[Occiput posterior presentation at delivery: Materno-foetal outcomes and predictive factors of rotation]. / Accouchement en variété occipito-postérieure : issues materno-fœtales et facteurs prédictifs de la rotation.

OBJECTIVES: To describe the maternal and foetal outcomes of an occiput posterior foetal position at delivery; to evaluate predictive factors of anterior rotation during labour. METHODS: Descriptive retrospective analysis of a cohort of 439 women with foetuses in occiput posterior position during labour. Logistic regression analysis to quantify the effect of factors that may favour anterior rotation. RESULTS: Most of foetuses (64%) do an anterior rotation during labour and 13% during the expulsive phase. The consequences of a persistent foetal occiput posterior position during delivery are a significantly increased average time of second stage labour compared to others positions (65.19minutes vs. 43.29, P=0.001, respectively); a higher percentage of caesarean sections (72.0% versus 4.7%, P<0.001) and instrumental delivery (among low-birth deliveries, 60.7% versus 25.2%, P<0.001); more frequent third-degree perineal tears (14.3% vs. 0.6%, P<0.001) and more abundant blood loss (560mL versus 344mL, P<0.001). In a multi-variable model including nulliparity, station of the presenting part and degree of flexion of the foetal head at complete dilatation, the only predictive factor independent of rotation at delivery is a good flexion of the foetal head at complete dilatation, which multiplies the anterior rotation probability by six. CONCLUSION: A good flexion of the foetal head is significantly associated with anterior rotation. Other studies exploring ways to increase anterior rotation during labour are needed to reduce the very high risk of caesarean section and instrumentation associated with the foetal occiput posterior position.

Fetal head position and perineal distension associated with the use of the BD Odon Device™ in operative vaginal birth: a simulation study.

OBJECTIVE: To investigate (1) the placement of the BD Odon Device on the model fetal head and (2) perineal distention during simulated operative vaginal births conducted with the BD Odon Device. DESIGN: Observational simulation study. SETTING: North Bristol NHS Trust, UK. POPULATION OR SAMPLE: Four hundred and forty simulated operative vaginal births. METHODS: Three bespoke fetal mannequins were developed to represent (1) bi-parietal diameter of the 50th centile at term, (2) bi-parietal diameter at the 5th centile at term, and (3) 50th centile head with 2 cm of caput. Siting of the BD Odon Device on model heads was determined before and after 400 simulated operative vaginal births. Variables were analysed to determine their effect on device siting and movement during birth. The fetal mannequins were placed inside a maternal mannequin and the BD Odon Device was placed around the fetal head as per the instructions for use. The location of the air cuff was determined before and after the head was delivered. Perineal distension was determined by recording maximum perineal distention during a simulated operative vaginal birth using the same procedure, as well as scenarios employing an inappropriately non-deflated air cuff (for the BD Odon Device), the Kiwi ventouse and non-rotational forceps. MAIN OUTCOME MEASURES: Site and displacement during birth of the BD Odon Device on a model head. Maximal perineal distension during birth. RESULTS: The BD Odon Device was reliably sited in a standard over the fetal head position (approximately 40 mm above the fetal chin) for all stations, head sizes and positions with no significant displacement. In occipito-posterior births, compared with occipito-anterior or transverse, the BD Odon Device routinely sited further down the fetal head (toward the chin). The BD Odon Device was not associated with more perineal distension compared with forceps or Kiwi ventouse (respectively 21, 26 and 21 mm at posterior fourchette). CONCLUSIONS: The BD Odon Device reliably sited over a safe area of the fetal head in 400 simulated births representative of clinical practice. The BD Odon Device generates similar levels of perineal distension compared with Kiwi ventouse when used correctly. TWEETABLE ABSTRACT: Location of the BD Odon Device on a fetal head in simulation.

Pressure and traction on a model fetal head and neck associated with the use of forceps, Kiwi™ ventouse and the BD Odon Device™ in operative vaginal birth: a simulation study.

