IN JUNIOR-HIGH BIOLOGY ABOUT THIRTY years ago, I looked under the microscope my teacher offered and struggled to figure out how the stuff on the slide was relevant to me. I’d just begun to menstruate, and I wanted to know how my body worked. I wondered if other girls had strong cramps and what they did to ease them. I wondered if menstruating meant that if I had sex, I could get pregnant any day. Or was it just a few days each month? If it was just a few days, which days were they?
Once I became sexually active, I got a diaphragm and then a cervical cap. I asked a doctor and a midwife if they knew a way I could learn to tell when I was fertile. Each of them shook their heads.
Years later, my boyfriend and I drove toward a cabin out of town to celebrate my birthday. “I’ve got another yeast infection,” I said quietly.
“Well that’s lousy,” he said.
The lousiness wasn’t that I was sick, but that we wouldn’t be able to make love. Already that year I’d had several yeast infections because of irritation from the spermicide I used with my cervical cap.
How do I get out of here? I wondered. Out of feeling like my birthday celebration is only about sex, out of birth control that makes me sick?
Sex, fertility, love. Like the burning in my groin, they made a tangle too hot to touch.
Learning to Chart
Once I heard about Fertility Awareness (FA), also called Natural Family Planning (NFP), I decided to learn it. FA is based on a woman’s daily charting of her waking temperature and cervical fluid. With Fertility Awareness, a woman can tell when she’s fertile and infertile. To avoid pregnancy, couples postpone intercourse or use a barrier method on fertile days. To conceive, they know the best time to try.
Fertility Awareness is not the same as the (unreliable) Rhythm Method, which determines fertility by the patterns ofprevious cycles. FA gauges fertility as the woman’s daily chart evolves. According to numerous studies, when its rules are followed, Fertility Awareness is virtually as effective as the Pill.
Through books and classes about Fertility Awareness, I finally learned the vocabulary of my menstrual cycle, the functions of different hormones, and how to determine when I am fertile and infertile. As I started to observe and record my fertility signals, I began to experience explosions of awe: I had never conceived or tried to, but from charting I could see bona fide proof of my fertility. My cycles had often been erratic, and now (from knowing when I ovulated), I could predict when my period would come. I was with a new man while I learned the method, and his interest in the method helped both of us appreciate my femaleness.
Brooke, my partner, realized that ever since he was a teenager, he’d woken every morning and asked, When was the last time I had intercourse? And, Do I feel like masturbating? (Based on surveys of men who’ve taken my classes, this is a pretty typical way for a man to start his day.) Once I started charting, Brooke had a new waking question: Is Katie fertile? (Other men report wondering, What’s my partner’s temperature?) As awareness of fertility patterns emerged, my feminine rhythm gently took the lead in Brooke’s and my relating.
I began to see that the rhythm of masculine sexuality is essentially on all the time—essentially, men are fertile all the time. Meanwhile, because women are fertile, on average, only one-third of each cycle, feminine cycles seem to invite periodic rest from sexual intercourse.
Despite my feminist perspective, I came of age expecting that I should be available for sex all the time. I remember one three- or four-month period when I was physically able and wanting to have sex every day. Surely, I thought, my boyfriend and I would stay together if I could keep this up. Now, I wonder how my access to artificial birth control contributed to such thinking.
Indeed, sterilization, the Pill, Depo-Provera, the IUD, the diaphragm, the cervical cap, and condoms give women in heterosexual relationships the option of having fewer children than earlier generations. These methods allow choice about the course of our lives. However, artificial birth control is usually distributed without substantial information about how our bodies or the methods work.
I began to wonder what price we pay when we don’t know this basic information about ourselves.
Charting my fertility signals, I felt more connected to myself, and to other women who understood their own cycles. Taking my temperature and observing my cervical fluid felt like rituals for contacting a rhythm larger than my own. Brooke and I found ourselves supported by the rhythm my charts offered. Why hadn’t we learned this method before?
