Prepregnant Overweight and Obesity Diminish the Prolactin Response to Suckling in the First Week Postpartum

Chris L. Kjolhede; Kathleen M. Rasmussen

摘要

Objective . The population subgroups with the highest proportion of overweight and obese women often are characterized by the lowest rates of initiation and shortest durations of breastfeeding. We previously documented that these 2 population-level trends may be related. In a population of white women who lived in a rural area, we observed that prepregnant overweight and obesity were associated with failure to initiate and also to sustain lactation. The means by which being overweight or obese negatively affect lactational performance is unknown and likely to be multifactorial in origin, including the simple mechanical difficulties of latching on and proper positioning of the infant. In addition, we have shown that prepregnant body mass index (BMI) is negatively associated with the timing of lactogenesis II, the onset of copious milk secretion. Although the effects of obesity on the prolactin response to infant suckling have never been studied, we postulated that maternal obesity could compromise this important response. We proposed that this might occur because obesity alters the 24-hour spontaneous release of prolactin and also because prolactin secretion is blunted in response to various stimuli among obese subjects. The fall in progesterone concentration that occurs immediately postpartum is the trigger for the onset of copious milk secretion, but maintenance of prolactin and cortisol concentrations is necessary for this trigger to be effective. Adipose tissue concentrates progesterone. We proposed that this additional source of progesterone would lead to consistently higher progesterone concentrations among obese compared with normal-weight women. This, in turn, would lead to a delay in reaching the appropriate concentration to trigger the onset of lactogenesis II. We tested the hypotheses that a reduced prolactin response to suckling and higher-than-normal progesterone concentration in the first week after delivery might be among the means by which maternal overweight could compromise early lactation.Methods . We enrolled 40 mothers of term infants from the same population that we studied previously. We measured serum prolactin and progesterone concentrations by radioimmunoassay before and 30 minutes after the beginning of a suckling episode at 48 hours and 7 days after delivery. We used path analysis to develop a parsimonious multivariate prediction of the prolactin response to suckling at 48 hours and 7 days postpartum.Results . As expected, prolactin values decreased from 48 hours to 7 days postpartum. Women who were overweight or obese (using the Institute of Medicine’s cutoff for women of a BMI 26 kg/m2) before conception had a lower prolactin response to suckling than normal-weight women at 48 hours but not at day 7. In multivariate analyses, overweight/obesity, primiparity, and birth weight were negatively associated with the prolactin response to suckling at 48 hours. After adjustment for confounding by time since delivery and the duration of the nursing episode, only overweight/obesity remained a significant negative predictor of prolactin response to suckling at day 7. Concentrations of progesterone decreased dramatically from 48 hours to 7 days postpartum but did not differ between normal-weight and overweight/obese women at either time. In addition, the decreases in progesterone concentrations from 48 hours to 7 days postpartum did not differ between the prepregnant BMI groups.Conclusion . The unique and important finding from this study is that overweight/obese women had a lower prolactin response to suckling. This would be expected to compromise the ability of overweight/obese women to produce milk and, over time, could lead to premature cessation of lactation. These findings are important because, during our observation period (just before and after lactogenesis II, the time of onset of copious milk secretion), the prolactin response to suckling is more important for milk production than it is later in lactation. We have previously shown that a high proportion of the overweight and obese women in this population who give up on breastfeeding do so at this time. This finding thus provides evidence of a biological basis for this association, and additional study of it is likely to be informative. We postulated that there would be consistently higher progesterone concentrations in the early postpartum period among obese compared with normal-weight women because adipose tissue is an extraplacental source of this hormone. This hypothesis was not supported in this study because there were no significant differences between normal-weight and overweight/obese women in progesterone concentrations at either 48 hours or 7 days postpartum. The values that we observed at these times were similar to those reported by others in the early postpartum period. The findings from this study add plausibility to our observation that initiation, not just duration of breastfeeding, is negatively affected by