OBJECTIVE: To determine the pressure and traction forces exerted on a model fetal head by the BD Odon Device, forceps and Kiwi ventouse during simulated births. DESIGN: Simulation study. SETTING: Simulated operative vaginal birth. POPULATION OR SAMPLE: Eighty-four simulated operative vaginal births. METHODS: A bespoke fetal mannequin with pressure sensors around the head and strain gauge across the neck was used to investigate pressure applied over the head, and traction across the neck during 84 simulated births using the BD Odon Device, non-rotational forceps and Kiwi ventouse. MAIN OUTCOME MEASURES: Peak pressure on the fetal face and lateral aspects of the head during correct use of the BD Odon Device and forceps. Peak pressure on orbits and neck during misplacement of the BD Odon Device and forceps. Peak traction force generated until instrument failure using the BD Odon Device, forceps and Kiwi ventouse. RESULTS: When correctly sited and using 80 kPa inflation pressure on the cuff, the BD Odon Device generated a lower peak pressure on the fetal head than forceps (83 versus 146 kPa). When instruments were purposefully misplaced over the orbits, the BD Odon Device generated a lower peak pressure on the orbits compared with forceps (70 versus 123 kPa). When purposefully misplaced over the neck, the BD Odon Device, compared with forceps, generated a greater peak pressure on the anterio-lateral aspect of the neck (56 versus 17 kPa) and a lower peak pressure on the posterior aspect of the neck (76 versus 93 kPa) than forceps. In cases of true cephalic disproportion, the BD Odon Device 'popped-off' at a lower traction force than did forceps (208 versus 270 N). CONCLUSIONS: In simulated assisted vaginal birth with correctly placed instruments, the peak pressure exerted on the fetal head by a BD Odon Device is lower than the pressure exerted by non-rotational forceps. In cases in which delivery of the fetal head is not possible due to cephalo-pelvic disproportion, lower traction forces could be applied using the BD Odon Device than with forceps before the procedure was abandoned due to device failure. TWEETABLE ABSTRACT: BD Odon Device exerts less pressure on a model fetal head than forceps, but more than Kiwi ventouse.

Fasting glycaemia to simplify screening for gestational diabetes.

OBJECTIVE: Recommendations in Switzerland on screening for gestational diabetes endorse the International Association of Diabetes in Pregnancy Study Group consensus. As universal testing is time consuming and glucose loading is unpleasant, the recommendations include a simplification, not performing the glucose loading in women with fasting glycaemia <4.4 mmol/l. Our objective was to evaluate the diagnostic performance of this simplified strategy, compared with the complete test, in our population with a low prevalence of gestational diabetes. DESIGN: We collected 2298 complete 75-g glucose tolerance tests. We simulated stopping the test, so avoiding the glucose loading and further glycaemia, if fasting glycaemia was <4.4 or ≥5.1 mmol/l. SETTING AND POPULATION: Unselected pregnant women from Geneva and Basel, at 24-28 weeks of gestation. METHODS: We calculated the sensitivity, and the percentage of women who would avoid the complete test with the strategy based on fasting glycaemia. RESULTS: The prevalence of gestational diabetes was 10.9% in our population. Among 251 women with gestational diabetes, fasting glycaemia was ≥5.1 mmol/l in 119 women (47.4%), between 4.4 and <5.1 mmol/l in 78 women (31.1%) and <4.4 mmol/l in 54 women (21.5%). Proceeding with the complete test only in women with fasting glycaemia between 4.4 and <5.1 mmol/l will result in a sensitivity of 78.5%. This strategy would avoid glucose loading in 63.8% of women. CONCLUSIONS: Screening with fasting glycaemia is an attractive alternative to universal screening with the complete 75-g glucose tolerance test. This strategy is, however, slightly less sensitive than previously reported in higher-risk populations. TWEETABLE ABSTRACT: Fasting glycaemia can be considered as an alternative to the complete test for gestational diabetes screening.

Maternal positioning to correct occiput posterior fetal position during the first stage of labour: a randomised controlled trial.

OBJECTIVE: To evaluate the efficacy of the hands and knees position during the first stage of labour to facilitate the rotation of the fetal head to the occiput anterior position. DESIGN: Randomised controlled trial. SETTING: Geneva University Hospitals, Switzerland. POPULATION: A total of 439 women with a fetus in the occiput posterior position during the first stage of labour. METHODS: The women in the intervention group were invited to take a hands and knees position for at least for 10 minutes. Women allocated to the control group received the usual care. For both groups, 15 minutes after randomisation, women completed a short questionnaire to report their perceived pain and the comfort of their position. MAIN OUTCOME MEASURES: The rotation of the fetal head in occiput anterior position confirmed by ultrasonography 1 hour after randomisation. RESULTS: One hour after the randomisation, 35 of 203 (17%) fetuses were diagnosed as being in the occiput anterior position in the intervention group compared with 24 of 209 (12%) in the control group. This difference was not statistically significant (relative risk 1.50; 95% CI 0.93-2.43; P = 0.13). The change in the evaluation of comfort between the randomisation and 15 minutes after showed an improvement in 70 and 39 women, no change in 82 and 78 women and a decrease in 56 and 86 women in the intervention and control groups, respectively (P = 0.02). CONCLUSIONS: This study could not demonstrate a benefit of the hands and knees position to correct the occiput posterior position of the fetus during the first stage of labour, but the women reported an increase in their comfort level. TWEETABLE ABSTRACT: Hands and knees position does not facilitate rotation into occiput anterior but increases the comfort level of women.

