How many kids could we have? (Or, "Why I'm impressed with the Duggers")

In my last post I mentioned that NaturalGuy and I have a great deal of confidence that we couldn't have 20 kids if we tried. I thought I'd share our math.

We're young - 23. The average age women reach menopause, defined as a full year without menstruation, is 51, and almost all women reach menopause by 55. It's worth noting that fertility declines significantly before this. But, let's be generous and assume I'll have 30 fertile years.

Review of "Moody Bitches: The Truth About the Drugs You're Taking, The Sleep You're Missing, The Sex You're Not Having, and What's Really Making You Crazy"

Interesting Video and Book Recommendation

I watched this and thought it was so interesting. It seems that a lot of my friends use hormonal birth control for similar reasons - for more stable moods, etc. I'll have to see if I can get a library copy of the book.

Does previous use of hormonal contraception affect future fertility?

Hormonal contraception obviously effects a woman's fertility while she is taking it (otherwise it wouldn't be a contraceptive!). When women discontinue taking hormonal contraceptives, often after years of taking them, they notice differences in their menstrual cycles. But it's hard for an individual to know if those changes are a result of the medication, or of age and lifestyle changes that occurred during the years of contraceptive use.

After discontinuing hormonal contraceptives, a non-trivial number of women find that it takes many months to return to a normal cycle, delaying pregnancy achievement. 

The Follicular Phase

The follicular phase is the time before ovulation. A few days before a woman gets her period, follicle-stimulating hormone (FSH) levels begin to rise. This leads several ovarian follicles to begin to mature. These follicles compete to produce the one egg that is released. As the follicles mature, they release estrogen. Following menstruation, rising estrogen levels stimulate the lining of the uterus to develop. The high estrogen levels lower basal temperature slightly and leads to fertile mucus.

The follicular phase varies in length, and is sensitive to disruption. Stress, illness, poor nutrition, etc can lengthen the follicular phase, delaying ovulation.

The Luteal Phase

How big is that baby?

An interesting overview of how babies develop here.

What is "women's health"?

It's not just reproductive health anymore!

Chart galleries

Recently, I've been looking at a variety of charts posted on the "Taking Charge of Your Fertility" site. The charts are tagged with characteristics (ie. "long cycle", "PCOS charts", etc.). It's very interesting to take a look at charts and see which are most similar to mine.

How does age affect pregnancy?

For women, age heavily influences fertility. Women are born with all the eggs they will ever have. Over the years, eggs decay in a process called "artresia." This decay occurs even in the healthiest women and is not prevented by birth control or infertility treatments - it is simply the result of age.

As a result of this natural decay of eggs, as women approach their mid to late 30's, they are more likely to have children affected by chromosomal abnormalities (the most common being Down syndrome). The "American Family Physician" article on Down syndrome provides the following graph showing the risk of Down syndrome as a % versus maternal age. As the article notes, from age 20 to 30, the risk of Down syndrome stays relatively stable, although it does increase somewhat. After age 30, the risk increases exponentially each year.

Additionally, women in their mid to late 30's are more likely to have miscarriages. The "Advanced Fertility Center of Chicago" provides the following summary of miscarriage rate by age group:

Maternal age	Pregnancy loss rate
< 30	8%
30-34	12%
35-37	16%
38-39	22%
40-41	33%
42-43	45%
44-46	60%

It is important to note that these rates of miscarriage only apply to pregnancies that have been confirmed by ultrasound, so the actual rate, including pregnancies lost very early on, would be higher.

To see this information interactively, check out the Age and Fertility Calculator.

How does fertility change around ovulation?

Couples seeking to avoid or achieve pregnancy often wonder how likely pregnancy is under a variety of circumstances. Understanding how to risk of pregnancy changes is a key part of natural family planning. Even within the "fertile window" which NFP identifies, the chances of pregnancy vary.

Health Benefits of Charting

Natural family planning is very education, even if family planning is the furthest thing from your mind! Toni Morrison, author of Taking Charge of Your Fertility, 10th Anniversary Edition: The Definitive Guide to Natural Birth Control, Pregnancy Achievement, and Reproductive Health, advocates teaching the observational methods of NFP/FAM to young women, in order to empower women to advocate for their health. (She's written a book for middle school and high school girls, Cycle Savvy: The Smart Teen's Guide to the Mysteries of Her Body, which teaches girls to observe the menstrual cycle, but avoids discussion of family planning).