Trying to Become a Fertility Awareness Teacher
Because of my passion for the method, I began writing a story about its availability in northern New Mexico. One of the people I called was the director of a Natural Family Planning clinic at an Albuquerque hospital. When the woman said she would be offering a course to train people to teach the method, I asked for an application.
“I could send you one,” she said, “but I couldn’t accept you.”
I was stunned. “Why?” I asked.
“Because you’re single and you have genital contact.” If I was celibate or married, then her program could accept me.
This was spring 1997.
I wanted to understand this clinic’s policy, which is common among Catholic programs wherein medical information is taught effectively and woven with moral messages. I wanted to understand why Fertility Awareness isn’t more available, especially in secular communities. And I wanted the name of someone who could train me to teach the method. Indeed, the NFP clinic’s policy raised numerous questions and propelled me on to a tour of conversations. I spoke with the director of medical affairs for Planned Parenthood, nurse practitioners in women’s clinics, the medical journalist Nona Aguilar, and Suzannah Doyle, who wrote about the method for Our Bodies, Ourselves.
One of the first people I called was Kara Anderson, then Planned Parenthood’s director of medical affairs. She explained that their practitioners rarely have more than twenty minutes with each client. “Most of the people who come to us have been sexually active for six months—without any birth control,” Anderson said. “Our practitioners give each woman as much as they can.”
If a Planned Parenthood client asks to learn Fertility Awareness (which is unusual), she’s usually referred elsewhere—often to a teacher affiliated with a Catholic organization. “To learn this method well,” Anderson said, “a woman needs to be in close touch with a teacher for three or four months. In many areas, Catholic organizations provide the method’s only teachers. We simply don’t have staff or finances available to offer it on a large scale, given the limited number of women who request it.”
Anderson then succinctly articulated that Fertility Awareness can “enhance people’s self-awareness, self-esteem, and communication skills. And these are things we want for all women.”
I began to see that while learning Fertility Awareness is time intensive, once a woman owns a thermometer and knows the method, there’s nothing to purchase again. I began to wonder how classes could be administered for a wide variety of people from a range of backgrounds.
My next call was to Laurie Holmes, a certified nurse-midwife who often dispenses birth control. “I’ve seen too many unwanted pregnancies with Fertility Awareness to feel entirely comfortable endorsing it,” she said. “I bring it up, but people need time to learn it and stay with the daily charting. I think you need to be open to failure if you use it. I also find that people don’t want abstinence.”
I told Laurie, who, like most health-care practitioners, is not trained to use or teach FA, about the first woman I met who used it. She’d had two abortions by the time she was twenty-one, then vowed never again to have an unwanted pregnancy. After her second abortion, she chose FA for birth control; and 115 cycles later, she hadn’t conceived again.
This woman taught herself the method from reading a book; and, indeed, it took her several months before she felt confident enough to engage in sexual intercourse. Now, though, this woman says, “I know when I’m fertile, and when I’m not. Artificial birth control feels too risky to me.” After her abortions, learning how to read her cycles was a rite of passage.
Laurie Holmes found it exceptional that a woman would have the discipline to take her temperature every morning through her childbearing years.
I began to wonder if Fertility Awareness is not taught as well in the women’s community as it is among Catholics (certainly it’s less available) and how this might figure into practitioners’ lack of faith in the method and people’s capacity to commit to daily charting. Are the teaching methods, commitments, and self-control expressed in the Catholic community not available to others? Does the spiritual foundation that Catholic programs provide increase users’ efficacy with the method?
The Couple to Couple League (CCL), one of several Catholic organizations dedicated to teaching Natural Family Planning, has 22,000 subscribers to its newsletter, Family Foundations. Founded in 1971, the CCL is staffed primarily by volunteers who perceive teaching as service; and it’s therefore able to offer classes at a nominal fee. Indeed, the CCL is one of several groups that admirably meets the needs of practicing Catholics. Its publications include chart reviews, discussions of men’s involvement with charting, the effects of breast-feeding on fertility, descriptions of the effects of various drugs on fertility signals, what to expect when coming off the Pill—and numerous prescriptions for living a moral life.
