Lactation and Fertility

  title={Lactation and Fertility},
  author={Alan S. Mcneilly},
  journal={Journal of Mammary Gland Biology and Neoplasia},
  • A. Mcneilly
  • Published 2004
  • Biology, Medicine
  • Journal of Mammary Gland Biology and Neoplasia
In almost all mammals lactation, or more correctly the suckling stimulus, induces a period of infertility designed to provide the optimal birth spacing for survival of the offspring. The duration of lactational infertility depends on the sucking activity of the young with little evidence to support a role for nutritional status. Suckling disrupts the normal pulsatile pattern of hypothalamic gonadotrophin releasing hormone (GnRH)2secretion resulting in reduced LH secretion from the pituitary… 

Lactational endocrinology: the biology of LAM.

  • A. Mcneilly
  • Biology
    Advances in experimental medicine and biology
  • 2002
The parameters that are observed, while adequate for many in the Western world, do not provide useful guidelines for others where the pattern of breastfeeding, and introduction of supplements varies from those commonly found in the authors' study groups.

Anatomy, Development, Histology, and Normal Function of the Ovary

The ovary’s developmental origins and functional roles are explored to highlight the complexity of this remarkable product of reproductive evolution.

Knowledge of lactational amenorrhea as a contraceptive method among mothers of infants aged 0-6 months in a district, Eastern Turkey

A rural area of Turkey, the use of LAM as a contraceptive method remains low, even though the breastfeeding ratio is high, and the state of knowledge among mothers of infants aged 0-6 months on lactational amenorrhea as a contraceptives method is evaluated.

Effect of lactation stage and concurrent pregnancy on milk composition in the bottlenose dolphin

Milk progesterone indicated that dolphins ovulated and conceived between 413 and 673 days postpartum, following an increase in milk energy density and in relation to the growth rates of calves.

Effect of delayed breeding on the reproductive performance of female mice.

Results show that delayed breeding in the mouse is associated with decreased reproductive performance and a shorter reproductive lifespan compared with females bred at an earlier reproductive age.

Prolactin, neurogenesis, and maternal behaviors

Body Image Dissatisfaction and Disordered Eating Behaviors in Mothers during Lactation Period

The present study was conducted to examine the relationship of body image dissatisfaction and disordered eating behaviors among women during lactation period that is, maximum two years after last

Early menopause, low body mass index, and smoking are independent risk factors for developing giant cell arteritis

There was a significant association between hormonal and reproduction related factors and the risk of developing giant cell arteritis in women given the diagnosis before the age of 70, suggesting a possible role of oestrogen deficiency in the pathogenesis of giant cellarteritis.

Parental and Mating Effort: Is There Necessarily a Trade‐Off?

The empirical evidence for trade-offs between mating and parental effort in males and females is examined and the importance of considering individual variation is highlighted, and how preferences in one sex may influence the existence and the interpretation of apparent trade-off in the other sex is explored.



Physiological Mechanisms Underlying Lactational Amenorrhea

The successful initiation of lactation which would lead to the potential of utilizing breastfeeding as contraceptive may require more attention to be paid to the establishment of non-stress release of oxytocin.

CHAPTER 46 – Suckling and the Control of Gonadotropin Secretion

The suppression of pulsatile luteinizing hormone secretion during lactation in the rat.

It was concluded that a two-pup suckling stimulus was sufficient to completely suppress pulsatile GnRH release without affecting pituitary function, whereas an eight-p up suckling stimuli also depressed pituitaries sensitivity to GnRH.

Pulsatile GnRH stimulates normal cyclic ovarian function in amenorrheic lactating postpartum women.

The postpartum period is characterized hormonally by elevated levels of PRL and low levels of gonadotropins and sex steroids, and eight exclusively breast-feeding women provided a uniform pulsatile GnRH stimulus to test this latter hypothesis, demonstrating a more rapid initial ovarian responsiveness in the breast- feeding group.

Nutrition and lactational control of fertility in red deer

It is suggested that the principal influence of low planes of nutrition is to increase the suckling frequency of the calf in response to a decrease in availability of milk.

Effect of breast-feeding patterns on human birth intervals.

The combined evidence suggests that the menstruating interval is associated with a reduction of fecundity which is less complete than it is during the phase of lactational amenorrhea.

Relationship of feeding patterns prolactin and resumption of ovulation postpartum.

The relationship between breast feeding prolactin serum levels and ovulation was assessed and serum levels of both LH and FSH were in the early follicular phase range both before and after ovarian activity resumed among the lactating women.

The 24 h pattern of pulsatile luteinizing hormone, follicle stimulating hormone and prolactin release during the first 8 weeks of lactational amenorrhoea in breastfeeding women.

The pattern of pulsatile LH secretion in relation to that of follicle stimulating hormone (FSH) and prolactin, and suckling and ovarian activity at 4 and 8 weeks postpartum in 20 fully breastfeeding women with lactational amenorrhoea is determined.


The data suggests that the failure to maintain ovarian follicular development post partum in breast feeding women may be due to a direct block of LH action at ovarian level, perhaps by the high levels of prolactin associated with lactation and an inability of the hypothalamic‐pituitary axis to maintain pulsatile secretion of LH in the face of the negative feedback effects of the increased oestrogen secretion resulting from the initiation of follicularDevelopment.