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According to the current definition, the second stage of labor starts from complete dilatation of the cervix until the delivery of the fetus. At this stage, the force of uterine contraction is considered to be the strongest. After the cervix has been fully dilated, the caregiver/nurse will provide guidance to the mother regarding the push technique for delivering the fetus. However, complications, such as uterine rupture, post-partum perineum tenderness and severe laceration, may occur in the premature push of the second stage with inadequate technique or posture. When the patient received analgesic medications during labor for minimizing pain, or other fetal/maternal causes leading to prolong labor, some patient may not be able to push correctly after dilatation of the cervix. Severe tiredness and fatigue may be experienced during such long period of labor, especially in those who started immediate push right after full dilatation. Therefore, some obstetrician chose to start guiding the patient push only when the cervix is fully dilated, decent of fetal head, and involuntary exertion sensation in order to decreased the side effect from painless medications and save energy.
Since the second stage of labor poses potential risks to both mother and fetus, it is especially critical to teach the patient the optimal time and correct way to start push. The purpose of this study was to investigate the maternal and fetal outcome in the puerpera who started to push when the second stage is reached (immediate pushing) comparing with push under the circumstance of fully dilated cervix, presenting part reach near introitus and involuntary exertion sensation (delayed pushing).
The Method and Analysis of Literature Review：
The search of literatures was conducted from Cochrane Library, EMBASE, PubMed, and Airiti Library (Chinese database) using the key words of “Labor stage, second”, “Delayed pushing”, “immediate pushing”, second stage, vaginal delivery, delay push, immediate push, without language restriction up to July, 2019. A total of 2,318 articles were retrieved. After deleting the duplicated articles, the title and abstracts of remaining study were reviewed based on the inclusion and exclusion criteria. In the end, there were 15 randomized controlled trials included in this study.
The included literatures were evaluated using Cochrane’s risk of bias tool for quality assessment by two independent reviewers (LT Szu, PU Zhou) and crosscheck after completion. In case of a discrepancy in opinion, a third person (PH Lin) served as a mediator, and a consensus was reached by discussion. In our review, distribution concealment and blinding of participants and personnel were given “unclear”. The extracted data was integrated and analyzed using Review Manager 5.3 (The Nordic Cochrane Centre, Copenhagen, Denmark, 2014) software.
There are 10 randomized controlled studies included in this review with total 3,525 participates. The results are the following: (1) Maternal outcomes: comparing immediate pushing, delayed pushing could decrease total pushing time for 25 minutes (95% confidence interval [confidence] Interval, CI]: -37.2 to -13.5). In addition, maternal postpartum fatigue score was 0.7 points lower than the immediate pushing group (95% CI -1.1 to -0.3). (2) Neonatal outcome (Apgar score at 1 minute), has shown a higher score (0.19 points) in delayed pushing group than immediate pushing group (95% CI 0.10 to 0.27).
Conclusions and Recommendations：
It has been shown that the optimal time for push at the second stage is when the cervix is fully dilated, presenting part is near introitus, and experience involuntary exertion sensation (delayed pushing). This pushing strategy can decrease the total pushing time and decrease tiredness after the delivery without having negative impact on fetal health condition and Apgar score. Therefore, we recommend the caregiver instructs the pushing time at optimal moment, which allows the patient having more resting time and saving more energy during the labor