Niels Uldbjerg

Aarhus University | AU · Department of Obstetrics and Gynaecology

Purpose Conventional vaginal strain ultrasound elastography, not based on shear-wave elastography imaging, can assess the biomechanical properties of the uterine cervix. This assessment may inform the risks of preterm birth and failed induction of labor. However, there is considerable variation in the approaches to strain elastography, including th...

Introduction Managing obstetric shoulder dystocia requires swift action using correct maneuvers. However, knowledge of obstetric teams' performance during management of real‐life shoulder dystocia is limited, and the impact of non‐technical skills has not been adequately evaluated. We aimed to analyze videos of teams managing real‐life shoulder dys...

Objective To compare ultrasound‐assessed fetal head circumference (HC), abdominal circumference (AC), HC/AC ratio, and estimated fetal weight (EFW) in prediction of large‐for‐gestational‐age (LGA) at birth in pregnancies affected by type 1 (T1DM) and type 2 (T2DM) diabetes. Methods This retrospective cohort study included all women with T1DM and T...

( BJOG . 2023;130(9):1087–1095) Major postpartum hemorrhage (PPH) is classified as losing more than or equal to 1 L of blood within 2 hours of vaginal birth. In Denmark, this occurs in 7.2% of vaginal deliveries, compared with an incidence of about 4% in the developed countries. Managing major PPH requires a quick and appropriate response from mult...

Background Current guidelines regarding oxytocin stimulation are not tailored to individuals as they are based on randomised controlled trials. The objective of the study was to develop an artificial intelligence (AI) model for individual prediction of the risk of caesarean delivery (CD) in women with a cervical dilatation of 6 cm after oxytocin st...

Introduction Vacuum extraction is generally considered an operator-dependent task, with most attention directed toward the obstetrician’s technical abilities (1–3). Little is known about the effect of the team and non-technical skills on clinical outcomes in vacuum-assisted delivery. This study aimed to investigate whether the non-technical skills...

INTRODUCTION Early discharge holds several advantages and seems safe after planned cesarean section among low-risk women. However, breastfeeding rates are lower after cesarean section. Thus, concern has been raised that early discharge among these women may affect breastfeeding even further. Therefore, we aimed to assess the effect of early dischar...

Clinically, unique markers in fetal membrane cells may contribute to the search for biomarkers for preterm prelabor rupture of the fetal membranes (pPROM) in maternal blood. pPROM is associated with overwhelming inflammation and premature cellular senescence causing “biological microfractures” of the fetal membranes. We hypothesize that these patho...

Objectives: To assess if a 10 min session of maternal hyperoxygenation increases cerebral tissue oxygenation as measured by magnetic resonance imaging (MRI) T2* in fetuses with and without congenital heart defects (CHDs). Study design: At mean gestational ages of 32 (early) and 37 (late), we measured fetal cerebral T2* before and during the last mi...

Objectives: We aimed to compare cell-based NIPT (cbNIPT) to chorionic villus sampling (CVS), and to examine the test characteristics of cbNIPT in the first clinical validation study of cbNIPT compared to cell-free NIPT (cfNIPT). Material and methods: Study 1: Women (N=92) who accepted CVS were recruited for cbNIPT (53 normal and 39 abnormal). Sa...

Objective During pregnancy, the stiffness of the cervical tissue decreases long before the cervical length decreases. Therefore, several approaches have been proposed in order to ensure a more objective assessment of cervical stiffness than that achieved by digital evaluation. Strain elastography has shown promising results. This technique is based...

Introduction The aim of the study was to compare two different techniques for closure of the caesarean uterotomy on the occurrence of a caesarean scar niche. Methods The study was a randomized controlled trial performed in a tertiary hospital with inclusion of singleton pregnant women with a scheduled, first caesarean section. We randomized partic...

The purpose of this publication is to describe the success, which you find at Obstetrics and Gynecology - online textbook for medical students - sundhed.dk, an easily accessible, up to date Obstetrics and Gynecology teaching for medical students including international students in the Nordic countries. In 2018, NFOG (the Nordic Federation of Societ...

