Assistant Division Director
Walter Reed Medical Center
Associate Director, REI
Johns Hopkins School of Medicine
One factor in whether a couple can conceive, and carry, is the lifestyle they lead and the impact it has on their bodies.
For the most part, Black women who go to a fertility clinic weigh more than other patients, and have a higher Body Mass Index, or BMI. Below is data from one study on these weight disparities, and most other studies reflect a similar pattern.
BMI is a formula to identify how much weight someone has on their body once we correct for their height. The method to calculate BMI is below. BMI doesn’t take into account bone density or ethnicity, but having a BMI on the high end of the range, say approaching 30 or 40, is clearly an issue.
For women trying to conceive naturally, a higher BMI correlates with a lower likelihood of success.
And this is true for men (unless they are severely underweight) as well as for women, as you can see below.
And if a woman, or couple, decide to do IVF, being too light or too heavy correlates with lower live birth rates for nearly all patients, as you can see here.
If you’re trying to get pregnant and your BMI is at the extremes, it’s important to talk to your doctor about realistic goals you can set to get pregnant quickly and safely.
For some women, delaying treatment to lose weight can be of real help (one example is women with Polycystic Ovarian Syndrome) but for others, especially for women approaching their 40’s, delaying treatment to lose weight can actually reduce their odds of success.
Furthermore, a woman’s weight will impact the safety of her pregnancy and the health of her children. One example of this would be pre-eclampsia, which can be dangerous or even fatal for the mother and fetus.
Here you can see the clear correlation between a woman’s rising BMI and her increased risk of developing pre-eclampsia.
On FertilityIQ, you’ll find a detailed course covering most major lifestyle factors and how they’re related to conceiving. For the moment we’ll just briefly touch on diet.
First, diets that incorporate more whole grains, vegetables & fish, like the Mediterranean diet, correlate with higher pregnancy rates for women trying to conceive naturally, as you can see below.
That’s also true for women who undergo IVF, with relative success rates nearly 40% higher for those who adhere to a Mediterranean-like diet.
On the other hand, consuming higher amounts of fast food and fried food often correlate with lower rates of success. That’s true for women trying to conceive naturally or in treatment.
Another issue that tends to disproportionately impact Black fertility patients is what’s known as a “tubal factor.” Below are three studies that compare the prevalence of tubal factor issues amongst fertility patients by race. While the definitions of “tubal factor” varied between the studies, in each one, Black women had meaningfully higher rates.
As you may remember from the first lesson on human reproduction (and can see in the diagram below), most women have two ovaries and each ovary has a fallopian tube connecting it to the uterus. If those fallopian tubes are scarred or blocked, it will make it difficult or impossible for the sperm and egg to meet, or for an embryo to reach the uterus.
Tubal factor issues can be caused by any number of issues, including sexually transmitted diseases like chlamydia or gonorrhea. When left untreated, each can cause damage within the uterus and fallopian tubes.
If both fallopian tubes are blocked, IUI is not a viable treatment option — conception still won’t be possible with anything other than IVF.
If only one fallopian tube is blocked, artificial insemination, or IUI, can work. That said, the odds of success really depend upon where the blockage occurs.
If the blockage is found closer to the uterus, what’s known as proximally, after three IUIs, 36% of women will get pregnant. If the blockage is seen closer to the ovary, or distally, after three IUIs, success rates are closer to 12%.
IVF has the benefit of bypassing the fallopian tubes because eggs are surgically removed directly from the ovary, fertilized outside of the body & then placed back into the uterus. In effect, IVF takes blocked fallopian tubes out of the equation.
Success rates for women with tubal factor issues are similar to most other IVF patients. As you can see below, for women under age 35, about 40 - 45% of IVF cycles lead to a birth. However, with every passing 2 year interval, the odds of success drop by about 10 percentage points so that by the time a tubal factor patient reaches her early 40’s per cycle success rates approach single digits.
If the fallopian tubes aren’t just blocked, but they’re also filled with liquid, your doctor may refer to this as a hydrosalpinx. As you can see here, when doctors remove the damaged tube, or tubes, IVF success rates can sky-rocket.
A uterine fibroid is a tissue growth in the uterus, and it can also be referred to as a “leiomyoma” or “myoma.” While the term “growth” can be off-putting, fibroids almost never become cancerous.
As you can see below, not only are Black women more likely to develop fibroids than Caucasian women, the majority of Black women have at least one fibroid by the time they reach their reproductive years.