Currently, over 700 volunteer couples teach NFP through the CCL. These teachers are required to sign a principle statement advocating, for example, marriage and breast-feeding, and rejecting abortion, premarital sex, and homosexual behavior. While I appreciate the CCL’s clear outlaying of their beliefs, their programs speak primarily to married, practicing Catholics who are open to the possibility of a child. Their literature is extensive (and available in Spanish); their teachers have been uniformly kind and generous—even while knowing I’m not Christian or married; and I often find beauty in their presentation of charting in a spiritual context. Alas, I’m not in concert with their basic tenet that there are a limited number of right and true ways to behave when it comes to sex and fertility. Learning Natural Family Planning through the CCL is not for everyone.
When I called Nona Aguilar, author of The New No-Pill, No-Risk Birth Control (Simon & Schuster, 1986), I described my frustration that I was not acceptable to the training program at the Albuquerque clinic. “Well,” she said, respectfully, “I agree with that policy.”
I leaned back in my chair. “Okay,” I said. “I don’t understand this. Please explain.”
“Properly used,” she began, “sex is about emotional and psychological union. In our culture, artificial birth control—which feminists have strongly advocated—has made sex a recreational activity. Sex certainly can be recreational, but its potential is to be transcendent. Sex is the life-bearing force of humankind. When lovemaking is recreational, it’s a little like being color-blind during sunset over the Grand Canyon. Union becomes harder to experience, and that’s a loss.”
With Natural Family Planning, Aguilar continued, “issues of control and communication—which naturally arise in a sexual relationship—are strongly brought to the fore. The method can help support that exploration.” And the container of marriage, she insisted, the commitment of marriage, supports the exploration.
Aguilar’s thoughts stirred me deeply and encouraged me to revere Fertility Awareness more than before. Our conversations also strengthened my desire for classes that teach people how our bodies work and that offer opportunity for individuals to differentiate between their personal values around sexual issues and the prohibitions suggested by society. Properly trained, I felt that I could teach such classes, despite my not being celibate, despite my never having felt moved to marry.
Finally, I called the Boston Women’s Health Book Collective. By then I doubted if I would ever meet someone who could or would train me to teach Fertility Awareness. I was given the number of Suzannah Doyle, who wrote about the method for the last several editions of Our Bodies, Ourselves.
Suzannah suggested that charting speaks to a tradition when women were in charge of their own health care. She impressed upon me that charts could be used to gauge gynecological health. She explained that Fertility Awareness teachers usually tell their clients that they have choices during their fertile phases: they can use barrier methods to prevent pregnancy, postpone intercourse, or enjoy sexual expression that doesn’t include genital-genital contact. (She prefers to suggest that couples who don’t want to conceive “postpone” intercourse—rather than abstain from it—during the woman’s fertile phase.) “In any case,” Doyle said, “since women are fertile only one third of their cycle, using birth control for two thirds of it—when a woman is naturally infertile—is a waste.”
Doyle also confirmed that most of the scientists who’ve done research in this field have been male Catholic MDs. Until the 1980s, Fertility Awareness was only available from a Catholic perspective; when Doyle began learning FA, she couldn’t have gotten the information she wanted from a women’s clinic, either. Since then, a small number of nonreligious teachers (who usually learned the method through Catholic organizations) have offered classes throughout North America.
Now, the Fertility Awareness community is often divided between those who are pro-choice and pro-life. “I call myself pre-choice,” Doyle said. “If people—including teenagers—know their fertility signals, they’re more likely to make informed, responsible choices about sex.” She also emphasized that each perspective serves a purpose and meets the needs of different populations.