Elective induction of labour and maternal request: a national population-based study.

OBJECTIVE: To estimate the rate of elective inductions in France and the proportion of them that were maternally requested, and to study the factors associated with elective inductions that were or were not requested by women. DESIGN: Cross-sectional population-based study. SETTING: All maternity units in France. POPULATION: About 14 681 women from the 2010 French National Perinatal Survey of a representative sample of births. METHODS: Inductions were classified as elective based on their indications and maternal and fetal characteristics, collected from medical records. Elective inductions requested by women were identified from the mother's postpartum interviews. Polytomous logistic regression analysis was used to study the determinants of inductions that were or were not maternally requested. Women with spontaneous labour served as the comparison group. MAIN OUTCOME MEASURE: Rate of elective inductions. RESULTS: The induction rate was 22.6, 13.9% elective. Among elective inductions, 47.3% were requested by women. The characteristics of mothers, pregnancies, and maternity units were similar in both groups of elective inductions. The main associated factors were parity 2 or more [adjusted odds ratio (OR) 4.7, 95% confidence interval (CI) 3.1-7.2 for maternally requested inductions and aOR of 1.8 (95% CI1.2-2.7) for unrequested inductions, compared with parity 0] and private hospital status [aOR 4.5 95% (CI 3.3-6.0) for maternally requested inductions and aOR 3.7 (95% CI 2.8-4.9) for inductions not requested by the mother]. We found no association between maternal social characteristics and type of elective induction. CONCLUSION: Parity and organisational factors appear to influence the decision about elective inductions. It would be interesting to determine how obstetricians and women make this decision and for what reasons. TWEETABLE ABSTRACT: About 13.9% of inductions of labour were elective in France, 47.3% of these requested by women.

[Induction of labour: benefits and risks]. / Déclenchement de l'accouchement: le pour et le contre.

A large proportion of pregnant women have induction of labour at or near term. Few randomized trials have evaluated the various indications to induce labour. In some cases, induction is highly recommended to avoid a life-threatening complication for the fetus or the mother. In other cases, the indication is controversial. We review the evidence for a benefit in case of post-term, premature rupture of membranes, maternal hypertensive disorders and suspicion of fetal macrosomia. In case of maternal diabetes or intrauterine growth impairment the need for induction of labour must probably be discussed according to the clinical features. In the above mentioned indications, it does not seem that the risk of caesarean section is increased.

[Atypical presentation of preeclampsia]. / Les présentations cliniques atypiques de la prééclampsie.

Preeclampsia is a pregnancy-related syndrome, which still represents one of the major causes of maternal-fetal mortality and morbidity. Diagnosis can be made difficult due to the complexity of the disorder and its wide spectrum of clinical manifestations. In order to provide an efficient diagnostic tool to the clinician, medical societies regularly rethink the definition criteria. However, there are still clinical presentations of preeclampsia that escape the frame of the definition. The present review will address atypical forms of preeclampsia, such as preeclampsia without proteinuria, normotensive preeclampsia, preeclampsia before 20 weeks of gestation and post-partum preeclampsia.

Prevention of preterm delivery with vaginal progesterone in women with preterm labour (4P): randomised double-blind placebo-controlled trial.

