Friday, December 23, 2016 Written by Dr. Najoua El Helali, Microbiologiste, Hôpital Paris-Saint-Joseph

Less Uncertainty — Better Safety — More Healthy Newborns

Paris-Saint-Joseph Hospital reduces GBS infection rate and improves patient management with Xpert® GBS and GeneXpert® System.

Dr. Najoua El Helali: A contemporary thought leader on the prevention of early onset neonatal infections. Based in Paris-Saint-Joseph Hospital she has been a member of the French health agency recommendations group for the prevention of early onset neonatal infections (2001–2002), and has been instrumental in the implementation of real-time PCR for intrapartum screening at the Point of Care in the maternity ward using Xpert GBS on the GeneXpert System.

Paris-Saint-Joseph Hospital is a consolidated private healthcare group of three hospitals: Saint-Joseph, Notre Dame de Bon Secours and Saint-Michel. The Paris-Saint-Joseph Hospital was certified in 2010 by the National Health Authority and its maternity unit has recognized as a reference for pathological pregnancies, childbirth, and postpartum disorders. The team at the hospital aims to improve the quality of life of the patient by investing in new technologies and advanced drugs.

In 2001 France introduced GBS vaginal screening for women at 35–37 weeks of pregnancy, with intrapartum antibiotic prophylaxis (IAP) being given to women who test antenatal positive. Women with unknown GBS status at the time of delivery received IAP if they presented risk factors (e.g., membrane rupture > 12 hours and/or fever > 38°C and/or delivery < 37 weeks).

At Paris-Saint-Joseph Hospital, these recommendations resulted in a reduction in the incidence of proven early onset GBS disease (EOGBSD) cases from 1.3 in the late 1990’s to 0.7 per 1000 live births by 2009. During the same period, the global incidence of proven and probable1 EOGBSD cases fell from 13.3 to 8.3 per 1000 live births. However, monitoring cases between April 2007 and December 2009 revealed that 65% of babies hospitalized for EOGBSD were born to mothers whose antenatal screening was negative.

A further study2 compared intrapartum with antenatal screening and showed that nearly half of the women who tested positive during labor were not detected by antenatal screening, and 42% who were positive at 35–37 weeks were actually intrapartum negative. The positive predictive value of antenatal screening for identifying colonization status at delivery was only 58.7%, whereas the negative predictive value was imperfect (92.1%), leading to inadequate prophylaxis for mothers and newborn babies still at risk for EOGBSD.

As a result, Paris-Saint-Joseph Hospital evaluated the performance and the feasibility of intrapartum testing with Xpert GBS. The test provided good performance comparable to culture methods (98.5% sensitivity, 99.6% specificity, 97.8% positive predictive value and 99.7% negative predictive value)2 , with actionable results made available in just 30–50 minutes. The test was simple and quick enough that it could be performed by midwives at the admission for delivery in order to target appropriate IAP to prevent EOGBSD.

In January 2010, intrapartum Xpert GBS screening was introduced for term deliveries in Paris-Saint-Joseph Hospital. During that first year, on-demand, intrapartum Xpert GBS screening was performed for 2,814 term deliveries. The GBS colonization rate increased from 11.7% in 2009 (previous antenatal screening rate) to 16.7% in 2010 and resulted in 436 women receiving appropriate IAP.

1 The Impact of the Intrapartum Xpert GBS screening3:

From 2009 to 2010, the number of EOGBSD cases was decreased by nearly half. There were 8 fewer probable cases and no proven cases.

There were no severe cases of EOGBSD using the intrapartum screening strategy in 2010.

Length of Hospital Stay (LOS) nearly halved the neonatal bed days and even more significantly ICU bed days dropped from 43 to 4.

Cost and effectiveness of the intrapartum Xpert GBS strategy was estimated using direct costs, including screening costs, hospital costs for deliveries of healthy newborns, and costs of treating GBS infected newborns3. The average total cost per delivery was €1,386 ≈ $1,754 with Xpert GBS intrapartum screening in 2010 compared to €1,390 ≈ $1,759 when using antenatal screening in 2009.

2 Conclusion

The intrapartum screening is a very effective strategy for appropriately targeting IAP and prevent ing EOGBSD in newborns. The Xpert GBS test provides a highley accurate result for identifying GBS carriers at the onset of labor. The simplicity of the test means that it can easily be introduced at point of care and performed by midwives. In one year, the incidence of probable EOGBSD cases was reduced by nearly half and no proven cases were recorded. The impact was shown in the reduction in costs of treating GBS infected neonates in Paris-Saint-Joseph Hospital, and so the strategy was cost-neutral.

As a result of this success, in March 2011, the testing was transferred to the delivery room. Since then midwives have perfomed the test 24/7, on-demand, at the time of admission for delivery.

3 Intrapartum PCR is performed successfully by midwives at the point of care, in the delivery room, 24/7

4 Intrapartum Xpert GBS screening continues to help save babies’ lives at risk of EOGBS disease at Paris-Saint-Joseph Hospital


1. Agence Nationale d’Accre´ditation et d’Evaluation en Sante´. Antenatal prevention of the risk of early neonatal bacterial infection. Clinical practice guidelines. September 2001:1–10.
2. Diagnostic Accuracy of a Rapid Real-Time Polymerase Chain Reaction Assay for Universal Intrapartum Group B Streptococcus Screening. El Helali et al., CID 2009:49, 417-423.
3. Cost and Effectiveness of Intrapartum Group B Streptococcus Polymerase Chain Reaction Screening for Term Deliveries. El Helali et al., Obstetrics and Gynecology 2012:119 N°4, 822-829.