Outpatient Induction of Labor With Oral Misoprostol

Induction of labor is an increasingly used intervention in obstetrics due to expanding indications, which more often includes relatively healthy women with uncomplicated pregnancies. While induction of labor traditionally is offered in an inpatient setting, a shift towards an outpatient setting is increasing despite insufficient evidence regarding safety and effectiveness. Oral misoprostol is easy for the pregnant women to administer and the risk of uterine hyperstimulation with fetal heart rate changes is found to be low. Strong evidence concludes that oral misoprostol is preferable as an induction agent and is recommended by the World Health Organization (WHO).

The investigators will perform a multicenter randomized-controlled trial comparing labor induction in an outpatient versus inpatient setting, aiming to increase knowledge on outpatient induction of labor with oral misoprostol. The study is based on experiences and findings from a recently performed pilot trial and targets a large group of relatively healthy pregnant women where induction of labor is decided.

The investigators hypothesize that women induced in an outpatient setting will be more satisfied than women induced in an inpatient setting.

After induction of labor is decided the women will be recruited according to inclusion and exclusion criteria's.

The inpatient induction group will receive the following treatment:

Oral misoprostol 25ug every two hours and a cardiotocography for fetal monitoring every 4-6 hours until start of contractions, the next 48 hours while admitted to the maternity ward. The participating women will be transferred to the labor ward by start of contractions or need for closer fetal surveillance and/or analgesia.

The outpatient induction group will receive the following treatment:

These participating women receive the first oral misoprostol 25ug at the maternity unit. After two hours if the cardiotocograph is normal and there are no signs of contractions, these women go home. At home, the women will continue to take 25ug misoprostol every two hours until 22 pm or until the contractions begin. Maximum time spent at home is 48 hours and maximum number of tablets is 12 during this period (6 tablets each day). The women will also receive oral and written information regarding when to return to the maternity ward. Information sheets for the midwives and included women will be adapted from those used in the pilot study.

If the contractions are still absent after 48 hours or a maximum of 12 tablets (6 per day), all women (both inpatient and outpatient) are admitted to the maternity ward for further induction of labor. All women will receive equal standard of care including fetal surveillance after admittance to the hospital. Further follow up is in accordance with standard procedure of the maternity ward. Questions about fidelity to the proposed protocol across sites will be asked in the patient questionnaire.

Eligibility Criteria:
Inclusion Criteria:

* ≥ 37 gestational weeks, vertex presentation, single pregnancy
* Age ≥ 18 years
* Understand and read Norwegian
* Distance to hospital less than 1 hour
* Normal ultrasound including:

  * fetal movements
  * amniotic fluid (deepest single vertical pocket) \> 2 cm
  * estimated fetal weight ≥ -15% (≥ 10 percentile)
* Normal antenatal cardiotocography
* Women with stable hypertension and uncomplicated preeclampsia without indication for inpatient treatment can be included after individual assessment.
* Access to partner or contact person at home for transportation to hospital

Exclusion Criteria:

* Premature rupture of membranes
* Uterine scar
* BMI ≥ 40
* Abnormal fetal Doppler (if examined); umbilical artery pulsatility index ≥ 95 percentile and/or cerebroplacental ratio \<1
* Fetal anomaly or chromosomic / genetic disorder
* Grand multipara (P≥4)
* Cognitive barriers
* Pregnancy complications such as preeclampsia requiring in-hospital treatment, insulin dependent diabetes or other conditions associated with risk of fetal hypoxia during labor
* Signs of infection or serious health problems
* Favorable cervix and / or previous obstetric history providing contraindications for induction with misoprostol
* Combined risk factors, individually evaluated by the attending obstetrician