Getting Pregnant Naturally_ Healthy Choi - Winifred Conkling [37]
WHAT IS “NORMAL” ANYWAY?
It only takes a single sperm to fertilize an egg, but millions of the little swimmers are present in the ejaculate of fertile men. A normal sperm count includes at least 20 million sperm cells per milliliter of ejaculate, or approximately 150 million to 200 million per ejaculation.
Typically, at least half those sperm are “motile,” or moving forward, rather than swimming in circles. And at least 40 to 50 percent should be normally shaped. Ideally you want to have both quality and quantity when it comes to sperm, but to protect your fertility, it is better to have fewer high-quality sperm than an abundant supply of sub-par sperm.
COUPLES
Try to Reach—and Maintain—a Reasonable Weight
You may not need another reason to worry about your weight, but evidence suggests that being too fat—or too thin—can affect your fertility. In men, being overweight can cause fertility problems because the testicles become surrounded by fatty tissue, making testicular temperatures rise and sperm counts drop. In women, too much or too little body fat can affect hormone levels and interfere with ovulation.
Women’s bodies are particularly susceptible to weight-related fertility problems because women’s fat cells are like tiny estrogen manufacturing plants. While some estrogen is produced in the ovaries, 30 percent of the body’s supply—and 80 percent during certain points of your menstrual cycle—comes from the fat cells. The typical body fat for a fertile woman is 29 percent; a woman’s hormonal system can shut down and she can become infertile if her body fat is more than 10 to 15 percent above or below normal. One study of 276 infertile women with ovulatory dysfunction found that 6 percent of the women had problems because they were overweight, and 6 percent because they were underweight.
Underweight women are often undernourished and have borderline vitamin and mineral deficiencies. Ultra-thin women often stop having their periods. Also, women who lose 10 to 15 percent of their total body weight (or one-third of their body fat) may stop having periods temporarily. Fortunately, weight gain often helps these women regain their fertility: One study of twenty-nine infertile women (each no more than 91 percent of her ideal body weight) found that those who were able to reach 95 to 100 percent of their ideal weight regained normal ovulation. Within one to three years, twenty-four of twenty-six of these now normal-weight women had become pregnant. Ideally, underweight women who have suffered from amenorrhea (absence of periods) should follow a balanced diet for three or four months after they resume menstruating before they try to conceive.
On the opposite end of the scale, obese women (those more than 20 percent above their ideal weight) produce too much estrogen, which then strains the liver as it tries to break down the excess levels of hormone. The high levels of estrogen also disrupt the hormone system that tells the egg follicle to mature. In fact, oral contraceptive pills take advantage of this hormone response by creating an artificial hormone imbalance. Obese women require higher doses of hormones to induce ovulation than their lean counterparts.
So, how much should you weigh? Your bathroom scale can tell you how much or how little you weigh, but not how fat you are. To assess your body fat, you can calculate your body mass index, or BMI. While bone structure and muscle development can influence accuracy, this method tends to be more reliable than a weight table, and it is accurate enough to give you an idea of whether you have a weight problem that may interfere with conception. Use the following formula:
For example, for a five-foot, seven-inch woman (sixty-seven inches) weighing 135 pounds, the formula would be:
If your BMI is 19 or less, you are underweight and may need to gain weight to enhance your fertility.
If your BMI is 20 to 25, you are within your healthy weight range and your weight should not cause a fertility problem.