Objective: To examine women and their partners' experience of major postpartum haemorrhage (PPH). Design: A qualitative interview study. Setting: Two Labour and Delivery Units in Denmark. Population: Women who experienced major PPH (≥ 1 litre within 2 hours after vaginal birth). Methods: Semi-structured interviews were conducted with 15 wo...

Objectives Video-assisted debriefing (VAD) of real-life obstetrical emergencies provides an opportunity to improve quality of care, but is rarely used in clinical practice. A barrier for implementation is the expected mental reservations among healthcare providers. The aim of this study was to explore healthcare providers’ perceptions and expectati...

Background: It is a matter of debate whether one universal standard such as Intergrowth-21st (IG-21) can be applied to all populations. Objective: We therefore aimed to establish a Danish Newborn Standard by the principles of the IG-21 Standard in order to compare the centiles of these two standards. A secondary objective was to compare the prev...

Introduction: Identifying hydatidiform moles (HMs) is crucial due to the risk of gestational trophoblastic neoplasia. When a HM is suspected on clinical findings, surgical termination is recommended. However, in a substantial fraction of the cases, the conceptus is actually a non-molar miscarriage. If distinction between molar and non-molar gestat...

Objective: To examine the factors associated with unexpectedly high rates of conversion to open label oxytocin in the CONDISOX trial of continuation vs discontinuation of oxytocin infusion during induced labour. Design: Secondary retrospective analysis of data from a prospective randomised controlled trial. Setting: Nine hospitals in Denmark a...

The aim was to assess the association between fetal growth restriction (FGR) and fetal heart rate variability (FHRV) in relation to fetal movements. A prospective observational cohort study was performed. Non‐invasive fetal electrocardiography (NI‐FECG) allowed beat‐to‐beat assessments with <5% corrections of RR intervals. FHRV analyses included: R...

Objective To examine the effect of including maternal age and body mass index (BMI; calculated as weight in kilograms divided by the square of height in meters) as additional risk factors in the traditional risk‐based strategy at term pregnancies consisting of previous early‐onset group B streptococcus (GBS) disease, GBS bacteriuria during pregnanc...

Objective to assess the effectiveness of the Child-Mother Index (CMI) as a risk factor for selected adverse maternal birth outcomes. Study design We assessed the CMI by multinomial regression models in register-based data, containing all singleton births in Denmark in 2009 with a gestational age between 37⁺⁰ and 41⁺⁶ weeks. CMI defined as the weig...

( Acta Obstet Gynecol Scand . 2021;100:955–963) Enhanced recovery (ERAC) programs aim to decrease the length of hospital stay (LOS) for patients who underwent cesarean delivery (CD). While it can be positive for some parents to be discharged early, it is unclear whether others find it difficult in regard to their sense of security. The aim of this...

Fetal heart rate variability (FHRV) reflects autonomic cardiac regulation. The au-tonomic nervous system constantly adjusts the heart rate to maintain homeosta-sis. By providing insight into the fetal autonomic state, FHRV has the potential to become an investigational and clinical instrument. However, the method needs standardization and the influ...

Objectives Fetal heart rate variability (FHRV) has shown potential in fetal surveillance. Therefore, we aimed to evaluate the reliability of time domain and spectral domain parameters based on non-invasive fetal electrocardiography (NI-FECG). Method NI-FECG, with a sampling frequency of 1 kHz, was obtained in 75 healthy, singleton pregnant women b...

( BMJ . 2021;372:n716) Oxytocin is commonly used to stimulate the uterus and induce labor. Hyperstimulation carries risks to mother and fetus and may increase the likelihood of cesarean delivery (CD). Recent studies suggest that discontinuing oxytocin augmentation will not interrupt labor but may help avoid hyperstimulation. It is unclear if discon...

Introduction Emerging evidence shows that women with endometriosis face a higher risk of preterm birth. However, the pathways are unclear. The objective of this study is to further investigate at different gestational ages the association between endometriosis and different pathways of preterm birth including, medically indicated preterm birth, pre...