Suzannah gave me the name of Wendy VanDilla, a colleague who could train me to teach Fertility Awareness. She also gave me her library on the subject, as she had moved on to a new career in music. I studied with Wendy, read voraciously, and attended a CCL workshop with Donna and Bill Taylor, internationally recognized authorities on lactational amenorrhea. I started teaching at the Santa Fe Community College, then began offering classes at Women’s Health Services (WHS), an MD-staffed clinic founded in 1972 in Santa Fe. WHS is one of only a few secular, not-for-profit clinics in the country that offers classes in Fertility Awareness.
Using Charts to Gauge Gynecological Health
Later in 1997, because of menstrual irregularities, I went to see Dagmar Ehling, DOM (doctor of Oriental medicine), the author of The Chinese Herbalist’s Handbook. I’d just begun teaching Fertility Awareness and brought my charts to her office. To my great joy, Dagmar could read them. In fact, she routinely requests that her women clients of childbearing age chart their waking temperatures. Dagmar had recently completed a postgraduate gynecology course for DOMs with Dr. Bob Flaws, who translates Chinese research (including studies on women’s waking temperatures) into English for Blue Poppy Press. Blue Poppy’s seminar had focused on using the waking temperature to gauge gynecological health; it did not include information about cervical fluid. Dagmar and I traded notes. We found ourselves eager for this information to be made available to health-care providers. In November 1999, we published “Gauging a Woman’s Health by Her Fertility Signals: An Introductory Synthesis of Western and Chinese Medical Principles” in the peer-reviewed journal Alternative Therapies.
By this time, the first edition of Toni Weschler’s groundbreaking book Taking Charge of Your Fertility had been published. Frequently referred to as the fertility bible, Toni’s book initiated the movement to reform women’s health by introducing Fertility Awareness to the mainstream. While many of my students were coming to class with charts that could not be found in textbooks, I found myself wanting clear guidelines—for women and health-care providers—about reading charts to gauge gynecological health. I wanted a repertoire of natural remedies for strengthening the menstrual cycle, and for women to hear each other’s experiences with charting. I wanted to offer more information about using FA while breast-feeding. This book, which I see as a companion to Toni’s, began to write itself.
Myths of Fertility
Thousands of years ago, women created the first calendars by marking the phases of the moon and their own menstrual cycles with tallies etched into objects like bison horns.1 In The Lunar Calendar, publisher Nancy Passmore writes, “The origins of a wholistic view of the world lie in these early observations: we are part of nature and nature is part of us.”
Julius Caesar outlawed lunar calendars in 45 B.C.; the Council of Constantinople declared the concept of cycles heretical in the fifth century A.D.2 Most calendars today largely ignore the lunar cycle. Some, such as the Jewish calendar, continue to be oriented to lunar and solar cycles.
I can’t help but wonder how, over time, decreased awareness of lunar cycles has affected our awareness of fertility’s cycles. So many people’s ideas about fertility have been flat-out wrong. In 1672, for example, a researcher named Kerkring theorized that women “eject ova above all during the menses, or on being vehemently angry.”3 Some people still mistakenly believe that a woman ovulates only when she has an orgasm, or that pre-ejaculate doesn’t contain enough sperm to cause a pregnancy. Our culture’s general lack of information about reproductive physiology, coupled with the lack of effective ways to prevent unintended pregnancies, has meant that a lot of women have had more children than they wanted or could sanely handle. More recently, some pharmaceutical companies have created drugs that make monthly bleeding “optional”; and some gynecologists have proclaimed that suppressing periods “gets women to a more natural state.”4 (Personally, I don’t see how suppressing menstruation is at all natural.) Meanwhile, many of us listen for the messages our bodies provide, and seek to live in concert with them.
A Short History of Fertility Awareness
In the 1920s, an Austrian surgeon and another in Japan simultaneously discovered that ovulation usually takes place fourteen days before the onset of the next period. With this discovery, the first scientific study in modern times of a natural system of family planning began. Called the Calendar or Rhythm Method and based on information from a woman’s past cycles, it helped women with predictable cycles to prevent pregnancy. Women with irregular cycles still had no way to determine when they were fertile.
