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Age Factors


Fertility In Your Mid-30’s And 40’s

So many women choose to get pregnant later in life, waiting until their mid-30’s or later to begin trying. Unfortunately, the term “biological clock” is an apt one because as a woman’s body ages her eggs age as well. It is well known and scientifically proven that a woman’s fertility decreases with age beginning at 30 years old.

At birth, a female has about one million follicles present in her ovaries. By the time she reaches puberty the number will have dropped to around 300,000. It is known, but not completely understood, that only a few hundred eggs will ovulate during a woman’s reproductive lifetime and the rest die off continuously by a process called atresia. For many women, their best reproductive years are in their 20’s with fertility beginning to decline in the early 30’s. A healthy, fertile 30 year old woman has about a 20% chance of getting pregnant each month. By the time she reaches the age of 40, her chances are less than 5% per month….a big decline. This is attributed to a decrease in the number of eggs and a decrease in egg quality, what Dr. Ramirez likes to call “age related egg factor”. So, not only does a woman have fewer eggs but they are of very low fertility potential as well. This factor is a significant cause of infertility and miscarriage in older women.

**Up until now, no one really knew how many “good” eggs exist in the 35+ woman…and although it is still not 100% certain, a recent 2013 study has come out with some answers. The study found that 2 out of 20 eggs retrieved from 40 yr old women were chromosomally sound and had the potential of fertilizing and implanting successfully.

We know that as the eggs age, the internal structures of the egg become more debilitated and so are less likely to thrive. One of these deficits is the chromosomal structures which become more brittle and can lead to chromosomal abnormalities as the cell (embryo) is dividing. Without doing genetic testing, these cannot be detected. Even chromosomally abnormal embryos can turn into good looking embryos but not necessarily into pregnancies. On the other hand, it is clear that while the eggs decline in quality, a woman’s uterus is not affected by the aging process. It is for this reason that you see headlines of “grandmothers” acting as surrogates for daughters who cannot bear the child themselves.

Treatment Paths For Women Over 35

Patients who have age-related infertility are given several choices when Dr. Ramirez counsels them. He will discuss the pros and cons of an intra-uterine insemination (IUI) or in vitro fertilization (IVF) cycle. The patient is always welcome to try intra uterine insemination, even if they are over 40 years old. At this age the pregnancy rates for IUI are at best .05%. If the IUI fails then an aggressive treatment plan is formulated with in vitro fertilization, IVF, strongly advised.

For those under 40, Dr. Ramirez does not recommend more than four IUI cycles. Between 35 – 39 years, the pregnancy rates for IUI will range from 15% -5%. If those fail, then IVF will be strongly recommended as well. IVF (in vitro fertilization) helps to overcome the age factor problem by increasing the number of eggs retrieved and therefore, statistically, increases the chances of finding the perfect egg. By the age of 40, with IVF and using her own eggs, a woman increases her chances of pregnancy from 5% if she were trying naturally to 33% per cycle at our center. Unfortunately, because of pregnancy and miscarriage losses the delivery rate is 13%. The odds of a successful pregnancy with older eggs can be somewhat improved through IVF with Assisted Hatching and PGD.

What that means for older women (35 years and older) is that it may take a lot more attempts to achieve a pregnancy, but as long as the ovaries still respond and put out eggs and embryos, then you have a good chance. Also keep in mind that pregnancy rates are highly variable among clinics so the clinic one chooses to go to is very important.

There is another option for those who fail multiple times and are of an advanced maternal age. The decision to pursue donor oocytes for women who have failed multiple IVF cycles or are over the age of 45 is a personal one but one that had proven very successful for those who have chosen donor IVF cycles. With donor eggs and IVF, the chances of pregnancy increase dramatically due to younger and healthier eggs, to 75% with a 59% delivery rate. It has been statistically shown there is no decrease in success rates when the woman elects to use eggs from a young donor, in fact it reverses the age-related decline in female fertility significantly.

Diagnostic Tests For Age Related Infertility

There are several ways to test for age factor infertility. At the Fertility & Gynecology Center, we can test our patients in-house in our fully accredited hormone laboratory. Dr. Ramirez and his lab assistants will take three simple blood tests to check hormone levels and ovarian function. These tests may also help to diagnose infertility in a younger woman who may be experiencing “Premature Ovarian Failure”.

Hormone Testing To Assess Ovarian Function

  • Basal FSH: FSH (follicle stimulating hormone) is the main hormone involved in producing mature eggs in the ovaries. If this test shows that the patient has high levels of FSH, it is a signal that the brain is trying to increase the performance of poorly functioning ovaries.
  • Estradiol: Estradiol is the most important type of estrogen found in a woman’s body. It is responsible for keeping the eggs healthy as well as facilitating pregnancy. If the test shows a high Estradial count then there is a problem with egg numbers and/or quality.
  • AMH: AMH (anti mullerian hormone) is an “indirect” test for ovarian reserve and does not necessarily predict how a patient will respond. It can be useful in predicting ovarian reserve but not an absolute indicator. We do not have the technology to know how many eggs are present without doing a careful dissection of the ovaries. The AMH test is to help predict, as much as possible, whether the ovaries will yield many follicles upon the hyperstimulation that occurs with giving increased amounts of FSH.

Ultrasound Evaluation To Assess Egg Quality

  • AFC or “Antral Follicle Count”: Dr. Ramirez will perform a trans-vaginal ultrasound in order to evaluate the patient’s uterus, uterine cavity and ovaries. If this is done prior to ovulation, the ultrasound can also show whether there are fibroids or endometrial polyps present. The examination is to establish the number of small follicles in the ovaries. If the follicle count is lower than 10 it may be an indication of a declining ovarian reserve.


Keep in mind: It is a total misunderstanding or misinterpretation to say that a low AFC or low AMH indicates that you are infertile, that your ovaries won’t stimulate or that you won’t have good eggs! Taken together with an elevated FSH, these measurements serve as red flags from a time point of view. It means that you may not have as much time to get pregnant using your own eggs as you might have thought. Since we cannot predict when you will run out of time, time becomes a critical consideration.


The Fertility & Gynecology Center - Monterey Bay IVF
9833 Blue Larkspur Lane
Monterey, CA 93940
Phone: 831-649-4483
Fax: 831-649-9010

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