An interventional study of Elective induction of labor at 39 gestational weeks and 0 to 3 days in Pregnancy, Obesity and Parturition, sponsored by University of Aarhus. Recruiting at 12 sites in Denmark. Open to female participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-06-26.
Sponsored by University of Aarhus · Not applicable, Interventional, and Treatment
The rate of overweight and obese women becoming pregnant is increasing. Obesity in pregnancy along with delivery by cesarean section in obese women is associated with several complications as compared to normal weight women. The longer the woman is pregnant, the longer she is at risk. In an otherwise low-risk pregnant woman at term, it is an ongoing clinical dilemma, whether the benefits of elective induction of labor and termination of the pregnancy will outweigh the potential harms from concomitant induction and delivery process. The proposed study is a randomized controlled study of elective induction versus expectant management in obese women. The study will be carried out as a national multicenter study with inclusion of 1900 participants from Danish delivery wards. The null hypothesis is that the caesarean section rate is similar with elective induction of labor at 39 weeks of gestation, compared with expectant management among pregnant women with pre- or early pregnancy BMI≥30.
Background The World Health Organization (WHO) defines overweight as a body mass index (BMI) of ≥25 kg/m2 and obesity as a BMI of ≥30 kg/m2. Overweight and obesity are rising dramatically worldwide. In fertile women, the prevalence of obesity is one third in the United States, 20% in the United Kingdom, and 12-13% in Denmark. The association between obesity in pregnancy and the risk of gestational complications increases with increasing BMI. Among other complications, obesity in pregnancy is associated with increased risk of caesarean delivery. Delivery by caesarean section further adds significant risks of wound infection or other infectious morbidity in obese women as compared to normal weight women. The longer the woman is pregnant, the longer the risk of pregnancy complications remains. In an otherwise low-risk pregnant woman at term, it is an on-going clinical dilemma, whether the benefits of elective induction of labor (eIOL) and termination of the pregnancy will outweigh the potential harms from the concomitant induction and delivery process. Regarding delivery complications, based on data from historical cohorts, eIOL has traditionally been associated with an increased risk of caesarean section and instrumental delivery. Therefore, expectant management has been the preferred clinical option. This interpretation has now been challenged by a randomized trial (ARRIVE) with >6000 low-risk pregnant women where eIOL at 39 weeks of gestation was associated with lower caesarean delivery rates. There are no randomized studies in obese women, but two larger observational studies did find lower odds of caesarean delivery in obese women with eIOL as compared to awaiting labor onset. Hence, a randomized trial that would compare caesarean delivery among obese women whose labor is induced with those expectantly managed is warranted. The proposed study will provide new and important knowledge into the area of induction of labor among overweight and obese women with potential great international impact for the future raising number of pregnant women in this subgroup.
With this trial, the investigators aim to compare the risk of caesarean section in obese (BMI ≥ 30 kg/m2), but otherwise low-risk women with eIOL as compared to expectant management.
Materials and methods
The study is a multicenter randomized controlled trial with an allocation ratio of 1:1 in the two following arms:
Comparison arm/expectant management: Waiting for spontaneous onset of labor unless a situation develops necessitating either induction of labor or caesarean section.
1900 low-risk pregnant women with a pre- or early pregnancy BMI ≥ 30 carrying a singleton pregnancy will be recruited from the Danish delivery wards. In each trial site, a physician investigator will be responsible for the enrolment, the electronically randomization, and data collection.
The primary endpoint is the caesarean section rate. Among others there will be secondary endpoints on instrumental delivery, onset of labor, methods of induction, perinatal and postpartum complications both maternal and neonatal along with data on women's experience on birth measured by a questionnaire survey four to six weeks post-partum.
Ethics The study will be conducted in accordance with the ethical principles outlined in the latest version of the 'Declaration of Helsinki' and the 'Guideline for Good Clinical Practice' related to experiments on humans. The Central Denmark Region Committee on Biomedical Research Ethics, and The Danish Health Authorities have approved the study.