OBJECTIVE: To evaluate the effectiveness of 200 mg of daily vaginal natural progesterone to prevent preterm birth in women with preterm labour. DESIGN: Multicentre, randomised, double-blind, placebo-controlled trial. SETTING: Twenty-nine centres in Switzerland and Argentina. POPULATION: A total of 385 women with preterm labour (24(0/7) to 33(6/7) weeks of gestation) treated with acute tocolysis. METHODS: Participants were randomly allocated to either 200 mg daily of self-administered vaginal progesterone or placebo within 48 hours of starting acute tocolysis. MAIN OUTCOME MEASURES: Primary outcome was delivery before 37 weeks of gestation. Secondary outcomes were delivery before 32 and 34 weeks, adverse effects, duration of tocolysis, re-admissions for preterm labour, length of hospital stay, and neonatal morbidity and mortality. The study was ended prematurely based on results of the intermediate analysis. RESULTS: Preterm birth occurred in 42.5% of women in the progesterone group versus 35.5% in the placebo group (relative risk [RR] 1.2; 95% confidence interval [95% CI] 0.93-1.5). Delivery at <32 and <34 weeks did not differ between the two groups (12.9 versus 9.7%; [RR 1.3; 95% CI 0.7-2.5] and 19.7 versus 12.9% [RR 1.5; 95% CI 0.9-2.4], respectively). The duration of tocolysis, hospitalisation, and recurrence of preterm labour were comparable between groups. Neonatal morbidity occurred in 44 (22.8%) cases on progesterone versus 35 (18.8%) cases on placebo (RR: 1.2; 95% CI 0.82-1.8), whereas there were 4 (2%) neonatal deaths in each study group. CONCLUSION: There is no evidence that the daily administration of 200 mg vaginal progesterone decreases preterm birth or improves neonatal outcome in women with preterm labour.

[External cephalic version in case of persisting breech presentation at term: motivations and women's experience of the intervention]. / Version céphalique externe en cas de siège persistant à terme : motivations et vécu de l'intervention par les femmes.

OBJECTIVES: To evaluate the efficacy and acceptability of external cephalic version (ECV). MATERIALS AND METHOD: From 2004 to 2008, 212 pregnant women between 34-37 weeks of gestation with fetus in breech presentation were included in a randomized clinical trial and 125 externals cephalic versions were studied. RESULTS: A success rate of 37.6%t was recorded. At 34 weeks of gestation, 80.6% of women were considering an ECV in the event of persistent breech position at 37 weeks. These women expressed the desire to give birth vaginally (52% versus 24.4%, P<0.001). In contrast, others women preferred an elective cesarean section to avoid the risk of a breech vaginal delivery. Women felt pain during the ECV and scored 60 on average using the analogical visual scale. Women rated on a verbal rating scale the ECV as severely painful to unbearable (68%), and as stressful (70%). Despite this, the majority of women would recommend ECV to their friends or would be willing to repeat it for themselves. DISCUSSION AND CONCLUSION: ECV remains a scary and painful medical procedure. More research is needed to reduce the impact. The use of analgesic medication for this indication is controversial. Hypnosis could be an alternative to evaluate.

[What's new in gynecology and obstetrics]. / Gynécotogie et obstétrique.

Because of the lack of screening methods, ovarian cancer remains one of the major causes of mortality in gynecological oncology. Prevention by salpingectomy, based on a concept about the origin of serous carcinoma, may be proven effective in the future. Regarding cervical cancer, screening methods are improving and the benefit of HPV-HR testing has been recently demonstrated. Metabolic requirements and exercise are modified during pregnancy. Present recommendations are for pregnant women to practice regular moderate exercise, as in a non-pregnant population. This guideline, despite being reasonable, is not based on strong evidence. A randomised trial is ongoing in our Department to evaluate the effects of exercise in women with gestational diabetes.

OS014. Which first-line drug to control severe hypertension in pregnancy? A pilot study.

INTRODUCTION: Severe hypertension is a common complication in pregnancy-associated hypertensive disorders and there is no clear consensus on which first-line antihypertensive drug to use in this setting. OBJECTIVES: To determine the efficacy and safety of four antihypertensive drugs (two intravenous and two oral) in pregnant women with severe hypertension. METHODS: Pilot prospective randomised study. INCLUSION CRITERIA: pregnant women with a gestational age >24weeks and admitted in the Obstetrics Department with severe hypertension defined as systolic blood pressure (SBP) ⩾165mmHg and/or diastolic blood pressure (DBP) ⩾105mmHg. The women were randomised in 4 groups to receive:-20mg intravenous labetalol;-5mg intravenous hydralazine;-10mg oral nifedipine tablets ;-10mg sublingual nifedipine. Treatment was repeated every 20mn until target SBP and DBP were reached (⩽150/⩽95mmHg). The primary endpoint was the time needed to achieve effective blood pressure control. Treatment failure was defined as the unability to reach the target BP within one hour. RESULTS: After giving informed consent, 41 pregnant women admitted with severe hypertension were randomised. Mean age was 35 years (SD 3.5), 65% were nulliparous and mean SBP and DBP at admission were 176 (SD 16) and 105 (SD 12)mmHg, respectively. Success to achieve target BP was reached in all patients within the oral 10mg nifedipine group (11 patients), in all but one patients with the 10mg sublingual group (12 patients), and only in 5 out of 9 patients and 6 out of 9 patients within the labetalol and hydralazine groups. They were only one hypotension (defined as SBP <120mmHg) in the two groups with intravenous drugs and 3 and 5 in the oral and sublingual nifedipine groups. CONCLUSION: These results indicate that oral nifedipine seems more effective than intravenous labetalol or hydralazine to reach BP control in pregnant patients with severe hypertension. A large scale randomized trial comparing oral nifedipine versus these commonly used intravenous antihypertensive drugs should be implemented in order to determine whether oral nifedipine is a more effective treatment in this population.