In the 1960s, Drs. John and Evelyn Billings, Australian physicians, found that healthy women have a standard cervical mucus pattern that parallels hormonal changes. During a woman’s fertile phase, glands in the cervix secrete mucus, which can keep sperm alive for up to five days; at ovulation, this same fluid helps sperm travel toward a mature egg in a fallopian tube. During infertile days, the cervix’s dry secretions create a hostile environment for sperm to survive.
The Billingses realized that women could observe their mucus patterns and identify their own fertile and infertile times. They began offering workshops worldwide to teach the Ovulation Method to couples wanting a natural way to either avoid or achieve pregnancy. The Sympto-Thermal Method of Fertility Awareness was born when charts of cervical fluid were combined with charts of the waking temperature.
According to numerous studies, if its rules are followed, Fertility Awareness is as effective as the Pill in preventing pregnancy. The method has also helped countless couples to conceive, and it can be used to help gauge gynecological health.
Why isn’t Fertility Awareness widely known? Plenty of folks have heard of the Rhythm Method, and that it’s ineffective; many people confuse the two. Few health-care providers know about FA, while they do know about the Pill. And usually, those who teach Fertility Awareness are in touch with each other informally, without institutional support. As our society has become more health conscious and more interested in addressing our concerns (including reproductive concerns) without pharmaceuticals, Fertility Awareness has become more popular.
A Community of Charters
A short time after I began teaching Fertility Awareness to prevent or achieve pregnancy, the women in my classes started using their charts to conduct research on their own health. They observed how long it took to ovulate after they’d been on hormonal contraceptives. One woman charted her signals for nearly two months with an IUD (which she’d had inserted five years before) and then continued charting after it was removed. Others noticed how different diets affected their monthly cycles. None of these women are doctors, and yet their research gave me something I could share with new students in similar situations. As women continue charting and asking keen questions about their own health and health care, they come to understand their bodies and the ecosystems within which they live with increased strength and fullness.
From these women’s observations, I’ve come to understand how consumption of organic butter, my thyroid, hazardous waste in our oceans, my menstrual cramps, and my relationship with my partner are all connected!
I’m dreaming now: of adolescents knowing how their reproductive systems work before they become sexually active and before they choose a method for preventing pregnancy; of women and men being as aware of our fertility as we are of our sexuality; of Fertility Awareness classes as available as the Pill and fertility-enhancing drugs; of alliances between those who provide health-care education in women’s and Catholic communities; of alternative and allopathic medical students learning how to read fertility charts; of medical research on fertility signals; of every person intimately knowing the sacredness of their procreative powers.
A Note About Reading The Garden of Fertility
I CALL THE INFORMATION PRESENTED IN chapters 1 through 6 the core material of Fertility Awareness. I consider knowing it a basic life skill. Information presented in the other chapters is no less important, but understanding the core material is necessary to reap full benefit of these other aspects of Fertility Awareness.
Those who contemplate the beauty of the earth find reserves of strength that will endure as long as life lasts.
There is symbolic as well as actual beauty in the migration of the birds, the ebb and flow of the tides, the folded bud ready for the spring. There is something infinitely healing in the repeated refrains of nature—the assurance that dawn comes after night, and spring after the winter.
The Sense of Wonder, 1965
1. A Woman Is Like the Earth:
Reproductive Anatomy and Physiology
LIKE THE EARTH’S SURFACE, A WOMAN of childbearing age cycles through phases of cooling and heating, which in turn create moistening and drying, which in turn create a fertile environment for life to evolve. Rocks, glaciers, plants, and animals (including humans) all evolve in concert with these processes. In the same way that a meteorologist predicts weather by observing patterns of heating and cooling and moistening and drying at the earth’s surface, a woman of childbearing age can observe her body’s fertility signals and know whether or not she’s ovulating, when she’s fertile and infertile, if she’s prone to ovarian cysts or miscarriage, if she’s pregnant, and more.
