McNeilly A S
Medical Research Council Reproductive Biology Unit, University of Edinburgh, Scotland.
Endocrinol Metab Clin North Am. 1993 Mar;22(1):59-73.
There is no doubt that suckling can cause a substantial delay in the resumption of fertility postpartum in all societies regardless of nutritional status. The variability in duration of infertility is directly related to the different patterns of suckling, an uncontrollable variable specific to the mother and child. Resumption of fertility proceeds in two parts, an initial phase of amenorrhea in which ovarian follicle growth is suppressed or attenuated followed by a resumption of menstrual cycles often associated with inadequate luteal function contributing to the reduced fertility of lactating menstruating women. Suckling appears to suppress the normal pattern of pulsatile release of GnRH and hence LH and prevents the normal growth of follicles. The normal positive feedback effect of estrogen on LH release is abolished, and estradiol exerts an enhanced negative feedback effect on both LH and FSH. Thus, while suckling continues, any follicle that starts to develop and secrete estradiol will inhibit further LH release and therefore stop growing. When suckling declines, the pulsatile pattern of LH returns to normal, sensitivity to estrogen negative feedback declines, and follicle growth can continue and ovulation will occur. Opiates do not appear to be mediators of the suckling-induced suppression of GnRH or the release of prolactin in women. There is no clear role for prolactin per se or nutritional status in the suppression of ovarian activity postpartum. Thus, while the suppression of fertility in breast-feeding women plays an extremely important role in limiting populations, the mechanism whereby the suckling stimulus from the nipple causes the disruption in GnRH release from the hypothalamus remains to be elucidated.
毫无疑问，在所有社会中，无论营养状况如何，哺乳都会导致产后生育能力的恢复大幅延迟。不孕持续时间的差异直接与不同的哺乳模式有关，这是母婴特有的一个无法控制的变量。生育能力的恢复分两个阶段进行，第一阶段是闭经，在此期间卵巢卵泡生长受到抑制或减弱，随后月经周期恢复，通常伴有黄体功能不足，导致哺乳期月经妇女的生育能力下降。哺乳似乎会抑制促性腺激素释放激素（GnRH）以及促黄体生成素（LH）的正常脉冲式释放模式，并阻止卵泡的正常生长。雌激素对LH释放的正常正反馈作用被消除，雌二醇对LH和促卵泡生成素（FSH）都产生增强的负反馈作用。因此，在哺乳持续期间，任何开始发育并分泌雌二醇的卵泡都会抑制LH的进一步释放，从而停止生长。当哺乳减少时，LH的脉冲式模式恢复正常，对雌激素负反馈的敏感性下降，卵泡生长可以继续并发生排卵。阿片类药物似乎不是女性中哺乳诱导的GnRH抑制或催乳素释放的介质。催乳素本身或营养状况在产后卵巢活动抑制中没有明确作用。因此，虽然哺乳期妇女的生育抑制在限制人口方面起着极其重要的作用，但乳头的哺乳刺激导致下丘脑GnRH释放中断的机制仍有待阐明。
