Follicular phase, menstrual cycle effects

The results 68% of the women treated with extracts from the follicular phase of the menstrual cycle shortened their own current cycle by an average of 1.7 days. A different 68% of the women treated with extracts from the ovarian phase of the menstrual cycle lengthened their own current cycle by an average of 1.4 days. Finally, underarm extracts taken following ovulation, in the luteal phase, had no effect on the... 

In a later experiment, two pheromones from axillary odor of young women influenced the estrus cycle of other women (Stern and McClintock, 1998). Armpit secretion that appears odorless to humans was applied daily between the upper lip and nose of healthy young women and had two opposite effects depending on the menstrual phase of the odor donors. Secretion from nine donor women, collected on pads in their armpits during the follicular phase of their cycles... 

A loss of primary oocytes will irreversibly affect a woman s fecundity, but this is difficult to measure directly. Reproductive dysfunction can be studied by the evaluation of irregularities of menstrual cycles and onset of menarche and menopause. However, menstrual cyclicity and onset of menopause and menarche are affected by many parameters, such as age, genetics, nutritional status, stress, exercise, certain drugs and the use of contraceptives that alter endocrine feedback. The length of the menstrual cycle, particularly the follicular phase (before ovulation), can vary between individuals and may make it difficult to measure significant effects in groups of women (Burch et al., 1967 Treloar et al., 1967). 

Melatonin affects reproduction in seasonally breeding animals. In humans, findings of increased endogenous melatonin in hypogonadism and low concentrations in precocious puberty imply an interaction between melatonin and gonadotropins however, data on the effects of exogenous melatonin are limited (1). In a randomized study in 16 women, melatonin enhanced LH and FSH responses to submaximal GnRH stimuli in the follicular but not the luteal phase of the menstrual cycle (24). 

The subjective and behavioral effects of triazolam were investigated in 20 healthy women, who took oral triazolam 0.25 mg or placebo at the follicular, periovulatory, and luteal phases of their menstrual cycle in a within-subject design (12). After triazolam most of them reported the expected increases in fatigue and decreases in arousal and psychomotor performance. Neither plasma concentrations of triazolam nor mood and performance differed across the three phases. This study shows that the effects of triazolam are highly stable across the menstrual cycle. 

Following the pioneering work on menstrual synchrony by Stern and McClintock [270, 271], it has been odourless axillary compounds fi om the armpits of women in the late follicular phase of their menstrual cycles accelerated the preovulatory surge of luteinizing hormone of recipient women and shortened their menstrual cycles. Axillary compounds from the same donors which were collected later in the menstrual cycle (at ovulation) had the opposite effect they delayed the luteinizing hormone surge of the recipients and lengthened their menstrual cycle [271]. The... 

Reproductive Effects. In samples from more than 200 men, no correlation between seminal fluid selenium and sperm count or mobility was detected. No significant increase in spontaneous abortions was reported among women chronically exposed to drinking water containing excessive amounts of selenium. Oral or injection treatment of rats with sodium selenate or selenite (at doses at least 8 times greater than those normally supplied by an adequate diet) has been shown to increase the number of abnormal sperm, produce testicular hypertrophy, or degeneration and atrophy in males, and to affect the estrous cycle in females. The animals in these studies were not mated, so it is not clear if fertility was affected. A small increase in the number of abnormal length estrous cycles was observed in mice exposed to selenium. Disturbances in the menstrual cycle (anovulation, short luteal and follicular phases) were also observed in monkeys treated orally with L-selenomethionine. Selenium deficiency has also been reported to cause decreased sperm production and motility in rats. The relevance of these reproductive effects of selenium in laboratory animals to potential reproductive effects in humans is not known. 

The PA mifepristone also delays or inhibits ovulation, which may produce amenorrhea [48, 49]. Amenorrhea may be a consequence of an effect at the level of the ovary, pituitary or hypothalamus. The SPRM asoprisnil, in contrast, is not so effective in inhibiting ovulation [50]. The amenorrhea consequent to PAs and SPRMs occurs with levels of estradiol in the range of the early follicular phase of the menstrual cycle [48-50]. As a result ofthe antiproliferative effect and the amenorrhea, PAs and SPRMs have been advocated in the treatment of uterine myoma, endometriosis and dysfunctional uterine bleeding. 

Menstruation marks the start of the menstrual cycle. During the follicular (or proliferative) phase, estrogen stimulates proliferation and differentiation. One important effect of estrogen in the endometrium and other tissues is induction of the progesterone receptor (PR), which enables cells to respond to this hormone during the second half of the cycle. 

CiciNELLi et al. [5] described an interesting pattern of collateral flow between the uterine and ovarian arterial supply to the uterus. In doing measurements of blood flow in premenopausal women, this group found there is more blood flow to the uterus from the ovarian artery during the follicular phase, whereas in the luteal phase most of the uterus is supplied from the uterine artery. Whether this change in blood flow patterns is changed in patients with fibroids is not clear. No studies of the effect of the phase of the menstrual cycle on the effectiveness of uterine artery embolization have been performed at this point. 

These findings might have practical implications thus, dietary fiber is known to decrease intestinal transit[122] and, as already discussed, some dietary fiber seems to have a hypocholesterolemic effect. Moreover, Wald et al. recently reported that gastrointestinal transit time was prolonged in the luteal phase of menstrual cycle when compared to the follicular phase[123] finally, many gastrointestinal hormones have a definite effect on small bowel motility [124]. 

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