Induction of Labour in Aotearoa New Zealand A clinical practice guideline, 2019

Abstract

This guideline provides the most recent research evidence for clinical conditions where induction of labour (IOL) at term would be considered, and for methods of cervical ripening and starting induction of labour. A multidisciplinary Panel assessed quality of evidence and made recommendations, considering the Aotearoa New Zealand (NZ) context. This guideline is meant to be used by clinicians to inform shared decision-making with women and their whānau, and by district health boards to reflect on their current practice and align local guidelines with the national guideline to facilitate consistent practice. The quality of research evidence varied considerably. Generally, where there was sufficient Level 1 evidence available, then the Panel made a recommendation about induction of labour; where there was insufficient evidence to make a recommendation, or if the evidence was rated to be of low or very low quality, then the Panel made practice points. In some conditions where Level 1 evidence was reviewed, such as suspected macrosomia, and no medical indication, the Panel debated at length a recommendation to offer IOL, but decided by consensus that the evidence was insufficient for the NZ context (different population, different intervention, or outcomes not of sufficient effect) and made practice points instead. Practice points are designed to help guide clinical practice, and encourage further understanding and discussion about the diverse beliefs, traditions and aspirations held by many women, their partners, family and whānau. It is important to enable and respect a woman’s right to be fully informed about the quality of evidence underpinning a recommendation for induction of labour and be given the opportunity to make an informed choice. It is important to promote and support spontaneous onset of labour and physiological labour and birth. This guiding principle aligns with the International Childbirth Initiative which states “maternal and newborn health benefits from an evidence-based approach to care. Every MotherBaby should be protected from unnecessary and potentially harmful interventions, practices, and procedures and from both overuse and underuse of medical technology.” It is important to individualise all decisions about induction. Some women do not fit into any one category that in itself warrants IOL, but instead have several risk factors for adverse outcomes, which can be cumulative. Clinicians should document the rationale for recommending care that does not align with the guidelines. Early term birth (37 and 38 weeks’ gestation) is associated with poorer neonatal and childhood outcomes compared to babies born at 39 to 41 weeks’ gestation. Unless there is an evidence-based indication supporting earlier planned birth, continue expectant management to 39 weeks’ gestation or more. The Panel identified numerous research gaps and have identified that there is a lack of evidence for the following themes: • The benefits and harms of IOL or expectant management for several specific conditions • The benefits and harms of IOL or expectant management in women who have multiple risk factors for perinatal death • Women’s perspectives and experiences of IOL or expectant management • Trials of IOL or expectant management in the NZ maternity healthcare context The Panel recommends that all future research studies on IOL include outcomes listed in the Core Outcome Set on IOL (Dos Santos 2018), and that academics, clinicians, policy-makers and consumers undertake a research agenda priority setting process for NZ. Recommendations in brief Membrane sweeping is the only intervention shown to reduce the need for formal IOL. Consider offering membrane sweeping at term to reduce the frequency of pregnancy continuing beyond 41 weeks’ gestation. The only clinical indication where IOL has been shown to reduce perinatal death is in pregnancy at or beyond term. Offer IOL between 41+0 and 42+0 weeks’ gestation to women with an uncomplicated pregnancy. In women with pre-labour rupture of membranes at ≥ 37 weeks’ gestation, offer planned early birth (immediate intervention or intervention within 24 hours), to reduce the risks of maternal infectious morbidity, definite or probable early-onset neonatal sepsis, and NICU admission. In women with hypertension in pregnancy, the Panel endorses the recommendations from the NZ Ministry of Health clinical practice guideline. For cervical ripening, it is reasonable to offer any of: prostaglandin E2 (vaginal gel or controlled-release pessary), prostaglandin E1 analogue (misoprostol low-dose two-hourly in oral solution) or balloon catheter (single- or double-balloon), based on reason for IOL, maternal values and preferences, local resources, and practical considerations. For cervical ripening with single-balloon catheter, inflate greater than 30mL to increase the chance of vaginal birth in 24 hours, compared to 30mL or less. While it is recognised that cervical ripening in the setting of IOL in childbirth has not been listed as a registered indication for misoprostol use in NZ, it has been widely researched internationally. Should hospitals choose to use misoprostol, it is recommended they develop local guidelines in cooperation with their Pharmacy department.