Oladapo OT, et al. - A systematic review is carried out to integrate available information on the cervical dilatation patterns amid spontaneous labour of 'low-risk' women with normal perinatal outcomes. In light of these outcomes, an expectation of a minimum cervical dilatation threshold of 1-cm/hour throughout the first stage of labour is unrealistic for most healthy nulliparous and parous women. These outcomes call into question the universal application of clinical standards that are conceptually based on an expectation of a linear labour progress in all women.

Methods

• For this research, they searched PubMed, EMBASE, CINAHL, POPLINE, Global Health Library, and reference lists of eligible studies.
• Observational studies and other study designs were selected for this study.
• Two authors extracted information on maternal qualities, labour interventions, duration of labour centimetre by centimetre; and from dilatation at admission through 10 cm.
• They pooled data across studies utilizing weighted medians and employed Bootstrap-t method to generate their corresponding confidence bounds.

Results

• In this study, they found seven observational studies depecting labour patterns for 99971 women met their inclusion criteria.
• The median time to advance by 1 cm in nulliparous women was longer than 1 hour until 5 cm was reached with markedly rapid progress after 6 cm.
• In parous women, similar labour progression patterns were seen.
• The 95th percentiles for both parity groups propose it is not uncommon for some women to reach 10 cm despite dilatation rates much slower than 1-cm/hour threshold for the most part of their labours.