OS108. Preeclamptic women display salt sensitivity and cardiovascular damage before their menopause.

INTRODUCTION: Salt sensitivity is an important cardiovascular risk factor. It has been shown that preeclamptic (PEC) women may not be totally cured after the delivery and keep a higher cardiovascular risk than nonPEC women. OBJECTIVES: We aimed to study the salt sensitivity of the blood pressure in women with a history of severe preeclamspia and women with no history of hypertensive complications.The design was a case control study with intervention, including 42 women recruited 5 to 17 years following delivery. METHODS: 21 women having suffered from a severe preeclampsia before 34 weeks of pregnancy and 19 age, race matched controls women,were randomized to follow for one week a low salt (LS) diet and a high salt (HS) diet (adding 6g NACL/d to usual diet). On day seven of each dietary period, 24h ambulatory blood pressure was recorded, and 24h urine collected in order to measure sodium excretion.Salt sensitivity was assigned if the mean 24h blood pressure increased by ⩾ 3mmHg on a high- compared with a low-salt diet. RESULTS: Preeclamptic women were aged 39.1(24-49) and controls 40.1(29-49), p=NS.Two of the PEC women already suffered from a cardiovascular event (2coronary events). The PEC women showed a significant increase of the BP and standard deviation (SD) of the BP compared to the controls.10 (47.6%) preeclamptic women showed salt sensitivity (odd ratio 5.4, 95% CI 0.972-30.601;P=0.042).Recurrent preeclampsia was associated with a significantly high risk to salt sensitivity status (OR 5; 95% confidence interval 1.1-31.6). CONCLUSION: Severe PEC women display already salt sensitivity of the blood pressure before their menopause and increased variability of the BP. Recurrent preeclampsia is a high risk factor for salt sensitivity and could allow to target this high-risk group at an early stage for preventive measures for cardiovascular disease.

PP108. Post-partum evaluation of the blood pressure and the kidney function in pre-eclamptic women.

INTRODUCTION: Recent data have shown that preeclampsia is not just a disease of pregnancy that resolves with delivery. Preeclampsia may be considered a 'risk marker' for later-life diseases, including cardiovascular and renal diseases and the metabolic syndrome. OBJECTIVES: We aimed a longitudinal prospective study to analyze the renal abnormalities in the post-partum. METHODS: We studied 127 post-preeclamptic women at 6 weeks post-partum. Twenty-four hour urine collection, ambulatory blood pressure and renal function were evaluated. RESULTS: The mean age (±SD) was 32±6years, BMI was 29.4±5.7, the race distribution was Caucasian 69%, Hispanic 14%, Black 12% and Orient 5%. Ten % were active smokers, 10% have been suffering from gestational diabetes. The mean duration of the pregnancy was 36 weeks 3/7±4. Our results show that the prevalence of hypertension defined by office blood pressure ⩾140/90 mmHg or ongoing antihypertensive treatment was 35%. The daytime ambulatory blood pressure (ABPM) was 122±16/85±11 mmHg, heart rate 84±8, and 111±20/75±11 mmHg at nighttime.Sixteen % had a daytime ABPM ⩾135/85mmHg corresponding to the definition of ambulatory hypertension. Ultrasensitive CRP was 4.9±5.1mg/ml, of them 31% had a frank elevation of the CRP >4. The glomerular filtration rate evaluated by the Gault-Cockroft equation showed a hyperfiltration with a mean value of 150±42ml/min. Eleven% had a decreased GFR < 90 ml/min. Microalbumine/creatinine ratio measured in the urine spot was 7 ±4. Mean microalbuminuria was 225±529mg/d measured on the 24h urine collection.Urine 24h Na excretion rate was 204±48 mmol/d. CONCLUSION: In conclusion, after the post-partum period, women having suffered from a pre-eclampsia display many cardiovascular risk factors with a high prevalence of hypertension, microalbuminuria, renal hyperfiltration and elevated CRP. These women should be carefully screened, and sub-groups with the higher risk have to be targeted for prevention and treatment, and close follow-up.