Background Little is known about the importance of non-technical skills for the adherence to guidelines, when teams of midwives, obstetricians, anesthesiologists, and pediatricians resuscitate and support the transition of newborns. Non-technical skills are competences underpinning successful teamwork in healthcare. These are usually referred to as...

Introduction Two approaches have been suggested for cell-based non-invasive prenatal testing (cbNIPT); A) enrichment of extravillous trophoblasts (EVTs) from maternal blood using antibodies targeting a combination of mesodermal and ectodermal markers and B) enrichment of EVTs from cervical swabs using antibodies targeting human leukocyte antigen G....

Background The antenatal identification of placental dysfunction in small-for-gestational-age (SGA) fetuses with normal fetal Doppler flows remains an obstetric challenge. In a significant fraction of these pregnancies placental dysfunction is revealed by clinical manifestations such as preeclampsia, preterm delivery, or severe SGA at birth or by a...

Introduction In this feasibility study, we hypothesize that the evaluation of cervical biomechanical strength can be improved if cervical length measurement is supplemented with quantitative elastography, which is a technique based on conventional ultrasound elastography combined with a force‐measuring device. Our aims were to: (a) develop a force‐...

Early discharge after caesarean section requires that major surgical complications are diagnosed before the patient leaves the hospital. The aim of this retrospective observational study was therefore to assess the time interval from surgery to diagnosis of major complications in low-risk women after planned caesarean section, where early discharge...

Plasmacytoid dendritic cells (pDCs) constitute a rare type of immune cell with multifaceted functions, but their potential use as a cell-based immunotherapy is challenged by the scarce cell numbers that can be extracted from blood. Here, we systematically investigate culture parameters for generating pDCs from hematopoietic stem and progenitor cell...

(Abstracted from BMJ 2021;372:n716) Oxytocin stimulation is often used to induce labor. According to 4 meta-analyses, discontinuing oxytocin stimulation once active labor has begun may have some benefits, including reducing the rate of cesarean delivery.

Purpose Proof of concept of the use of cell-based non-invasive prenatal testing (cbNIPT) as an alternative to chorionic villus sampling (CVS) following preimplantation genetic testing for monogenic disorders (PGT-M). Method PGT-M was performed by combined testing of short tandem repeat (STR) markers and direct mutation detection, followed by trans...

Objective: Studies restricted to live births may underestimate severe teratogenic effects. We address the limitation by including data from both prenatal and postnatal diagnoses of cardiac malformations. Design: Register-based study. Setting: Denmark. Population: 364,012 singleton pregnancies from 2007 to 2014. Methods: We used data from f...

Objective To explore factors associated with a high vaginal GBS load during labor considering (1) the recto-vaginal GBS load at 35–37 weeks’ gestation determined by culture and (2) the vaginal GBS colonization determined by a polymerase chain reaction (PCR) assay during labor. Methods From an unselected cohort of 902 pregnant women, we obtained (1...

Objective To determine whether discontinuing oxytocin stimulation in the active phase of induced labour is associated with lower caesarean section rates. Design International multicentre, double blind, randomised controlled trial. Setting Nine hospitals in Denmark and one in the Netherlands between 8 April 2016 and 30 June 2020. Participants 120...

Objective: To compare mosaicisms in prenatal chorionic villus samples with corresponding postpartum placental samples. Method: We collected placentas from 15 consecutive cases of mosaicism detected in chorionic villus samples and obtained five standardized samples on each placenta after delivery. All pre- and postnatal placental samples were unc...

Background: This systematic review and meta-analysis summarizes the evidence for the association between endometriosis and adverse pregnancy outcome, including gestational hypertension, pre-eclampsia, low birth weight, and small for gestational age, preterm birth, placenta previa, placental abruption, cesarean section, stillbirth, postpartum hemor...

Introduction: Healthy women of reproductive age have a vaginal pH around 4.5, whereas little is known about pH in the upper genital tract. A shift in the vaginal microbiota may result in an elevated pH in the upper genital tract. This might contribute to decreased fertility and increased risk of preterm birth. Therefore, we aimed to measure pH in...