Perspectives In perspective, more than 39% of the world's population is overweight and 13% are obese by the WHO classification. Pregnant overweight women are at increased risk of pregnancy and delivery complications, and there is a need to improve maternity care for this subgroup of women. The results of this trial have the potential to generate important knowledge for the improvement of delivery in obese women and they will add key information to an on-going discussion of the effects of labor induction before term. Any possible harm or disadvantage to the individual study participant is outweighed by the possible benefit to the increasing number of obese women who will be pregnant in the future.
6,296 studies on the registry are indexed under Obesity; 1,695 are open to participants now.
This study's planned enrollment of 1,900 is above the median of 78 across 4,878 interventional studies indexed under Obesity.
Browse Obesity studies →University of Aarhus is the lead sponsor of 1,274 studies on the registry; 183 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Elective induction of labour at 39 gestational weeks and 0 to 3 days.
Procedure: Elective induction of labor at 39 gestational weeks and 0 to 3 days
Awaiting spontaneous labor.
Elective induction of labor (eIOL) according to local policies
Also known as: eIOL
Caesarean section
number (no.)
Time frame: At delivery
Mode of delivery if not by caesarean
* Vaginal delivery - no. * Vaginal assisted delivery - no.
Time frame: At delivery
Mode of delivery
* Caesarean section - percent * Vaginal delivery - percent * Vaginal assisted delivery - percent
Time frame: At delivery
Vaginal assisted delivery
* Forceps - no. * Ventouse - no.
Time frame: At delivery
Indication for caesarean section (more than one indication is possible)
* Labour dystocia - no. * Fetal distress - no. * Maternal request - no. * Suspected macrosomia - no. * Non-cephalic presentation - no. * Extensive vaginal bleeding - no. * Suspected uterine rupture - no. * Maternal or fetal complication/condition (free text) - no. * Other indication for caesarean section (free text) - no.
Time frame: At delivery
Indication for vaginal assisted delivery (more than one is possible)
* Labour dystocia - no. * Fetal distress - no. * Maternal request - no. * Other indication for assisted vaginal delivery (free text) - no.
Time frame: At delivery
Use of epidural
no.
Time frame: At delivery
Damage to internal organs (bladder, bowel or ureters)
no.
Time frame: At delivery to 30 days postpartum
Uterine scar dehiscense or rupture
no.
Time frame: At delivery
Complications
* Minor shoulder dystocia defined as the need for McRobert's maneuver - no. * Major shoulder dystocia defined as the need for procedures other than McRobert's maneuver - no. * Clinical suspicion of abruption of the placenta leading to an intervention in labour - no. * Cord prolapse - no. * Maternal fever defined as temperature \>38,2 / \>38,0 degrees celsius with / without epidural - no. * Perineal 3rd degree laceration - no. * Perineal 4th degree laceration - no. * Episiotomy - no.
Time frame: At delivery
Postpartum haemorrhage
* Blood loss \>500ml - no. * Blood loss \>1000ml - no. * Blood transfusion - no. Time Frame \[0-2 days postpartum\]
Time frame: 0-2 hours postpartum
Hysterectomy
no.
Time frame: At delivery to 30 days postpartum
Postpartum morbidity
* Puerperal infection treated in hospital - no. * Other severe postpartum conditions treated in hospital (free text) - no.
Time frame: 0-30 days postpartum
Maternal admission to Intensive Care Unit
no.
Time frame: Enrollment to 30 days postpartum
Maternal cardiopulmonary arrest
no.
Time frame: Enrollment to 30 days postpartum
Maternal death
no.
