Julie Medical Advisor
Conception 101: When does it happen?
“Conception" gets thrown around a lot when it comes to pregnancy, but it has a very specific meaning in the medical world. Conception is also known as fertilization. But even if conception (or fertilization) occurs, it doesn't automatically mean that you're pregnant. It’s just one part of the multi-step process of becoming pregnant, which starts with ovulation and ejaculation and then concludes with a successful implantation.
Read on to learn what conception is, the additional steps that lead to pregnancy, and when to take a pregnancy test.
What is conception?
In medicine, conception is the term used to describe the merging of the egg and sperm in the fallopian tube. It’s also known as fertilization. In order for this to happen, an egg has to be released from an ovary during ovulation and sperm must travel through the vagina and uterus.
After conception, the now-fertilized egg (called an embryo) must successfully implant in the uterus for a pregnancy to begin. However, there are a variety of reasons why implantation does not happen, and the embryo will pass out of the uterus on its own. About 50% of embryos don’t implant in the uterus. It’s also possible for the embryo to briefly attach and then detach shortly thereafter, something called a chemical pregnancy. This may look like a slightly delayed period with a little more bleeding than normal.
How does a pregnancy start?
Pregnancy begins when the embryo, which is formed when the sperm fertilizes the egg, successfully implants in the uterus and then continues to grow and develop.
Timing is everything when it comes to pregnancy. Here's the breakdown of the steps that are essential for a pregnancy to happen:
Ovulation takes place in between your periods and refers to the process where a mature egg is released from the ovary into the fallopian tube. Once released, the egg can survive for 24 hours.
If you have a 28-day cycle, ovulation generally occurs around day 14. But every woman's cycle is different, and the exact day of ovulation can differ for any number of reasons.
If you track your menstrual cycle, you may have a rough estimate of what days you're ovulating. There are some symptoms that can help you tell if you’re ovulating, such as cramping, changes in body temperature, or cervical mucus.
Fact: For conception to happen, ovulation needs to occur.
Fertilization is the fusion of an egg and sperm within the fallopian tube.
Following ovulation, an egg travels to the fallopian tube. An egg is capable of fertilization for only 12 to 24 hours after ovulation, so the presence of sperm is essential for fusion to happen there. Sperm reaches the fallopian tube by traveling through the vagina and cervix into the uterus and, finally, into the fallopian tube. Each single ejaculation contains millions of sperm, and it only takes minutes for the sperm to travel from the vagina to the fallopian tube.
Implantation is when the embryo attaches to the uterus. This usually happens about 7 days after fertilization. At this point the cells of the embryo have divided (through a process called mitosis).
When does implantation occur
Implantation happens about 7 days after fertilization.
Pregnancy timeline based on a 28-day menstrual cycle
Since it's difficult to know when you're ovulating, the cycle is based on a more obvious signal: the start of your period. The timeline begins on the first day of your period and ends on the day before the start of your next period. Ovulation occurs around the midpoint between your two periods.
Here's an example of what it might look like if you were to estimate the conception and pregnancy process on a 28-day cycle:
Day 1: First day of your period (AKA, you’re bleeding)
Around day 14: This is where ovulation occurs, and an egg is released. Usually, in the middle of the cycle.
Within 24 hours of ovulation: Conception may occur if sperm is present and fertilizes an egg. This creates an embryo.
About 5-6 days after conception/fertilization: Once the embryo has reached the blastocyst stage, it may attach to the uterine lining.
When to take a pregnancy test
At-home pregnancy tests work by detecting a hormone present in your urine known as human chorionic gonadotropin (hCG). Also known as the "pregnancy hormone," hCG levels increase after the embryo has implanted onto the uterus.
Home tests differ in how early they can detect a pregnancy. Some tests can detect a pregnancy 10 days after conception. If taken too early, it may show an incorrect result. For a more accurate result, wait to take the test until you notice your period is late or missed.
What if I don't want to get pregnant?
If you have sex regularly and don't want to get pregnant, use a regular form of birth control like the daily pill, IUD, ring, shot, implant, or patch. Barrier methods can also help prevent pregnancy, and they have the added benefit of helping to protect you from giving or contracting STIs.
If you had unprotected sex and want to prevent conception and pregnancy, use emergency contraception, like the morning-after pill, as soon as possible. Julie (levonorgestrel) tablets 1.5 mg and other morning-after pills can help prevent pregnancy up to 72 hours (3 days) after unprotected sex, but they’re most effective the sooner you take them. Morning-after pills are available at Walmart, Target, and retail pharmacies like CVS and Walgreens. They're legal in all 50 states and FDA-approved. No prescription, credit card, or ID is required for purchase.
Although the information above may be useful, it shouldn’t replace the advice of your healthcare professional. For questions about birth control and other women’s health issues, please talk to your healthcare professional.