[Psychosocial risk factors and preterm delivery]. / Facteurs de risque psychosociaux et accouchement avant terme.

Delivery before term (at less than 37 weeks of gestation) represents 5 to 10% of the deliveries and is an important cause of perinatal mortality and morbidity. Few improvements in prevention have been made. Difficulties include the multiplicity of medical risk factors, the absence of reliable diagnostic tests and the limited effectiveness of medical treatment. Several studies have shown that psychosocial risk factors are associated with preterm labour. The identification and management of these risk factors and of unfavorable social environment may potentially reduce the risk of preterm delivery. We describe and discuss the studies evaluating psychosocial interventions aiming at reducing the risk of prematurity.

[Management of gestational diabetes: current knowledge and future perspectives]. / Prise en charge du diabète gestationnel: nouvelles connaissances et perspectives futures.

Gestational diabetes (GDM) is one of the most common complications of pregnancy and its prevalence is increasing continuously. Diagnosis, screening of GDM and therapeutic interventions are topics of ongoing controversies and uncertainty that have contributed to make the management of GDM complex and different from one country to another. Recent studies, such as ACHOIS and HAPO, have contributed to better define screening criteria and international recommendations and have demonstrated that management of GDM, including glucose monitoring, diet and insulin if needed, is worthwhile. This article summarizes the current status of screening, management of GDM and postpartum follow-up.

Maternal heart rate changes during labour.

OBJECTIVES: Labour and delivery represent a considerable effort for pregnant women. Lack of aerobic fitness may limit pushing efforts during childbirth and represents increased cardiovascular strain and risk. Increasing prevalence of sedentary behaviour and lack of aerobic fitness may reduce heart rate reserve during labour. STUDY DESIGN: We quantified maternal heart rate reserve (maximum heart rate minus resting heart rate) of 30 healthy pregnant women during labour and delivery and related it to habitual daily physical activity levels quantified during the third pregnancy trimester by the Pregnancy Physical Activity Questionnaire. RESULTS: Heart rates during labour reached values similar to those observed during moderate to heavy physical exercise. During active pushing one out of five women reached heart rates more than 90% of their heart rate reserve (188 ± 7 beats per min). Half of the women reached more than 70% of heart rate reserve (172 ± 14 beats per min). Physically inactive women used more of their heart rate reserve as physically more active women (87 ± 20% vs. 65 ± 12%, upper and lower tertile respectively, p<0.05). CONCLUSIONS: Use of heart rate reserve for the effort of labour is increased in physically inactive women and may potentially limit the intensity and duration of pushing efforts. Such higher cardiovascular strain in physically less active women may represent increased cardiovascular risk during labour.

Intrapartum Group B streptococcus detection by rapid polymerase chain reaction assay for the prevention of neonatal sepsis.

Group B streptococcus (GBS) is a leading cause of infectious neonatal morbidity and mortality. Timely and accurate identification of colonized mothers is imperative so that antibioprophylaxis can be implemented during labour to reduce the risk of neonatal sepsis. We planned our study to analyse the diagnostic accuracy of an intrapartum PCR assay to identify GBS-colonized women and to allow the implementation of correct (i.e. at least 4 h) intrapartum antibiotic prophylaxis based on the PCR results. We included 695 women in labour who were tested for rectovaginal GBS carriage by culture and PCR. Women were also screened at 35-37 weeks of gestation. Intrapartum GBS colonization was 19.3%. Assay sensitivity was 81.0% for antenatal culture and 85.0% for intrapartum PCR; p 0.72. GBS colonization (n = 107) was known at least 4 h before delivery in 68 (64%) and 73 (68%) women based on antenatal culture and intrapartum PCR, respectively. Among 43 women delivering preterm, correct status was known at least 4 h before delivery in 10 (23%) and 32 (74%) women according to antenatal culture and intrapartum PCR, respectively. These results support the concept that GBS screening can be performed routinely during labour in a clinical setting. The intrapartum approach is at least as accurate as the antenatal screening, with the additional advantage of identifying women delivering preterm or not followed during pregnancy.