyroidism and positive antibodies, just over half OF THOSE WOMEN progressed, and they progressed fastest, compared with roughly a quarter to just under thirty percent for either abnormality alone. In a nested matched comparison, women with antenatal thyroid abnormalities developed overt hypothyroidism at nearly three times the rate of normothyroid controls, about twenty-nine percent versus ten percent. The practical implication is that an incidental antenatal thyroid abnormality is not a transient pregnancy curiosity; it is a marker for decades of risk, and the dual-abnormality phenotype in particular warrants a documented long-term surveillance plan handed off to primary care.

Two other papers in this theme deal with how we classify and how we choose. Mari contributes an expert review in the American Journal of Obstetrics and Gynecology on twin-twin transfusion syndrome and related monochorionic disorders, arguing that inconsistent polyhydramnios definitions, heterogeneous Doppler findings grouped within the same Quintero stage, and unrecognized overlap with twin anemia-polycythemia sequence and selective growth restriction are why outcomes are so hard to compare across fetal therapy centres [5]. The proposed framework integrates placental vascular anatomy, Doppler findings, and overlap phenotypes alongside Quintero staging; the author is explicit that it is complementary and hypothesis-generating, not prescriptive, and that prospective validation is needed. Then in Obstetrics and Gynecology, Jacobs and colleagues make a pointed ethical argument about low-titer group O whole blood in prehospital trauma resuscitation [6]. Whole blood is usually RhD-positive because RhD-negative units are scarce, and transfusing it into an RhD-negative patient with reproductive potential risks anti-D alloimmunization and hemolytic disease of the fetus and newborn years later. The justification for accepting that risk rested on a survival advantage, and two recently published randomized trials of prehospital traumatic hemorrhage found no survival advantage for whole blood over component therapy. The authors therefore conclude that RhD-positive whole blood is ethically unjustifiable for these patients when compatible products are available, and recommend defaulting patients with reproductive potential to RhD-negative products until type is confirmed, with guaranteed cost-free follow-up when an incompatible transfusion does occur. If you sit on a transfusion or trauma committee, that is a protocol conversation worth starting.

Our third theme is menopause and perimenopause, with two clinical perspectives in Obstetrics and Gynecology. Wong and Kotsopoulos revisit menopausal hormone therapy after risk-reducing salpingo-oophorectomy in women with hereditary breast and ovarian cancer syndrome, who are advised to undergo surgery five to fifteen years before natural menopause [7]. Uptake of hormone therapy in this group remains suboptimal, which the authors attribute largely to misinformation about breast cancer risk, and they summarize the evidence in BRCA1 and BRCA2 carriers while flagging their intention to evaluate conjugated estrogen combined with bazedoxifene as a formulation that might treat symptoms and protect bone while potentially lowering breast cancer risk. That last part is a hypothesis, not a result, so counsel accordingly. Alongside it, Piasta and Zewail offer a practical toolkit for perimenopause, a stage that is variably defined and largely guideline-orphaned, covering hormonal contraceptives as symptom management, alternative hormonal strategies for patients in whom contraceptives are inadequate or unwanted, and how to individualize through shared decision making while accounting for contraceptive need and evolving cardiometabolic risk [8].

Finally, gynecologic oncology. Keymeulen and colleagues, in the American Journal of Obstetrics and Gynecology, analysed more than 210,000 patients with stage one to three endometrial cancer undergoing upfront minimally invasive hysterectomy in the National Cancer Database from 2012 to 2023 [9]. Laparotomy conversion fell over the twelve years in both groups, and after propensity weighting, robotic-assisted hysterectomy was associated with about a seventy-eight percent lower conversion rate than conventional laparoscopy, roughly one and a half percent versus six percent. Unplanned readmission and thirty-day perioperative mortality were also modestly lower with the robotic approach. Tumour size was the dominant driver, with conversion rising above about five centimetres for robotic and four centimetres for laparoscopic surgery, and every high-conversion pattern involved conventional laparoscopy with tumours of six centimetres or more. This is observational, with acknowledged potential confounding by surgeon, but it is useful for consenting and for planning the large-uterus case. And in Gynecologic Oncology, Grisham and colleagues report two-year follow-up of the RAMP 201 phase two study of avutometinib plus defactinib in 115 patients with recurrent low-grade serous ovarian cancer [10]. Median duration of response was about thirty-one months overall and in KRAS-mutant disease, with progression-free survival close to thirteen months overall and about twenty months in KRAS-mutant patients. Grade three or higher creatine phosphokinase elevation occurred in about a quarter OF PATIENTS, twelve percent discontinued for adverse events, and there were no treatment-related deaths or new safety signals.

If you only have time for one paper this week, make it the mepivacaine IUD trial in JAMA [1]. It is a properly blinded, multicentre randomized trial of a cheap intervention that addresses the single biggest barrier nulliparous patients cite to choosing an intrauterine device, and you could implement it in clinic next week.

Here are the key takeaways from this week in Obstetrics and Gynecology. Intrauterine mepivacaine before IUD placement in nulliparous patients meaningfully reduces pain and makes the procedure tolerable for almost everyone. Adjunctive azithromycin for unscheduled cesarean has been adopted in about forty percent of cases in the United States with a measurable fall in postpartum infection, so check your order sets for the remaining gap. After a second-degree tear or episiotomy, a prolonged second stage and a deep tear should trigger proactive wound follow-up, and prophylactic antibiotics were protective in the Danish cohort. An antenatal thyroid abnormality, especially subclinical hypothyroidism with positive peroxidase antibodies, predicts roughly triple the long-term risk of overt hypothyroidism, so hand off a surveillance plan. And with no survival advantage for whole blood in two prehospital trauma trials, patients with reproductive potential should default to RhD-negative products where available.

That's your roundup for This Week in Obstetrics and Gynecology. The full transcript and references are available on the episode page in your AudioScholar library. This is an AI-curated summary — for clinical decisions, always consult primary sources and current guidelines. See you next week.

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This is an automated summary generated by artificial intelligence, which can make mistakes. Always review the original source materials.