Here's some of the ways charting can help you and your doctor:

1. You will have a great idea of what healthy cervical fluid looks like, and you'll have a much easier time identifying when discharge is unusual or a symptom of an infection.
2. You will be able to identify changes in how heavy or long your period is. Without written records, it can be very difficult to see trends, or to associate those trends with other changes. It's very interesting to see how heavyness/length is effected by medication, weight loss or gain, or dramatic dietary changes.

Hormone confusion: the biology behind stopping the pill

What happens when a woman stops taking hormonal contraception? We've talked about how hormones are effected by hormonal contraception and how hormones regulate the menstrual cycle, but what happens in between?

For the first week after a woman stops taking the combination pill, progesterone and estrogen drop, similar to how they drop during the withdrawal bleeding that occurs during the sugar pill days at the end of the active pills. During the subsequent weeks, as progesterone is no longer artificially increased by the combination pill, FSH and LH restart the natural ovulation cycle.

Some women find that it takes several months to get their period after stopping hormonal contraception. The hormones supplied by the pill leave the body very quickly, but differences between how quickly they leave individual women's bodies may explain short delays. Longer delays can be explained by the body taking time to begin producing normal levels of progesterone and estrogen on its own again. (Levels of estrogen and progesterone are regulated by "negative feedback loops," which means that when they were being supplied by the pill, the body produced less of these two hormones. It takes time for the body to rev back up into production.) Because we can't predict how quickly ovulation will occur after stopping hormonal birth control, it is important to treat this transition time carefully. Even after getting the first post-pill period, it may take several more cycles before the menstrual cycle is regular. In general, women are advised to talk to their doctor if they do not get their period within three months of stopping the pill.

Of particular concern to sexually active women who are discontinuing the pill and starting to use NFP, the transition period is a time when cervical mucus, cervix characteristics, and even temperature may be less reliable. This makes it hard to predict what times are fertile. "The Art of Natural Family Planning," published by the Couple to Couple League, offers special instructions  for this situation. "Taking Charge of Your Fertility," a secular approach to the sympto-thermal method, advises abstaining from intercourse or using barrier methods for the first three cycles after stopping hormonal contraceptives.

NFP and being sick

I've had a terrible cold the past week, so I thought a post about how being sick effects charting would be interesting.

Many women notice that sometimes stress or illness leads to getting their period late. You can generally tell whether your period will be delayed based on when you get sick. If you haven't ovulated yet, getting sick or stressed may delay ovulation, and as a result, your period may be late. If you have ovulated, your period will be right on time (provided you aren't pregnant!). The luteal phase, the time between ovulation and your next period, is a very consistent length and isn't interrupted by minor illness.

Putting it all together

In earlier posts I described three of the main signs of fertility

• temperature
• cervical fluid
• cervix changes

Today I want to talk a little bit about putting these together. The general rule if you want to avoid getting pregnant is to avoid intercourse unless all three signs indicate that you are not fertile.

Interpreting cervix changes

Cervix changes are a valuable source of information about fertility. Many women, however, feel uncomfortable checking the cervix.  The good news is that it's an optional sign. Even if it's a sign you want to track, you don't need to track it the entire month. You can use it to cross-check the other signs around ovulation.

The cervix sits several inches inside the vagina and separates the vagina from the uterus. 

From WebMD

Interpreting cervical fluid

Interpreting cervical fluid is less objective, but you'll quickly become an expert on your own body. During the day, pay attention to any discharge. This doesn't need to be too involved - generally it's enough to pay attention to any discharge on your panties and while wiping. At the end of the day, note any observations on your chart.

Because evaluating cervical fluid is less objective, every NFP method uses slightly different descriptions. In the Couple to Couple League's method, cervical fluid is described by three categories:

• No observed cervical fluid - There's no observable fluid
• "Less fertile" cervical fluid - Fluid is often white or creamy. It doesn't stretch easily and may be sticky, gummy, thick, pasty, creamy, or clumpy.
• "More fertile" cervical fluid - Fluid is wet and very slippery. There are often mucus pieces that are extremely stretchy. It's often described as being similar to raw egg whites.

This slideshow gives a reasonable description of different types of cervical fluid, and includes photos which may help you decide what you're looking at.

Hormones disrupted: the biology behind the pill

The menstrual cycle: the biology behind NFP

The Menstrual Cycle

The menstrual cycle starts on the first day the woman gets her period. In the first few days of the cycle, the hormone FSH rises, stimulating the ovarian follicles.

As estrogen increases, a woman notices more cervical fluid, starting with "less fertile" fluid that is sticky and gradually turning into "more fertile" fluid that is stretchy and wet. This gives the woman and her husband warning that she is approaching her fertile time frame. Since the couple cannot calculate exactly when to expect ovulation, the couple decides when to abstain based on cervical fluid and data from past cycles.