Emergency contraceptives like Julie work when you take them after sex. That’s because emergency contraception prevents pregnancy by delaying when you ovulate. By taking emergency contraception before sex, you may not be delaying ovulation long enough.
No. Julie is not what is commonly called “the abortion pill” or “medication abortion”. The active ingredient in the abortion pill is mifepristone. Pregnancy needs a hormone called progesterone to grow normally. Mifepristone blocks your body’s own progesterone, stopping the pregnancy from growing. Julie does not and will not impact an existing pregnancy, and works by delaying ovulation before there is a pregnancy.
The FDA recently made an update in December 2022 to remove any language suggesting that Julie may prevent implantation of a fertilized egg. We are currently working on removing this outdated disclaimer but you may still see it present on some of our packaging in the meantime. Please disregard these statements because they are out of date. Julie will not impact an existing pregnancy.
Julie is an emergency contraception you can take after:
- You didn’t use any form of birth control or had unprotected sex
- There was an issue with your regular birth control method (eg, the condom broke or slipped)
- You missed a dose (or more) of your regular birth control pill
Taking Julie will not impact your ability to get pregnant.
After taking Julie you can continue on with your regular birth control method if you have one (for example, continue taking birth control pills).
You will know Julie has been effective when you get your next period, which should come at the expected time, or within a week of the expected time. If your period is delayed beyond 1 week, it is possible you may be pregnant. You should get a pregnancy test and follow up with your healthcare professional.
Julie is a backup or emergency method and should not be used as a regular birth control method. Consult with your doctor about a birth control method that makes sense for you.
Please know that taking a dose of Julie will only protect you from one instance of unprotected sex, it will not prevent pregnancy from unprotected sex over the coming days or weeks. If you have unprotected sex in the future and want to prevent pregnancy, be sure to take a new dose of Julie and talk to your doctor about the best birth control options for you.
Your menstrual bleeding patterns may change temporarily after using levonorgestrel. If you find that your period is more than a week late, take a pregnancy test to confirm whether the contraceptive has worked.
Julie can be used by all women, regardless of weight but women with BMIs above 29.9 have a pregnancy risk of 5.8% - meaning that out of every 100 women who take Julie, 6 may become pregnant. We advise that you speak with your doctor for further information on how this may affect you personally.
Take Julie tablets orally (swallow it). It is preferable to take it with water, and you can take it with or without food. Do not insert Julie vaginally.
Julie is not an abortion pill and will not harm an existing pregnancy nor will it be effective if a woman is already pregnant.
Julie is a progestin‑only emergency contraception product that helps prevent pregnancy before it starts when taken within 72 hours after unprotected sex.
Julie is a backup method of preventing pregnancy and should not be used as regular birth control. Use as directed.
Julie is effective up to 72 hours (3 days) after unprotected sex. The sooner it’s taken after unprotected sex, the better it works.
Julie can significantly decrease your chances of getting pregnant. When used as directed, about 7 out of every 8 women who could have gotten pregnant will not become pregnant after taking Julie. The most important factor affecting how well Julie works is how quickly it is taken. When taken as directed within 72 hours after unprotected sex or birth control failure, Julie can significantly decrease the chance that a woman will get pregnant. In fact, the earlier Julie is taken after unprotected intercourse, the better it works.
Emergency contraception is not 100% effective, which is why it is critical that women have a regular birth control method. If you have any further questions, we encourage you to talk to your healthcare provider.
Since emergency contraception can affect the length of your menstrual cycle, your period might come about a week later or earlier than usual after taking Julie. If your period is more than one week late, consider the possibility of pregnancy.
No. No one needs a prescription to purchase Julie or EC. However, some insurances require a prescription for reimbursement. Some pharmacies and places where EC is sold may tell you that you need a prescription. You do not.
You do not need to see a doctor before or after taking Julie. You do not need a prescription from a doctor. We do encourage you to speak to a doctor you feel comfortable with about sex, reproductive health, and contraception.
No. We know this is a common misconception so let’s break it down. Using Julie (no matter how many times you take it) does not affect your fertility — and it will not prevent you from becoming pregnant in the future. You should feel free to use Julie whenever you think it’s necessary. Julie (and all EC) is not recommended as an ongoing form of birth control because it’s not as effective at preventing pregnancy as birth control methods like the IUD, patch, pill, ring, or shot. Also, frequent use of EC may cause periods to become irregular and unpredictable. That’s it!
Yes. You are not alone. Often times, people who buy EC are feeling stressed out, concerned, embarrassed, confused or ashamed. The important thing to remember is that you are not alone, you have nothing to be ashamed about, and the Julie community is here to support you. By taking Julie after unprotected sex, you are taking control of your future and taking a safe, effective, approved method of preventing pregnancy.