机译：客观的。具有最高比例的超重和肥胖女性的人口亚组经常以最低启动和最短母乳喂养持续时间的特征。我们以前记录过这两种人口级趋势可能是相关的。在一个住在农村地区的白人妇女中，我们观察到预妊娠超重和肥胖与未能启动和维持哺乳期有关。超重或肥胖对泌乳性能产生负面影响的方法是未知的并且可能是多重的原点，包括锁存和适当定位婴儿的简单机械困难。此外，我们已经表明，预胶体体重指数（BMI）与生成的乳酸II的时序负相关，即大量乳汁分泌。虽然肥胖对患有婴儿哺乳的催乳素反应的影响从未被研究过，但我们假设产妇肥胖可能会损害这一重要的反应。我们提出这种可能发生这种情况，因为肥胖改变了催乳素的24小时自发释放，并且由于醇溶蛋白分泌术后倾向于肥胖的刺激。产后发生的黄体酮浓度下降是对大量乳汁分泌发作的触发，但是这种触发有效的催乳素和皮质醇浓度的维持是必需的。脂肪组织浓缩黄体酮。我们提出，与正常重量女性相比，这种孕酮的额外来源将导致肥胖中的肥胖孕浓度始终如一。反过来，这将导致延迟达到适当的浓度，以触发泌乳生成的发作II。我们测试了在递送后的第一周中对乳酸和高于正常的黄体酮浓度的降低的假设可能是母亲超重可能会损害早期乳液的方法中。我们从先前学习的相同人群中注册了40名母亲的婴儿。在递送后48小时和7天后，通过放射免疫测定血清催乳素和孕酮浓度测量血清催乳素和孕酮浓度。我们使用路径分析来制定催乳素对乳酸乳酸乳蛋白反应的促进多变量预测，在第48小时和7天后的第7天。结果。正如预期的那样，催乳素值从产后48小时减少到7天。超重或肥胖的女性（使用医学院为BMI> 26kg / m2的女性）在受孕之前对乳酸率低，而不是在48小时的正常重量妇女，但第7天没有。在多元分析中，超重/肥胖，孕产性和出生体重与催乳素反应在48小时内与乳酸反应负相关。在调整混淆后，自发出和护理发作的持续时间进行了混淆，只有超重/肥胖仍然是催乳素的重要预测因素，在第7天对乳酸的反应仍然是乳酸的反应。孕酮的浓度从产后的48小时到7天急剧下降，但没有差异在两次正常重量和超重/肥胖的女性之间。此外，产后48小时至7天的孕酮浓度的降低在预胶粘剂BMI基团之间没有区别。结论。本研究的独特又重要的发现是超重/肥胖女性对哺乳的反应较低。预计这将损害超重/肥胖女性生产牛奶的能力，随着时间的推移，可能导致哺乳期的过早停止。这些发现很重要，因为在我们的观察期间（仅仅在生殖器II之前和后期后，发病时间发生了大量乳汁分泌时），对乳酸的催乳素反应比哺乳期后来更重要。我们此前表明，在这次放弃母乳喂养的人口中的超重和肥胖女性的高度比例很高。因此，这一发现提供了这种关联的生物学基础的证据，并且对其的额外研究可能是信息性的。我们假设与正常重量妇女相比，肥胖的产后早期的孕孕期浓度始终如一，因为脂肪组织是这种激素的含水性来源。本研究不支持该假设，因为在产后的48小时或7天的孕酮浓度下正常重量和超重/肥胖女性之间没有显着差异。我们在这些时间观察到的价值观与产后早期其他人报告的值类似。本研究的发现为我们的观察结果添加了符号，而不是仅母乳喂养的持续时间受到负面影响

Prepregnant Overweight and Obesity Diminish the Prolactin Response to Suckling in the First Week Postpartum

摘要

著录项

相似文献

相关主题

期刊订阅