Charting a Course for Pregnancy
Ovulation and pregnancy go hand in hand. When pregnancy doesn’t happen as quickly as once thought it can be helpful to understand the ovulation process.
“Every woman’s fertility cycle is unique,” said Scott Bergstedt, MD, ob/gyn with OBG-1 of West Calcasieu Cameron Hospital. “Becoming aware of a woman’s particular fertility cycle is the first step in planning a pregnancy.”
Conception usually occurs during ovulation, or the one to two days prior to it. “There’s a surprisingly small window of opportunity for conception,” explained Bergstedt. “The newly released egg is fertile for twelve to twenty-four hours. For women who are having trouble getting pregnant, timing is crucial and knowing her individual cycle routine will help.”
Some women have ovulation pains which occur before, during, or after the ovulation period in the menstrual cycle. The pain is usually centered in the lower right abdomen, and may last anywhere from a few hours to days. “Although these pains can help alert women to the occurrence of ovulation, it’s not a strong enough signal to rely on independently. I advise my patients to use ovulation pains as a secondary fertility signal, that, taken with other ovulation symptoms, can help identify the time of ovulation,” he explained.
Basal body temperature, or BBT, is another method of detecting ovulation. “The basal body temperature is the body’s temperature at rest,” explained Bergstedt. “When the ovary releases an egg, it also releases the warmth-inducing hormone progesterone. This additional progesterone makes the body temperature rise about two-tenths of a degree within one to two days after ovulation.” The actual temperatures are not important, just the pattern of fluctuation. “Charting BBT helps the couple understand the physiological processes surrounding ovulation,” he said.
Because the temperature increase is so minute, within tenths of degrees, there are special BBT thermometers that measure the small increments. Temperature should be taken before getting out of bed. During the first two weeks of a menstrual cycle, the BBT is lower due to the presence of estrogen. “A typical range is from about 97.0 degrees to 97.5 degrees,” said Dr. Bergstedt. Immediately following ovulation, progesterone causes the temperature to increase by about 0.4 to 0.6 degrees until the time of the next menstrual period. This temperature rise indicates that ovulation has occurred.
BBT is affected by drinking alcohol and smoking. “These behaviors should be stopped prior to conception, anyway,” Bergstedt advised.
For more advanced techniques, there are ovulation predictor kits available for use at home. They are used during the middle of a cycle, around ovulation time, to determine exactly when it is occurring. These kits measure the level of luteinizing hormone in urine. “About 36 hours before ovulation, a spike in this hormone occurs, giving a good signal on the best time for intercourse,” Bergstedt said.
Using a combination of ovulation testing methods or products is the best way to get a comprehensive view of fertility. Most ob/gyn’s recommend waiting at least a year for pregnancy to occur before pursuing more in-depth fertility treatment. “On average, a couple having regular, unprotected sex has only a 20% to 25% chance each month of getting pregnant,” Bergstedt noted. “When a pregnancy isn’t desired, those are high percentages, but when a couple is trying to conceive, the view changes. On average, it takes half of all couples more than six months to conceive,” he said.