The first step is learning reproductive anatomy (the parts of the body) and physiology (what the parts do).
The Female Reproductive System
The female reproductive system operates in a cyclical rhythm. Until puberty, a girl is not fertile. Once she begins to menstruate, she’s entered her childbearing years; and she’s potentially fertile until menopause, when reproduction is no longer possible. Unlike most species (female orca whales are another exception), human females can live for decades after their biological fertility has ended.
During the childbearing years, each menstrual cycle moves a woman through infertile, fertile, and again infertile phases. Like the earth’s seasons, women move through a dry-infertile phase, then a moist-fertile phase, and again a dry-infertile phase. To observe your own fertility, the first step is learning reproductive anatomy.
The uterus is a sterile muscle, about the size of a lemon and shaped like an upside-down pear. There are no bacteria in the uterus so that it can provide a hospitable environment for a baby. This lack of bacteria also renders it vulnerable to sexually transmitted infections. The neck of the uterus, the cervix, projects into the vaginal canal. The cervix’s opening is called the os. This is the area that’s swabbed during a pap smear to test for cervical cancer. Menstrual blood also passes through this opening. During childbirth, the os dilates ten centimeters.
The cervix is filled with glands, called crypts, which produce cervical fluid. Inside the crypts, cervical fluid can keep sperm alive for up to five days. I’ve known some Fertility Awareness teachers to call these recesses in the cervix “the sperm hotel.” Cervical fluid also filters out impaired sperm and provides a conduit for sperm to travel at ovulation from the cervix to the ripe egg in the fallopian tube.
On each side of the top of the uterus, there’s an ovary, a gland that contains follicles; follicles are unripe eggs held in sacs. By the time a female fetus is just four months old, she’s already made all of the follicles that she will ever produce. At birth, a baby girl’s ovaries hold about one million follicles. By the time menstruation begins, half of these follicles will have dissolved. By midlife, it becomes more difficult to stimulate a follicle to release an egg and for a released egg to be penetrated by sperm.
Fallopian tubes also extend from each side of the top of the uterus. Conception takes place in a fallopian tube, which also transports the fertilized egg to the uterus for pregnancy.
The vaginal canal stretches from the cervix to the lips of the vagina. The lips are also called the labia. When a woman is aroused, the walls of her vagina secrete arousal fluid, sort of like sweat, so that she is lubricated well and intercourse will not be painful.
Just above the vaginal opening, under a small hood where the labia join, is the clitoris. This small knob contains a woman’s most sensitive sexual nerves.
Figure 1.1. FEMALE REPRODUCTIVE ANATOMY
The Menstrual Cycle
To begin a menstrual cycle, the pituitary gland sends a hormonal message to the ovaries. Hormones are essentially messengers that travel through the blood to direct organs to carry out specific functions. The word hormone comes from the Greek words horme, which means “impulse,” and horman, which means “to urge on.”
Throughout the cycle, the pituitary gland secretes follicle-stimulating hormone (FSH), which encourages follicles in both ovaries to mature. During each cycle, about a dozen follicles are given the impulse to ripen. As they mature, these follicles produce estrogen.
While follicles are maturing and emitting estrogen, the woman is in her follicular phase. Also called the preovulatory phase, it typically begins a few days after menstruation and ends at ovulation. During this part of the cycle, estrogen is dominant.
Estrogen has several key functions:
- It stimulates the production of cervical fluid, which can keep sperm alive for up to five days.
- It cools the woman’s temperature. Likewise, when a man is maturing sperm—which happens to be all the timefrom puberty on—the testicles are a couple of degrees cooler than the rest of his body. This is why the testicles hang outside a man’s trunk, which is warmer. While we are maturing eggs and sperm, humans prefer a cooler temperature.
- It softens the cervix, raises its location in the vaginal canal, and opens the os—in order to receive sperm more readily.
- It builds a new endometrial lining in the uterus in preparation for a possible pregnancy.
