Conception through the ages: Can you get pregnant at 30, 35, 40 and 45?

Jul 9, 2014 at 5:27 p.m. ET

Let's take a closer look at your overall conception odds through the ages.

As a medical fertility specialist, I talk to women and their partners regularly about getting pregnant. And while they've got lots of questions, ranging from nutrition to lifestyle to what kind of underwear the guy should wear, this... no surprise... is the most common concern:

"Am I too old to have a baby?"

Believe it or not, women 45 and up can still conceive, but most will need medical help. The older she gets, the more challenges she'll face. So, once and for all: How old is too old? Should you freeze your eggs? And if so, when?

Let's take a closer look at your overall conception odds through the ages. Here's a medical breakdown of getting pregnant at age 30, 35, 40, and 45.

Age 30

At this age, you've got a 20 percent chance of getting pregnant each time you have sex during your "fertile window" (five days leading up to, and the actual day of, ovulation).

This is a great time to be thinking about getting pregnant, because women at this age typically don't have significant medical issues, and their fertility is (generally) in good shape.

The focus here, though, is on lifestyle. Are you at a healthy weight? Check out your BMI, and make sure you're in a good range. How about folic acid? We generally recommend women start thinking about getting enough before getting pregnant, and the easiest way to get it is through a prenatal vitamin. Finally, are you on birth control pills? If so, you'll probably want to stop those a few months before you officially start trying, so that your body's hormone levels can readjust.

Age 35

Most women at 35 are still going to have good fertility, but it's now that we're starting to see some bodily changes.

Age 35 isn't a cliff where fertility suddenly drops off, but every month you are losing hundreds of eggs, and these eggs aren't replenished. So while a year of trying to get pregnant is considered normal for a woman age 30, I give my 35-year-old patients six months. After that time, we'll do a full medical evaluation, because we don't want too much time to pass and reduce her chances further.

Also, if you're 35 and not ready to get pregnant quite yet, this is a time I would recommend freezing your eggs. Chromosomal abnormalities go up with each age, and that's because just like everything else in our bodies, eggs don't work quite as well as we get older. So do consider freezing your eggs if you know you want to have babies eventually, just not right now.

Age 40

At this age, you've got a 5 percent chance of getting pregnant during your fertile window.

If you're thinking of getting pregnant at this age, get evaluated by a doctor right away. Together, you two can determine your fertility and treatment options (such as IVF) available to you, because even the passage of one year can have significant impact now.

The upside of getting pregnant at 40? Things may be a little easier for you and your family financially, and chances are you're a bit more career-stable. So while there are medical concerns with having a baby at this age (the Down's rate, for example, is about 1% at age 40), there may be advantages to the living situation you welcome your new baby into.

For any woman trying to conceive, there are a couple of things I recommend: either getting on a prenatal vitamin, or taking a natural supplement like FertilityBlend. Both ensure adequate intake of folic acid; FertilityBlend has the added advantage of other supplements that may help prime your body for conception. Research has shown it to be effective in some patients, including those in a Stanford University study I participated in, so if you're looking for a natural option to aid the conception process, that's one I recommend to patients.

Age 45

The chances of you getting pregnant at age 45 are less than 1 percent each month, and most women who try to get pregnant now will not be successful.

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However, it's not all doom and gloom; I know many success stories for women age 45 when it comes to having a baby. The key? Using your own, frozen eggs, or getting an egg donor. The decline of fertility is related to your eggs, not your uterus, so if healthy eggs are available, pregnancy is certainly not out of the picture for you.

Questions? Feel free to ask me in the comment section below, and I'll weigh in. Good luck to all of you on your fertility journey.

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