Background:

Secretory activation is characterized biochemically in human milk by a fall in sodium concentration, an increase in potassium concentration, and a decreased sodium to potassium ratio. These markers can be used to identify a delay in secretory activation which can result from hormonal birth control.

Research Aim:

To evaluate if the insertion of the Etonogestrel implant early in the postpartum period would delay the time to secretory activation as measured by biochemical markers.

Methods:

We conducted a prospective, longitudinal, non-randomized, observational cohort study. Women with singleton pregnancies were identified as wanting either no birth control or the Etonogestrel implant in the postpartum period. Human milk samples were collected starting at 12 hours after delivery, and then in 12-hour increments. Samples were tested for sodium and potassium levels.

Results:

As in the unadjusted models, there was evidence of a difference in sodium levels at two days postpartum, with the sodium level higher by 32.29 mM (95% CI [7.39, 57.20], p = .013) in the implant group than in the no birth control method group. A difference at day 2 was observed in the ratio (sodium/potassium) levels, with a higher mean ratio in the implant group by 2.49 (95% CI [0.14, 4.85], p = .039). For potassium levels, the only difference was observed at day 4, with lower values in the implant group (p = .045).

Conclusion:

The transition from colostrum to copious milk secretion is delayed by the early insertion of the Etonogestrel device. This is evidenced by the delay in biochemical markers normally seen in secretory activation.

中文翻译：

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产后依托孕烯植入及其对分泌激活生化标志物的影响：初步研究

背景：

人乳中分泌激活的生化特征为钠浓度下降、钾浓度升高和钠钾比降低。这些标记可用于识别可能由激素节育引起的分泌激活延迟。

研究目的：

评估在产后早期植入依托孕烯植入物是否会延迟分泌激活的时间（通过生化标记物测量）。

方法：

我们进行了一项前瞻性、纵向、非随机、观察性队列研究。单胎妊娠的妇女被确定为在产后期间不想要节育或依托孕烯植入物。在分娩后 12 小时开始收集母乳样本，然后以 12 小时为增量进行收集。测试样品的钠和钾水平。

结果：

与未经调整的模型一样，有证据表明产后两天的钠水平存在差异，植入组的钠水平比植入组高 32.29 mM（95% CI [7.39, 57.20]，p = .013 ）无节育组。观察到第 2 天的比率（钠/钾）水平存在差异，植入物组的平均比率更高 2.49（95% CI [0.14, 4.85]，p = .039 ）。对于钾水平，唯一的差异是在第 4 天观察到的，植入组的值较低 ( p = .045)。

结论：

依托孕烯装置的早期插入延迟了从初乳到大量乳汁分泌的转变。通常在分泌激活中看到的生化标记物的延迟证明了这一点。