Introduction: In pregnancy, vitamin D deficiency is associated with increased risk of fetal growth restriction and preeclampsia. The underlying mechanisms are not known but placental dysfunction is believed to play a role in fetal growth restriction and preeclampsia. In a Danish population, where health authorities recommend a 10µg/day vitamin D s...

Objective: Attention-deficit/hyperactivity disorder (ADHD) medications are increasingly used in pregnancy. Studies on the pregnancy safety of these medications that are restricted to live births may underestimate severe teratogenic effects that cause fetal demise or termination of pregnancy. The present study addresses this limitation by including...

Introduction: In some European countries, discharge the day after planned cesarean section has become an accepted procedure. However, little is known about the patients' perception of early discharge. The aim of this study was to compare early discharge to standard care in relation to parental sense of security. Further, we evaluated postoperative...

Background In gestational trophoblastic disease, the prognosis is related to the genetic constitution. In some cases, taking a biopsy is contraindicated. Methods In a pregnant woman, ultrasound scanning suggested hydatidiform mole. To explore if the genetic constitution can be established without taking a biopsy (or terminating the pregnancy), cel...

Objective: We aimed to develop cell-based NIPT for cystic fibrosis (CF) and test a pregnancy at risk of two common pathogenic variants. Method: A pregnant woman carrying monozygotic twins opted for prenatal testing as she and her partner were heterozygote carriers of F508del (c.1521:1523del). The partner was also positive for the CFTR-related va...

Introduction: Length of hospital stay after birth has decreased during the last decades, but nationwide data on length of hospital stay after cesarean section are lacking. Elements of Enhanced Recovery Programs were reported to reduce the length of hospital stay. The aim of this nationwide study was to describe the length of hospital stay after ce...

Background Dystocia is one of the most common causes of cesarean section in nulliparous women. Studies have described the presence of vitamin D receptors in the myometrium, but it is still unclear whether vitamin D affects the contractility of the smooth muscles. We therefore aimed to determine the association between the vitamin D serum level at l...

Introduction Recent studies in in vitro fertilisation (IVF) patients have associated abnormal vaginal microbiota (AVM) with poor clinical pregnancy rates of 6%–9% per embryo transfer. The biological plausibility for this finding is hypothesised to be ascending infection to the endometrium which in turn hampers embryo implantation. New molecular bas...

Introduction: Fetal heart rate variability (FHRV) evaluates the fetal neurological state, which is poorly assessed by conventional prenatal surveillance including cardiotocography (CTG). Accurate FHRV on a beat-to-beat basis, assessed by time domain and spectral domain analyses, has shown promising results in the scope of fetal surveillance. Howeve...

In two cases, cell‐based noninvasive prenatal testing (cbNIPT) detected pathogenic copy number variations (CNVs) in the fetal genome. cbNIPT may potentially be an improved noninvasive alternative for the detection of smaller CNVs. In two cases, cell‐based noninvasive prenatal testing (cbNIPT) detected pathogenic copy number variations (CNVs) in the...

Objective To evaluate whether systematic antepartum screening for Group B Streptococci (GBS) by urine culture improves the risk factor‐based selection of pregnant women for intrapartum GBS screening with a rapid polymerase chain reaction (PCR) assay. Methods A prospective observational study was conducted between April 2013 and June 2014. GBS colo...

Cell-based non-invasive prenatal testing (cbNIPT) based on circulating fetal extravillous trophoblasts (fEVTs) has shown to be possible in gestational week (GW) 10–13. Prenatal testing is relevant for a wider time period than GW 10–13, but it is unclear if fEVTs are present in sufficient numbers for cbNIPT at other time points during pregnancy. We...

( BJOG . 2019;126:1015–1023) Major postpartum hemorrhage contributes to almost a quarter of worldwide maternal deaths. Effective management and team collaboration could reduce mortality. Competencies supporting successful performance of teams during time-critical and stressful moments are referred to as nontechnical skills. During postpartum hemorr...

