Conception to Implantation: What Happens?

Remember the sexual education classes you had to sit through in school? Was it exceptionally detailed? Or did you miss out on most of it from cringing in embarrassment? It’s time to go back in time to those classes and look at what you know about pregnancy from conception to implantation.

What is pregnancy, anyway?

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Pregnancy refers to the process that begins with ovulation, which then progresses to fertilization, and which is established when implantation takes place. During pregnancy, the fetus grows in the uterus, continues to grow, and pregnancy finally ends when the baby is born.

Timeline from conception to implantation

fertilization egg sperm
Through sexual intercourse, sperms are ejaculated into the vagina and they swim up the fallopian tubes and meet the egg there, creating a fertilized egg that will travel down the tubes to the uterus.

The fertilized egg implants itself into the endometrium of the uterus and lo-and-behold! Pregnancy is established. Let’s break this process down a little further.

1. Ovulation and ejaculation

To begin, one of the two ovaries in the female gears up for the pregnancy. In one ovary, the follicles from which one mature egg will emerge start to develop. Although many follicles mature, only one follicle will release a mature egg each month. The fimbriae catch the mature egg and sweep it into the fallopian tube. This process is called ovulation.

In the bodies of males, about 100 million to 200 million sperms are made each day. These sperms, after being ejaculated into the vagina of a female, swim up the uterus and into the fallopian tubes.

Each ejaculation releases semen containing about 100 million to 400 million sperms which are able to survive in a woman’s body for about 3 to 5 days. Although 100 million to 400 million sperms might seem like a staggering number, 99% die en route and only 1% reaches the fallopian tube. The number of sperms which reach an egg at last is around 200 or less.

2. Fertilization

Fertilization refers to the meeting and the fusion of an egg and a sperm. Usually, only one sperm will fertilize one egg. Once the sperm fuses with the egg, a barrier called fertilization membrane is made around the fertilized egg, which bars the other sperms from entering the egg. In the next 28 hours, the egg goes through cell divisions as it travels from the fallopian tube to the uterus.

3. Implantation

The fertilized egg goes through cell divisions for a week to about 10 days after fertilization and finally reaches the uterus. The fertilized egg, now termed a blastocyst, reaches the uterine lining called the endometrium. When the egg burrows into the endometrium, it connects itself to the mother’s body and is finally implanted. Once implantation takes place, pregnancy is established.

Success rates of conception and implantation

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Sperms can live for 3 to 5 days, but the egg can live for only 1 day. So, if you’re hoping to get pregnant, it’s all about the timing. The probability of fertilization in case that you have intercourse on your ovulation day is said to be 10 to 20%.

The success rate of implantation is said to be 20 to 30%. Should an egg implant itself in areas outside the uterus like a fallopian tube and an ovary, this is an ectopic pregnancy which cannot be allowed to continue.

As timing is of utmost importance, knowing when your ovulation occurs is helpful in getting pregnant. What you can do is to chart your basal body temperature (BBT) diligently each day and predict when your ovulation day is.

Bleeding from implantation

When a fertilized egg implants itself into the endometrium, the villi of the egg might hurt the uterine wall. At that time, you might feel mild pains and have some bleeding. This is called implantation bleeding and doesn’t necessarily happen to everyone.

Pregnancy signs after implantation

A fertilized egg, after undergoing cell division, implants itself and continues to grow in the uterus. You might see or feel some of the following changes in your body once pregnancy is established:

  • Implantation bleeding
  • Tightness in your chest
  • Lower abdominal pains
  • Changes in emotions
  • More visits to the restroom
  • Headache
  • Changes in food preferences
  • Feeling thirsty
  • Feeling tired

Some of these signs might be your common premenstrual syndrome (PMS). To distinguish PMS and pregnancy sign, it’s best that you monitor changes of your body on a daily basis.

When should I use the pregnancy test kit?

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You can easily get your hands on a pregnancy test kit, but you’ll get the most accurate result a week after your period is supposed to start. If you use the test kit correctly, the results are 99% accurate. Make sure you follow the instructions on the manual well to be able to get accurate results.

Knowing the process from conception to implantation makes difference

couple bed talk
If you think about how low the success rates of fertilization and implantation are, the process from conception to implantation seems miraculous, doesn’t it?

Knowing what happens in pregnancy might help give you a deeper understanding and appreciation of life – don’t keep it to yourself! Share these stories with your partner, and join your hearts as one as you continue to wait for the miraculous birth of your baby.