- And, as the meaning of its Greek root, ois-tros, suggests, estrogen makes many women “mad with desire” at this phase in the cycle.
When one egg within a follicle reaches maturity (10 percent of the time, two eggs simultaneously reach maturity, which is how fraternal twins are conceived), rising estrogen levels signal the pituitary gland to send out luteinizing hormone (LH). LH causes the ripe egg to burst out of its follicle, and out of the ovary. The fimbria (the fallopian tube’s fingers) then reach out and grab the egg. This process is called ovulation (see figure 1.2). Even if two or more eggs are released, the hormonal sequence that results in ovulation occurs only once each cycle.
A ripe egg (about the size of the period at the end of this sentence) can live in the outer third of the fallopian tube for twelve to twenty-four hours. If there are sperm in the woman’s cervix or if the couple has intercourse while an egg is alive in a fallopian tube, the sperm will swim up through the uterus and the fallopian tube, where they will try to fertilize the egg. It is not known how sperm sense that a ripe egg is available, but they can reach it in as little as thirty minutes. Fertilizing the egg is called conception.
If there are no sperm present in the cervix, and if the woman has no unprotected sexual intercourse while the egg is alive, then the egg will simply dissolve.
It’s important to note that being fertile is not the same as ovulating. A woman is fertile when she has cervical fluid that can keep sperm alive; ovulation refers to the release of a mature egg and its twelve to twenty-four hour lifespan in a fallopian tube.
Before I describe what happens to a fertilized egg, let’s go back to the follicle, which is now an empty sac, still residing in the ovary.
After ovulation, the follicle changes its name and its job. Now it’s called the corpus luteum, and it emits the hormoneprogesterone. After ovulation, the menstrual cycle enters the luteal phase. Named for the corpus luteum, this postovulatory phase is dominated by progesterone.
When I hear “progesterone,” I think pro-gestation. This hormone has several functions:
- It dries up cervical fluid. If you do become pregnant, progesterone helps form a sticky “mucus plug” over your cervix to keep bacteria from entering the uterus. This keeps your baby’s environment sterile until birth.
- It warms your body temperature, because a fetus requires a slightly warmer temperature while it develops.
- It closes the os and hardens and lowers the cervix.
- It helps the new layer of your uterus become spongy, so that if you do conceive, the fertilized egg has bloody tissue in which to implant. If you don’t conceive, the blood and tissue are released at menstruation.
- It also helps facilitate easy menstruation and ease the transition to menopause.
Figure 1.2. RIPENING FOLLICLES AND OVULATION
Progesterone is activated after ovulation whether you conceive or not. Typically, the corpus luteum will live (and emit progesterone) for twelve to sixteen days. If you don’t become pregnant, the corpus luteum will die. As a result, your temperature will drop, and you won’t have enough progesterone to sustain your uterine lining: menstruation will begin within a day or two.
Once about two hundred sperm reach the fallopian tube, they begin a cooperative project of softening the egg’s enzymatic shell—so that one sperm can penetrate and fertilize the ripe egg.
If the egg is fertilized, cilia (whiplike cells that line the tube) take about five days to move the conceptus (the fertilized egg) down the tube to the uterus. Pregnancy occurs when the conceptus implants in the uterine lining (see figure 1.3).Human chorionic gonadotropin (HCG), the only hormone healthy men and women don’t have in common, is then secreted by the fertilized egg itself; HCG instructs your body to nourish the growing fetus. Urine tests for determining pregnancy look for the presence of HCG. If pregnancy does occur, the corpus luteum will continue to emit progesterone for three months; and then the placenta takes over progesterone production.
Figure 1.3. CONCEPTION AND PREGNANCY
Conception takes place in the outer third of a fallopian tube. Once the egg is fertilized, it takes about five days to travel down the tube. During these few days, the corpus luteum emits progesterone, which causes the endometrium to thicken with blood.Pregnancy occurs when the fertilized egg implants in the endometrium.
