(WOMENSENEWS) — Dr. David Keefe is Professor Stanley H. Kaplan of New York University School of Medicine, Chair of Obstetrics and Gynecology, and specializes in endocrinology of reproduction and infertility. He recently talked on the phone about what is known and what remains a mystery about infertility.
This year Women’s Health Conference You have provided the latest information on infertility. What kind of updates are there?
Many infertility is not explained. So I focused my updates on the forefront of fertility research. What are we learning and where are we heading to understand unexplained infertility?
It turns out that the majority of unexplained infertility is actually related to chromosomal problems that appear in the embryo itself, rather than being transmitted through the egg or sperm.
They occur as the egg matures, or during or after fertilization, and there are new technologies widely used in this today. This is usually used after a couple has tried the first low-tech approach. If it fails and they go to in vitro fertilization, [in vitro fertilization]Approximately 70-80% of women undergoing in vitro fertilization use next-generation sequencing to test embryos for chromosomal problems before they are returned. This is this genomic technology that will revolutionize medicine.
Before transferring the egg, make a small scratch on the shell around the embryo, put a part of the embryo destined to buckle like a somatic cell, then remove some of those cells and all Check the chromosomes and make sure there are two copies of each of the 23 pairs of chromosomes. [And if a chromosome is missing that egg won’t be implanted.].. By doing so, the success rate is about 65%, even if the woman has only one normal embryo. And it is not affected by her age.
Therefore, many of the effects of aging appear to be mediated by the presence or absence of chromosomal abnormalities in each embryo. Currently, the probability that a chromosome will have a normal embryo decreases with age. However, it often allows women to avoid miscarriage. This is because miscarriage, which increases with age, is due to chromosomal abnormalities. Therefore, simply transplanting a chromosomally normal embryo can significantly reduce the risk of miscarriage.
Another thing we are doing is selective egg freezing. By removing and freezing eggs when a woman is still giving birth, the birth rate at that age can be reduced.
What are you studying?
My study is investigating why there are so many chromosomal abnormalities in the embryos of older women. No one knows the reason. But for some time we have been working on the theory that it involves telomeres, a very specific part of the chromosome.
Telomeres have been found to be very important in regulating the aging of many cells, from plants to humans. They are involved in chromosomal alignment very early in development. The genetic or pharmacological destruction of telomeres in mice using animal models can make them indistinguishable from older females in that they have fewer eggs and are not easy to transplant. I was able to show.
Many women have also been found to have a genetic condition that destroys telomeres and accelerates aging of the reproductive system. We continue to study the ability of eggs to measure telomere length to predict the presence or absence of these chromosomal abnormalities in embryos. Applying this study directly will help women decide to freeze their eggs. Do they need to? Or is it one of the selected people who don’t have to worry about this because they are more likely to give birth later? We want to help women make more personal decisions.
To back up a little, what do we mean when we say infertility?
It has a specific definition. For women over the age of 35, it means that they have failed to get pregnant for at least 6 months. Under the age of 35, she failed for a year. The criteria differ by age because the fertility rate declines with age after the age of 35. So it’s a kind of moving goal and we don’t have to wait too long and force women to meet stricter standards. And behind these numbers is the reality that an essentially normal couple has only a 20 to 25 percent chance of becoming pregnant. I think many people are shocked by the relative inefficiencies of human childbirth. Therefore, the definition is highly dependent on the age of the woman, as women over the age of 35 do not want to wait too long.
What are some of the causes of infertility?
Fertility can be broadly divided into female-only factors, male-only factors, and combinations of factors. Therefore, women may have irregular cycles, such as not ovulating monthly due to polycystic ovary, strenuous exercise or dieting, or hormonal imbalance. there is. Both of these can interfere with ovulation. Endometriosis or previous infections can obstruct the fallopian tubes. There are uterine factors such as uterine fibroids. Many women have them, but the presence of uterine fibroids themselves does not reduce childbirth. However, if a uterine fibroid develops inside the uterus that requires the embryo to attach, it can have a devastating effect on implantation and cause miscarriage. Scar tissue can be a problem if she has been previously treated to destroy the normal and protective layers of the uterus.
From the male side, it is basically summarized in sperm problems. Low count, low motility, or both. Ejaculation problems, some men can’t or ejaculate in the bladder. Some men have problems with erections, and some have very low sperm production due to neurological problems or testicular failure due to previous trauma or some genetic condition. And if you’re probably more infertile than any illness, you can have this a little. It is not uncommon for a single problem to occur.
And behind all these causes of infertility, whatever the problem, after all, there is a recurring theme that women’s age is the only and greatest predictor of successful treatment. Therefore, even if a couple comes in and the man does not have sperm in the semen analysis, the best predictor of whether they will become pregnant is how old she is.
Because even in that seemingly dire situation, a biopsy can take a few sperms from the testicles, which depends on the viability of the female egg. And it drops slowly at first after 35, accelerates after 38, and mainly fails after 43.
How many women are affected by infertility?
It is generally believed that about 12 percent of couples are affected by infertility. It’s pretty fulfilling and goes up with age. Therefore, the number is low for young women, and can be much higher for older women, especially those in their late 30s and early 40s.
What are the current treatments?
Typically, you run a limited number of validated tests to ensure that all components are present. I would like to make sure that the woman is ovulating. The presence of a regular menstrual cycle of 25-34 days generally indicates an ovulation cycle. I would like to make sure that there is no hormonal imbalance. There is no hypothyroidism, no increase in prolactin, and no excess of androgens in men. I would like to make sure her fallopian tubes are open and that my uterus is normal. Then check the male sperm. Look at your motility, concentration, and shape, as some are unusual. And after doing that, the first treatment is targeted at a specific condition.
If her fallopian tubes are blocked, proceed directly to in vitro fertilization.
More commonly, you may see irregular cycles. In that case, regulate ovulation. For hypothyroidism, treat hypothyroidism.For high prolactin [a hormone produced by the pituitary gland], Treat high prolactin. If the hormone called polycystic ovary is out of balance, a very mild stimulant will induce ovulation. This is a pill that women take for 5 days.
And, in many cases, especially in professional practice, we often see women with all tests normal. We call it unexplained infertility and it is very common. In my practice, probably 60 percent of women have it. In that setting we can still help them.
There are very effective treatments for unexplained infertility. In general, use a very low-tech procedure to optimize the timing of ovulation, focus the sperm on a small drop, and then place the sperm drop on top of the uterus where the egg falls. In doing so, some of the relative inefficiencies of human reproduction can be overcome. We do it a limited number of times and if that doesn’t work, go to IVF.