Women's Healthcare Topics

Ovulation to Conception

Reviewed by James Brann, M.D.

In order to understand where you're headed, “conception”, you need to understand “ovulation”.

Oh sure, you know “what is ovulation” and “what is conception”, thanks to your health teachers, the school nurse, knowledgeable older sisters, uncomfortable squirming parents and books.

But let's fill in some blanks and get back to basics.

Women are born with 2 million eggs. At puberty, that number drops to about 400,000 which is plenty since women will only release about 500 eggs in a lifetime.

During adolescence, young women begin to menstruate and become capable of ovulation for the first time. And while you started out with all of the ingredients necessary to make a baby, your mate did not. Young men begin to produce sperm during puberty.

On average, a woman's reproductive cycle is 28 days long. Day one is the first day of a woman's monthly blood flow, or period. Each month, the uterus, located in the lower abdomen (about the size of an egg), prepares itself to host a baby. The uterus develops a cushy lining intended to nourish a baby. Reproductive hormones from the pituitary gland in the brain send a message to the woman's ovaries to release an egg every 28 days.

How to Know When You’re Ovulating
Video: How to Know When You’re Ovulating

What is Ovulation?

This release of an egg is called ovulation. Ovulation usually occurs fourteen days into the woman's monthly cycle. A small number of women can feel symptoms of ovulation - a sharp pain on one side or the other that lasts about 24 hours. If you can tell when you ovulate, getting pregnant (conception) is often easier because you can feel your fertility!

The egg is available for fertilization (conception) for 12 to 24 hours after it's released by the ovary. If the egg isn't fertilized, the uterine lining is shed during menstruation, your monthly period. No conception, no need for the lining.

What happens during the menstrual cycle?

There is no "normal" menstrual cycle. Most women are on a 28-day cycle, but that number can be as low as 21 days to over 35 days. What's normal is what's normal for you.

  • Day 1: The first day of your menstrual period is day 1 of your monthly cycle.

  • Day 5: Estrogen, a hormone, signals the uterine wall to thicken in preparation to host an egg.

  • Day 14: The egg is released from one of two ovaries (they usually alternate month to month). The egg moves down a narrow passage called a fallopian tube.

  • Day 20-24: If the egg is fertilized it attaches itself to the uterine wall.

  • Day 28: If the egg remains unfertilized, hormone levels decrease and the thickened lining of the uterus is shed during menstruation. The process then begins all over again.

What is Conception?

When a man and woman have sexual intercourse, the man releases his genetic material, known as sperm, during ejaculation. 20 million to 250 million sperm cells are released during a single ejaculation.

The sperm are then faced with a long and perilous journey. Their goal? To fertilize an egg. The majority of sperm die in route to their intended destination. The strongest and most fortunate, 1,000 at most, will actually make it far enough to achieve their mission. Only one can actually complete it. And, more often than not, none does.

After intercourse, the sperm travel through the woman's vagina, past her cervix (the entryway to the uterus) into the uterus itself. If the sperm cells don't fertilize the egg in the fallopian tube, the unfertilized egg, travels down the fallopian tube and into uterus.

When sperm do successfully meet up with an egg, fertilization known as conception occurs. Again, the egg is fertilized in the fallopian tube where it remains for about 80 hours before making its way into the uterus. The now-fertilized egg can float around the uterus for several days before it attaches itself to the uterine wall.

The sperm provides half the genetic information, or DNA, to create life. The egg provides the other half and immediately upon fertilization, cells begin to divide and life begins.

FYI: A pregnancy test will yield a positive result 9 - 11 days after conception - when egg and sperm first meet.

Pregnancy Health Section

What's going on Hormonal during the Menstrual Cycle?

About a million things, actually. During the menstrual cycle, the body increases and decreases the amount of hormones produced. The key players are:

Estrogen and progesterone
Produced by the ovaries, estrogen and progesterone signal the uterine wall to thicken. Levels of these hormones decline if fertilization doesn't take place, and you have your period. However, if the egg is fertilized, estrogen and progesterone increase to support your pregnancy and prevent further ovulation - the release of additional eggs from the ovaries.

Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH)
Produced by the pituitary gland at the base of the brain, FSH causes an egg to ripen in the ovary before ovulation. An increase in LH signals the ovary to release the mature egg.

Gonadotropin-releasing Hormone (GnRH)
Produced in the brain, GnRH signals the pituitary gland to start producing FSH and LH.

Human Chorionic Gonadotropin (hCG)
Within a few hours after implantation, the egg begins to produce Human Chorionic Gonadotropin (hCG). The release of hCG signals the ovaries to produce more estrogen and progesterone to prevent further ovulation. It's this increase in hCG levels that pregnancy tests measure, i.e. that's why they read positive.

So, Are You Pregnant?

Most women want to know whether they're pregnant or not as soon as possible. That's a good practice. The sooner you know, the sooner you can stop any unhealthy behaviors and activities.

Early Tip-Offs That You're Pregnant

Indicators of Potential Health Issues

These are unusual conditions and should be taken seriously and discussed with your doctor. Early indicators of pregnancy may point to potentially serious problems so if you experience any of these symptoms see your doctor.

It's important to remember that you can become pregnant even though you employ a method of birth control. It's never a good idea to assume that you aren't pregnant simply because you and your partner use birth control.

What about Those Pregnancy Test Kits?

Pregnancy Test Kits
Video: What about Those Pregnancy Test Kits?

They're reliable to a point. Many cases of false positive and negative results have been reported, but most of these can be ascribed to testing too early or improper test samples. The most common mistake in reading a pregnancy test stick is that they need to be 'read" in the first few minutes. If you wait too long, you're more likely to get a false positive result.

Over-the-counter pregnancy tests measure elevated levels of hCG, human Chorionic Gonadotropin, in a woman's urine. And with advances in testing technology, results can be accurate as early as the day of a missed period, though as more time passes, test results will be more reliable.

If you initially test negative (not pregnant), but your period hasn't started when it should, wait a day or two and test again. If you have any doubts or concerns, make an appointment to see your doctor for definitive testing. It'll also ease your mind and cause less worry at a time when you shouldn't be worried.


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