Cervical mucus—that sticky, slippery, or watery clear fluid that comes out of your vagina— varies during your menstrual cycle and can tell you many things about your body. Vaginal discharge is also a not-often-discussed symptom of pregnancy, and you might be wondering whether cervical mucus or vaginal discharge can serve as an early clue that you are pregnant. What follows is a discussion of what your cervical mucus means, both before and after conception.
Cervical Mucus Before Conception
If you are trying to conceive, you have probably seen discussions of cervical mucus—often abbreviated “CM” online. Tracking the consistency, color, and amount of cervical mucus, which is also sometimes called cervical fluid, can predict your most fertile times, and some women regularly do so in order time sexual intercourse for conception or to avoid conceiving.  Here is an overview of the changes to cervical mucus during your menstrual cycle:
- During your period, any cervical fluid will likely be masked by blood flow.
- Just after your period ends, you will probably have minimal to no cervical mucus for a period of several days.
- When an egg begins to ripen, in preparation for being released, your cervix prepares by starting to make mucus, which will be scant and sticky at first. This early cervical mucus can be white, cloudy, or light yellow.
- In the days just before ovulation, the amount of cervical mucus increases as it becomes clearer and more watery and then slippery, like the white of an egg. The day with the most slippery cervical mucus is the day you are most fertile and a great day for sexual intercourse if you are trying to conceive.
- After ovulation, cervical mucus will likely become sticky and perhaps cloudy again for a few days before drying up in advance of menstrual bleeding. 
It is possible that what you have noticed about your body is consistent with the general summary above; however, everyone’s body is slightly different, so your cervical mucus may vary a bit. If you pay attention to your cervical mucus over the course of a few menstrual cycles, you will probably get a good idea of how your own body works. You can check your cervical mucus by reaching into your vaginal with a clean finger or by noticing how any cervical mucus looks on toilet paper when you wipe after going to the bathroom. 
Cervical Mucus and Vaginal Discharge After Conception
If you are trying to get pregnant, especially if you have been tracking cervical mucus, you probably hope that your cervical mucus can give you an early signal that you have successfully conceived. Unfortunately, any change to cervical mucus before you have taken a positive pregnancy test is probably not an early pregnancy sign. Even if you do see an increase in cervical mucus, it could just mean that your period is on its way. Just as blood flow to the reproductive organs increases before ovulation, increasing cervical mucus along with it, blood flow can also ramp up just before your period starts. The other thing to look for is brownish tinged vaginal discharge, which could be a sign of implantation, a positive pregnancy sign, or could just be spotting in advance of your period. 
Though cervical mucus does not necessarily tell you if you are pregnant in the early days after ovulation and before your missed period—the infamous two-week wait—it has an important role to play when you do become pregnant. The first job of cervical mucus is to contribute to your mucus plug, which seals the opening of your cervix and prevents germs from getting to baby.  A report published in the Australian and New Zealand Journal of Obstetrics and Gynaecology in 2005 suggested that fetal cells isolated from the cervical mucus in early pregnancy could correctly indicate the sex of the developing fetus. 
As your pregnancy progresses, another type of vaginal discharge called leukorrhea or leucorrhea increases due to blood flow to your reproductive organs and developing baby. Leukorrhea should be clear or slightly milky and odorless, and you might notice it in your underwear as a dampness that comes and goes or stays constant. Panty liners can help with dampness, which is completely normal. If your vaginal discharge starts to smell or itch, talk to your care provider in case you have an infection. Vaginal discharge usually starts around week eight of pregnancy, not early enough to indicate a pregnancy before you have missed a period and can take a test. 
- American College of Obstetricians and Gynecologists, Fertility Awareness-Based Methods of Family Planning
- Planned Parenthood, What’s the cervical mucus method of FAMs?
- Verywell Family, Can You Tell If You’re Pregnant By Checking Cervical Mucus?
- D. Mantzaris et al., “Preliminary report: Correct diagnosis of sex in fetal cells isolated from cervical mucus during early pregnancy,” Australian and New Zealand Journal of Obstetrics and Gynaecology, 2005.
- Verywell Family, What is Leukorrhea in Pregnancy?