To learn what happens to the menstrual cycle when a woman is on the Pill, see here in chapter 7. Also, to see images of normal cycles and how the Pill affects them, www.fertilityawareness.net posts photographs of the cervixes of women who aren’t on the Pill, and one who is.
Figure 1.4. THE MENSTRUAL CYCLE
1. Menstruation begins when the corpus luteum dissolves and the previous cycle’s uterine lining is released.
2. Typically, after her period, a woman has a few days of lowered hormonal activity. No mucus is produced and temperatures are low.
3. The follicular phase. About a dozen follicles (sacs holding unripe eggs) are given the impulse to mature and emit estrogen, which causes production of cervical fluid. (CF can keep sperm alive for up to five days.) Estrogen also cools a woman’s basal temperature and signals the cervix to open, soften, and rise in the vaginal canal. It also signals the uterus to build a new, bloody lining. The follicular phase typically lasts seven to ten days. In some conditions, it can last for months or years.
4. Luteinizing hormone (LH), secreted by the pituitary gland, causes a ripe egg to burst from its follicle and the ovary. This is ovulation. Mucus may be very slippery at ovulation, or it may already have begun to dry up. The ripe egg will live in the tube for twelve to twenty-four hours.
5. The luteal phase. Here the corpus luteum emits progesterone, which makes the endometrium spongy, in case conception has occurred. (A spongy uterine lining is required for implantation—pregnancy—to be successful.) Progesterone also causes mucus to dry up; the temperature to warm up; and the cervix to close, become firm, and lower in the vaginal canal. If, after twelve to sixteen days, pregnancy has not occurred, the corpus luteum dissolves and a new cycle begins.
The Male Reproductive System
At puberty, the pituitary gland sends a hormonal message to a boy’s testicles (male reproductive glands, which are protected inside a sac called the scrotum) to begin producing testosterone. With the activation of this hormone, the larynx becomes longer and the voice deepens; facial and body hair appear; the shoulders become broader; and production of sperm begins. Starting in adolescence, in the testicles’ seminiferous tubules, a healthy man produces one thousand sperm per second—twenty-four hours a day, seven days a week. (As my grandmother would have said, this explains a lot of things.)
Men tend to produce more sperm during the winter, because sperm prefer a cooler temperature while they’re maturing. It therefore follows that a man who bikes in tight shorts to the hot tub every day throughout the summer after work baking pizza might find himself with a low sperm count!
While sperm production and the ability to cause a pregnancy can continue until a man dies, age and decreased testosterone levels typically cause sperm production and the ability to have an erection to decrease. Also, because of environmental toxins, sperm counts are now decreasing at an alarming rate of 2 percent per year in men of all ages. But essentially, beginning at puberty, men are fertile all the time.
Once they’re produced, sperm are matured and stored in the epididymis, a duct that is also held in the scrotum. The maturation process takes about two months: sperm produced at the beginning of January wouldn’t be ejaculated until the beginning of March. Just before orgasm, sperm move from the testicles through the vas deferens, tubes that carry sperm to the urethra. Fluid is collected from the prostate gland, the Cowper’s glands, and the seminal vesicles and then mixes with the sperm to create semen, which is then ejaculated through the urethra. Semen is chemically similar to cervical fluid, and it also provides nourishment to help keep sperm alive (see figure 1.5).
In a healthy man, each ejaculation contains between 250 and 350 million sperm. Typically, it takes thirty-six hours to replenish a man’s sperm count.
With a vasectomy, the vas deferens are cut to prevent sperm from being ejaculated. Sperm are still produced and matured after a vasectomy, but they’re prevented from being released through the penis. If a man has had a vasectomy, the amount of his ejaculate will still look the same: even 350 million sperm are not discernible to the naked eye.
Sperm are measured by their numbers, their ability to swim (motility), and their shape (morphology). If a man has a low sperm count, he should have it tested again a few weeks later, because sperm counts can fluctuate significantly in a short period of time.