Time frame: Enrollment to 30 days postpartum
Primary neonatal composite including any of the following;
* Perinatal death (stillbirth and neonatal) * The need for respiratory support if admitted to a neonatal department (intubation and mechanical ventilation, oxygen, continuous positive airway pressure (CPAP), or high-flow nasal cannula (HNFC)). Time Frame \[within 72 hours after birth\] * Apgar score \< 4 at 5 minutes * Hypoxic-ischemic encephalopathy (defined as the need for therapeutic hypothermia) * Seizures * Infection (defined as antibiotic treatment continuously for 7 days minimum) * Meconium aspiration syndrome * Birth trauma (bone fracture, Duchenne-Erbs palsy, or retinal hemorrhage) * Intracranial or subgaleal hemorrhage * Hypotension requiring vasopressor support
Time frame: Enrollment to 28 days of life
Components of the primary neonatal composite will additionally be reported separately
* Perinatal death (stillbirth and neonatal) - no. * The need for respiratory support if admitted to a neonatal department (intubation and mechanical ventilation, oxygen, continuous positive airway pressure (CPAP), or high-flow nasal cannula (HNFC)). Time Frame \[within 72 hours after birth\] - no. * Apgar score \< 4 at 5 minutes - no. * Hypoxic-ischemic encephalopathy (defined as the need for therapeutic hypothermia) - no. * Seizures - no. * Infection (defined as antibiotic treatment continuously for 7 days minimum) - no. * Meconium aspiration syndrome - no. * Birth trauma (bone fracture, Duchenne-Erbs palsy, or retinal hemorrhage) - no. * Intracranial or subgaleal hemorrhage - no. * Hypotension requiring vasopressor support - no.
Time frame: Enrollment to 28 days of life
Neonatal trauma composite including any of the following;
* Birth trauma (bone fracture, Duchenne-Erbs palsy, or retinal hemorrhage) * Intracranial or subgaleal hemorrhage
Time frame: At delivery to 28 days of life
Neonatal asphyxia composite including any of the following;
* Apgar score \< 4 at 5 minutes * Umbilical cord pH-value \< 7.0 (allow missing data) * Umbilical cord standard base excess (sBE) \< -15.0 mmol/l (allow missing data) * Seizures * Hypoxic-ischemic encephalopathy (defined as the need for therapeutic hypothermia)
Time frame: At delivery to 28 days of life
Apgar score at 5 minutes
* Apgar score \<4 - no. * Apgar score of 4-7 - no.
Time frame: 5 minutes of life
Umbilical cord arterial and venous blood sample (allow missing data)
* pH-value \< 7.0 - no. * sBE \< -15.0 mmol/l - no.
Time frame: 0-30 minutes of life
Neonatal admission
no.
Time frame: 0-72 hours of life
Respiratory support during neonatal admission
* CPAP (y/n) - no. * HNFC (y/n) - no. * Oxygen supplement treatment (y/n) - no. * Ventilator treatment (y/n) - no.
Time frame: 0-28 days of life
Other treatment during neonatal admission
* Therapeutic hypothermia (y/n) - no. * Vasopressor support (y/n) - no. * Antibiotic treatment continuously for 7 days minimum (y/n) - no.
Time frame: 0-28 days of life
Neonatal characteristics 1
* Female sex - no. * Birth weight \> 4500 grams (y/n) - no.
Time frame: At delivery
Neonatal characteristics 2
\- Mean birth weight - grams
Time frame: At delivery
Maternal experience on birth
Childbirth Experience Questionnaire Scoring range is 1 to 4 where higher ratings reflect more positive experiences
Time frame: 4-6 weeks postpartum
Maternal postnatal depression
* Major Depression Inventory (MDI) * Edinburgh Postnatal Depression Score Scoring range is 1 to 4 where higher ratings reflect more positive experiences
Time frame: 4-6 weeks postpartum
Documents are hosted by the registry — open the source record to download them.
Plan to share: Yes — The final dataset will be publicly available in an anonymised form using an open data repository (i.e. CERN) or another equivalent database. All relevant trial-related documents will be shared along with the data.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
University of Aarhus