What is happening with female hormones that mess with the sleep process?
Let's review a typical menstrual cycle first.
Generally speaking, the menstrual cycle describes the full range of hormonal shifts generated by the body over a typical four-week period (of course, this varies widely from one individual to the next, but for our purposes, we're calling the cycle a 28-day one).
Menstruation involves several key organs: the ovaries, the uterus and endometrium, the vagina and the cervix.
The ovaries house a female's eggs; she is born with all of these, but they are not mature and will not be released until puberty, after new hormones flood the bloodstream and prompt their maturity. They are then distributed monthly over the reproductive lifespan of the female for the purpose of reproduction.
The uterus is the womb, the large organ meant to house and grow a fetus from a fertilized egg or embryo to a full-grown baby. Its lining is known as the endometrium.
The vagina is the passageway that connects the interior of the women's reproductive system to the body's exterior.
The cervix is the opening between the vagina and the uterus; think of it as a gatekeeper that opens more easily during the most fertile time, but is less accessible during the infertile stages of one's menstrual cycle.
Let's talk about hormones now.
The ovaries also release varying amounts of two key hormones to help regulate this process: estrogen and progesterone. Their levels in the bloodstream influence the quality of the lining of the uterus as well as the quality of the cervix. Both organs are extremely sensitive to this changing chemistry. These two hormones work in synch to prepare all the female reproductive organs for the potential implantation of a fertilized egg. When no eggs are fertilized, the lining of the uterus sheds via the blood and other fluids and tissues that have collected there over the cycle (this is what we think of as our "period,") and then a new cycle begins.
Estrogen is responsible for helping the body to develop all the accessory organs of the reproductive system (the uterus, the breasts, pubic hair, fatty deposits along the hips and breasts) as well as encourage the widening of the pelvis in preparation of a potential pregnancy. Estrogen also plays a role in metabolism. But you can think of estrogen as the harbinger of puberty.
Progesterone is the key hormone for the growth of the embryo, so it plays a much larger role during pregnancy than at other times, by inhibiting contractions in the uterus during pregnancy and helping the breasts to develop milk. However, progesterone during pregnancy is no longer produced by the ovaries, but by the placenta, the sac inside which the embryo grows.
The first five days of the cycle are called the menstrual phase. This is the actual "period" part of menstruation, where blood and cells are sloughed away from the lining of the uterus and voided through the vagina as "flow." There is a major drop in progesterone at this time due to the absence of an implanted embryo. This is a time of infertility with no ovarian activity.
From days 6 through 14, the proliferative phase, estrogen production amps up, stimulating the process of relining the uterus. This is the fertility period, in which eggs in the ovary are developed and released for potential fertilization (usually around day 14). Another hormone is responsible for this process: follicle-stimulating hormone (FSH). It helps to mature eggs in the ovary. Because of FSH, there is more mucus in the cervix, which will also dilate somewhat and soften to receive released eggs for potential fertilization and implantation.
The secretory phase, from days 15 through 28, leads to higher production of progesterone by a separate organ within the ovary (the corpus luteum), prompted by the estrogen-primed status of the uterus. Luteinizing hormone (LH) helps aid in the actual release of the mature egg. Progesterone is the hormone that helps to nourish the organs of both mother and baby in the event an embryo (fertilized egg) has been implanted in the lining of the uterus.
At the tail end of this phase, women who are not pregnant will experience cramping, bloating, mood swings and other premenstrual discomforts as the hormones respond by shifting to the infertility phase. The ovaries continue their careful chemistry balance and egg maturation, the lining of the uterus breaks down to be released in the flow described in the menstrual phase (above) and the cervix dries and firms up.
This description of the menstrual cycle more or less describes what happens throughout a female's lifespan between the age of puberty onset and menopause, unless they are pregnant. During pregnancy, the major rise in progesterone during that period of time can lead to all kinds of side effects: See our introduction to sleep during pregnancy here for more details.
At menopause, estrogen levels drop as there are fewer eggs to mature and release until, eventually, your cycles stop entirely. These changes in hormone levels lead to erratic changes in flow, mood swings, hot flashes, night sweats, sleep disturbances and vaginal pain during intercourse. Perimenopause marks the period of this transition in hormones, whereas menopause marks the point in which 12 months have passed without a menstrual cycle, which confirms the egg supply is empty.
But how does any of this relate to sleep?????
For those women, from menarche all the way to perimenopause, who are not pregnant, rapidly changing hormones on a monthly basis can still lead to pain, such as headache or cramping, that can disrupt sleep.
Pregnant women (see our 4-part series on Adventures in Sleep for the Pregnant Woman to learn more) can encounter a multitude of sleep problems that are related not only to the circumstances of pregnancy, but to raging hormones.
For women who are in perimenopause, side effects caused by changing hormone levels, like night sweats and mood swings, can also interrupt sleep. Dr. Sharon Wong of Adventist Medical Center in Portland quotes sleep studies that show that "women are more prone to having their sleep disturbed in the first half of the night by having a hot flash.” However, “[d]uring REM sleep, in the latter half of the night, women seemed to be more able to suppress their sleep disturbances.”
Fortunately, once menopause sets in, these side effects do subside.
What can a woman do about sleep problems that she suspects are related to hormonal changes? It's always a good idea to speak with your doctor first about your concerns. Sleep problems have multiple causes and root causes need to be ruled in or out. If your doctor determines your sleep issues are related to hormones, you will have to decide what therapy is right for you. There are drug therapies, herbal therapies, lifestyle changes and/or simply riding out the phase. Your therapy will reflect what is most important for you.
Ultimately, if hormones are messing with your sleep, one of the best things you can do for yourself is to practice excellent sleep hygiene and address any issues you may have with depression, mood swings or anxiety, which may be aggravating your sleep as well as the hormone shifts themselves.
Spectrum Health offers this informative Q&A Session with Dr. Diana Bitner, an OB-Gyn who has some good advice for dealing with sleep problems that could be the result of menstrual cycle issues.
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