What Are The Odds Of Getting Pregnant?

After having three children in four years, I admit that sometimes, I am a little afraid of my husband looking at me the wrong way. Because it seems like that’s all it takes for my body to fall pregnant yet again.

Some women struggle with the pain of infertility while others seem to become pregnant very easily, so it seems safe to say that there is no rhyme or reason to that little thing called the miracle of life.

But just how much of a miracle is getting pregnant? Isn’t it something our bodies are designed to do?

Well, the answer may surprise you. 

Aside from factors such as a woman’s age, weight, genetics, and health factors, the first obstacle is getting the timing right. You and your partner have to have sex on just the right day; a woman can typically get pregnant around days 14-18 of her cycle. Outside of that, she doesn’t have an egg to be fertilized.  And even if conditions are prime time for baby making, although 300 million sperm may be released during sex, only 3 million of the little guys make it into the uterus for a chance at fertilizing an egg. That’s less than 1 percent! The life span of sperm is also limited. Sperm can only survive for up to 48 hours and it takes 10 hours alone for the sperm to reach a woman’s fallopian tubes, which is where fertilization occurs.

Next, sperm basically face an obstacle course of mighty proportions before they can reach their prize. The fallopian tubes are nearly a foot away from the opening of the vagina; in other words, miles and miles for the tiny sperm.

A woman’s body seems designed to make it as hard as possible for the sperm to survive the long trek to the fallopian tubes. First, the natural acidity in the vagina kills off many sperm and the cervix blocks and traps many of the survivors.

During ovulation, usually only one ovary releases an egg, so once the sperm have made it to the uterus, should they choose the wrong path, they are goners as well.

The sperm that choose correctly immediately face another battle as hair-like fibers and muscle contractions of the fallopian tube beat back the swimming sperm in an attempt to block their passage. Many sperm get trapped in the walls of the tube and even more succumb to white blood cells that act like bodyguards, literally attacking and killing stray sperm.

In the end, out of 3 million sperm, a hundred obstacles, and just the right conditions, only a few sperm will make it to the egg. Despite all of the obstacles, one report states that for couples in the optimal conditions, there is a 1 in 20 chance of getting pregnancy from one act of intercourse. 

Phew!

Who knew baby making was such hard work? 

{ MORE: Should You Freeze Your Eggs? 7 Facts to Consider }

Did you have any difficulty getting pregnant?