Introduction: Circulating fetal extravillous trophoblasts may offer a superior alternative to cell-free fetal DNA for noninvasive prenatal testing. Cells of fetal origin are a pure source of fetal genome, hence, unlike cell-free noninvasive prenatal test, fetal cell-based noninvasive prenatal test is not expected to be affected by maternal DNA. Ho...

Background When determining optimal treatment regimens, patient reported outcomes including satisfaction are increasingly appreciated. It is well established that the birth experience may affect the postnatal attachment to the newborn and the management of subsequent pregnancies and deliveries. As we have no robust validated Danish tool to evaluate...

Background Cortisol has been used to capture psychophysiological stress during childbirth and postpartum wellbeing. We explored the effect of a brief antenatal training course in self-hypnosis on salivary cortisol during childbirth and 6 weeks postpartum. Methods In a randomized, controlled trial conducted at Aarhus University Hospital Skejby Denm...

Background The frequency of induction of labour (IOL) in late-term pregnancy has increased significantly, but little is known about how women with uncomplicated pregnancies experience IOL for late-term indication alone. Aim To explore how women with uncomplicated pregnancies experienced late-term IOL. Methods Qualitative interviews were conducted...

Background The aim of this systematic review was to describe the effects of drug exposure during pregnancy on fetal cardiac function. Methods We searched MEDLINE, Embase, Cochrane and SCOPUS for studies assessing fetal cardiac function in drug-exposed human pregnancies. Risk of bias was assessed by the Risk Of Bias In Non-randomized Studies of Int...

Using self‐reports and blood samples from 225 unselected Danish first trimester pregnant women, the purpose of this study was to assess their use of stimulants e.g. caffeine and nicotine as well as over‐the‐counter (OTC) and prescription drugs. According to self‐reported information, 24% had used prescription drugs and 48% had used OTC drugs mainly...

Background: Non-obstetric surgery conducted during pregnancy may increase the risk of adverse birth outcomes like small for gestational age, preterm birth, and miscarriage. Mechanisms are unclear but possibly longer lasting. We examined whether appendectomy, cholecystectomy and diagnostic laparoscopy conducted before pregnancy affect these outcome...

Introduction: Hypertensive disorders of pregnancy, including gestational hypertension and preeclampsia, are leading causes of morbidity and mortality for both mother and fetus. It has been proposed that vitamin D affects a number of biological processes involved in the pathogenesis of hypertensive disorders of pregnancy. Therefore, a seasonal vari...

Introduction: In pregnant women, bacteriuria with group B streptococci (GBS) may be associated with a high degree of recto-vaginal GBS colonisation and therefore an increased risk of early-onset GBS disease. The aim of this study was to assess the performance of routine use of dipstick urine analysis during pregnancy for prediction of recto-vagina...

Introduction: Whether there is an association between residual myometrial thickness (RMT) after cesarean section (CS) and the risk of uterine rupture (UR) or uterine scar dehiscence at the subsequent delivery has been sparsely investigated. Materials and methods: Our cohort included 149 women with a first CS in whom we measured RMT by transvaginal...

Objectives: To investigate the association between neonatal complications and neurophysiological development in twins at 18 and 48–60 months of age. Methods: This was a secondary analysis of 841 Danish mono- and dichorionic diamniotic twins from a randomized controlled trial (PREDICT study), which included an assessment of the twin’s neurophysiolog...

Introduction: Surgery during pregnancy may increase the risk of adverse birth outcomes. In this nationwide registry-based cohort study including women aged 15-54 years with singleton birth or miscarriage, we examined the association between non-obstetric abdominal surgery during pregnancy and the birth outcomes small for gestational age, preterm b...

Background: Preeclampsia is a serious medical disorder affecting pregnancy. Screening in early pregnancy can identify women at risk and enable effective prophylactic treatment. Accurate blood pressure (BP) measurement is an important element of the screening algorithm. Automated self-screening, while attending the first trimester ultra sound scan,...