Research spotlight: Khaled Fathy

Four out of five women treated for placenta accreta spectrum at two hospitals in Egypt and Saudi Arabia did not have placenta previa, the condition obstetric teams train to recognize first. Yet the group with previa — one of every five cases — bled more, needed more blood, delivered earlier, and sent more newborns to intensive care.

That split comes from a comparative cohort study by Khaled Fathy and colleagues at Zagazig University, published in the Zagazig University Medical Journal. The work tracked 375 pregnancies planned for delivery after 28 weeks. Why it matters right now is straightforward: placenta accreta spectrum, or PAS, is climbing worldwide as cesarean section rates keep rising, and the variant without previa is the one most likely to be missed until the operating room.

For a reader who does not spend time in a delivery room, PAS is velcro gone wrong. After birth, the placenta should peel away from the uterine wall like a bandage coming off. In PAS, the placental tissue has rooted into or through the uterine muscle, so pulling at it can start a hemorrhage measured in liters. Previa is different: it is a location problem, where the placenta covers the cervical opening, forces a cesarean delivery, and adds its own risk of bleeding.

The two conditions overlap for a reason. Previa puts the placenta at the bottom of the uterus, right where previous cesarean scars live, and those scars are where abnormal attachment takes hold most easily. The spectrum itself runs from accreta — attachment to the muscle surface — to increta, invasion into the muscle, and then to percreta, which can breach the uterine wall altogether and reach neighboring organs such as the bladder.

Each cesarean leaves a seam in the uterine wall where the lining is thinner. When the next pregnancy implants near that seam, as happens in many previa cases, the placenta’s anchoring cells push deeper than they should. That is why a prior cesarean is the strongest single risk factor for the previa-plus-PAS combination and why rising cesarean rates keep pushing these numbers upward.

What the numbers show

The researchers compared 63 PAS cases with placenta previa against 312 without it across Zagazig University Hospitals in Egypt and Khobar Government Hospital in Saudi Arabia. Data covered delivery details, estimated blood loss, transfusion needs, intraoperative complications, and newborn outcomes.

The differences ran in the same direction, and the gap was not subtle. In the previa group, mothers were significantly older, had higher pre-pregnancy body mass index, and had been pregnant and given birth more often. An anterior placental position was far more common. At delivery, the previa cases lost markedly more blood.

• Gestational age at delivery was significantly lower in the previa group.
• Estimated blood loss was markedly higher.
• Red blood cell transfusions increased, along with higher rates of bladder injury and vascular injury.
• Newborns faced more preterm birth, more neonatal intensive care unit admissions, and lower one-minute Apgar scores.

An Apgar score is a ten-point check of a newborn’s breathing, heart rate, color, reflexes, and muscle tone at one and five minutes. A low one-minute score does not predict long-term problems by itself, but here it matched a pattern: babies born to previa mothers arrived earlier and in worse shape, which is what landed more of them in the neonatal intensive care unit.

Blood loss matters because PAS surgery can shed a patient’s entire blood volume in minutes. When the abnormal vessels are torn, the only control is a rapid hysterectomy and a massive transfusion. The finding that previa cases needed more red blood cell units is therefore not a minor difference; it is the difference between a managed operation and an emergency.

“Previa is the flag everyone knows to look for, and our data show why: these are the patients who bleed the fastest and deliver the earliest,” said Tarek El-Behiedy, the study’s lead author. “But the larger group without previa is where the next improvement has to happen, because their disease can be just as real before anyone has reason to suspect it.”

The hidden risk without previa

The 312 non-previa cases deserve attention, not reassurance. Earlier work by Carusi and colleagues at two United States referral centers, reported in Obstetrics & Gynecology, found that about 30% of hysterectomy-confirmed PAS cases had no previa at delivery, and those patients were far less likely to be diagnosed before surgery. A 2023 meta-analysis in the American Journal of Obstetrics and Gynecology MFM reached a similar conclusion: PAS without previa tends to be milder but is often missed antenatally, and its risk factors — assisted reproduction and prior uterine procedures — differ from the prior-cesarean pattern seen in previa cases.

In the Egyptian–Saudi cohort, the non-previa share is even higher, at 83%. That does not necessarily mean the disease behaves differently there. It may reflect how the two centers define and enroll cases, or that referral hospitals see a broader mix than studies restricted to hysterectomy specimens. Either way, screening built around previa would overlook the larger part of the problem in these settings.

The full paper, Clinical Outcomes of Placenta Accreta Spectrum with and without Placenta Previa: A Two-Center Comparative Study, is open via its DOI.

Why some experts are cautious

An independent maternal-fetal medicine specialist who was not part of the research added a cautionary note: “The comparison is useful, but the uneven group sizes mean the previa estimates carry wider uncertainty than the headline numbers suggest. An observational cohort also cannot fully separate the effect of previa itself from the effect of being older, heavier, and having carried more pregnancies — all of which clustered in that group.”

Those are not academic quibbles. The previa group numbered 63, a modest sample for rare complications such as bladder or vascular injury. Two centers with their own protocols also differ in blood bank readiness, surgical skill mix, and how referrals arrive. So the direction of the findings is convincing, while the exact size of each gap should be treated as an estimate rather than a fixed multiplier.

The published abstract does not list funding sources or conflicts of interest for the study. That absence may simply reflect the journal’s format, but it leaves the financing question unanswered.

What this means for care

For a clinician in a busy maternity unit, the takeaway is practical. Risk screening cannot stop at previa. A woman with prior cesarean deliveries, assisted reproduction, or repeated uterine procedures deserves PAS-level surveillance even when the placenta sits high in the uterus. When previa is present alongside an anterior placenta, teams should prepare for major hemorrhage, with blood products ready and a surgical plan that anticipates bladder and vascular injury.

The authors reach the same conclusion: early identification through systematic screening and multidisciplinary team management in specialized centers are what optimize outcomes for these pregnancies. That standard has been building across the field for a decade, and this two-center comparison adds Middle Eastern evidence to it.

The next five to ten years

If cesarean rates continue their climb, PAS will follow. The useful direction is earlier, previa-independent recognition, matched with surgical protocols that already keep improving. Risk-factor-based screening, standardized ultrasound markers, and regional referral pathways could shift more cases from emergency to planned delivery. For Egypt and Saudi Arabia, where this study’s numbers now add local weight, the coming decade will test whether multidisciplinary teams can reach the hospitals where most women actually deliver — not just the flagship centers.

Photo by Brett Jordan on Unsplash