Chart your temperature: That is, your basal body temperature, or BBT. Taken with a special thermometer (yes, you guessed it, a basal body thermometer), your BBT is the baseline reading you get first thing in the morning, after at least three to five hours of sleep and before you get out of bed, talk, or even sit up. Your BBT changes throughout your cycle as fluctuations in hormone levels occur. During the first half of your cycle, estrogen dominates. During the second half of your cycle (once ovulation has occurred), there is a surge in progesterone. Progesterone increases your body temperature as it gets your uterus ready for a fertilized, implantable egg. Which means that in the first half of the month, your temperature will be lower than it is in the second half of the month, after ovulation.
Get to know your cervix: Ovulation isn’t an entirely hidden process. As your body senses the hormone shifts that indicate an egg is about to be released from the ovary, it begins to ready itself for the incoming hordes of sperm and give the egg its best chance of getting fertilized. One detectable sign of oncoming ovulation is the position of the cervix itself. During the beginning of a cycle, your cervix — that neck-like passage between your vagina and uterus that has to stretch during birth to accommodate your baby’s head — is low, hard, and closed. But as ovulation approaches, it pulls back up, softens a bit, and opens just a little, to let the sperm through on their way to their target. Some women can easily feel these changes, while others have a tougher time. Check your cervix daily, using one or two fingers, and keep a chart of your observations. The other cervical sign you can watch for is the appearance, increase in quantity, and change in consistency of cervical mucus (the stuff that gets your underwear all sticky). Its more noble purpose is to carry the sperm to the ovum deep inside you.