As you can see in both studies below, Black fertility patients are more likely (than Caucasian women) to have their fertility challenges attributed to a fibroid.
For some women, fibroids can be painful or cause heavy bleeding. In this case, surgical treatment can dramatically reduce symptom severity, as you can see from the study below (conducted on over 300 women, half of whom were African American).
From a fertility standpoint, the data is hard to interpret on how treating a uterine fibroid improves a woman’s ability to conceive. The issue likely comes down to where the fibroid resides.
There is “fair” evidence that if a fibroid distorts the uterine cavity (often referred to as being “submucosal or intramural with a submucosal component”), removing it through hysteroscopic myomectomy improves pregnancy rates. Fibroids that distort the shape of the uterine cavity are an issue because they interfere with an embryo’s ability to attach to the uterine wall which, as you’ll recall from the lesson on human reproduction, is the fifth requirement for a woman to conceive.
However, if a fibroid doesn’t appear to distort the uterine cavity, the evidence is less convincing that it impairs fertility or that removing it improves the odds of success.
Removing a fibroid is a surgical procedure (though some approaches are more invasive than others), and any surgical procedure on the uterus has to be taken seriously. Removing a fibroid can cause scarring to the uterus and create further fertility challenges. It can also weaken the walls of the uterus, committing the woman to a C-section or early delivery, which in-and-of-itself has issues for the offspring.
Unfortunately, Black women are more likely than Caucasian women to suffer a miscarriage following their fertility treatment, as you can see below.
It’s rare for a woman to suffer multiple miscarriages, and often the next pregnancy will result in a live birth. Typically, around 20 - 25% of women experience one miscarriage, about 5% of women experience two and 1% experience three or more.
If a woman has a miscarriage, or is likely to miscarry, she has a few options.
Following a miscarriage, one option is to have a D&C, or “dilation and curettage” procedure, which is a surgical procedure to remove any remaining tissue from the uterus.
A benefit to having a D&C is it allows the doctor to collect the “products of conception” for genetic testing. This can provide valuable information why a woman miscarried. If a woman wants this testing done, she needs to explicit with the doctor before the D&C. It may be performed after the fact, but with more work and complexity.
If the products of conception are genetically “abnormal,” the miscarriage likely failed because the embryo had the wrong number of chromosomes. This is the case in about 60% of miscarriages.
In the future, if the woman undergoes IVF, chromosomal testing of the embryos before her transfer can lower the odds of a future miscarriage, and this is especially true in older patients. As you can see from the data below, using genetic testing (known as “PGS,” “CCS,” or “PGT-A”) can dramatically lower miscarriage rates for women 35 years and older.
If the products of conception are chromosomally “normal,” things may be more complicated. The miscarriage is likely due to another factor, for example something related to a woman’s uterus. This is the case in about 40% of miscarriages.
In this case, doing another IVF probably won’t address the underlying issue, and so proceeding right to IVF, without some sort of other inquiry and intervention, will likely result in the same outcome.
If you have a D&C performed but don’t manage to have the “products of conception” tested, you may still be able to get answers, thanks to “Rescue Karyotyping.” After most D&C procedures, a sample of the extracted tissue is sent to a pathology laboratory, and preserved in a wax block. Rescue Karyotyping allows a small slice to be shaved off of that wax block and tested, even months or years after a D&C.
Doing a D&C can carry some risk. It risks scarring of the uterus or leading to adhesions that can make it harder for a woman to conceive or stay pregnant. It’s hard to say how often adhesions are left, but likely lower than 5 - 10% of cases.
There is evidence that if your doctor uses a manual pump approach, rather than a mechanical pump approach, during the D&C, it can lower the risk of scarring and adhesions. Below is data from a study of 144 miscarriage patients and, as you can see, adhesion rates tended to be lower using a manual pump approach.
There are alternatives to undergoing a D&C. For one, a woman can wait to miscarry naturally, which helps avoid an intervention, but this can be a drawn-out, multi-week process. To address that, she can also take a medication to speed the process along.
However, miscarrying naturally or with medication can make it harder to have the “products of conception” tested, and if that’s what she wants, it requires her to collect the tissue herself and bring it to her provider.
While Black men aren’t necessarily more prone to having fertility issues, they may be more reluctant to have their fertility tested or acknowledge there could be an issue. Generally speaking, a male factor issue is identified to be a major contributor in roughly 50% of couples that struggle to conceive.
The first step in identifying if there is a male factor fertility issue is for the man to have a semen analysis performed (some doctors advocate for two to be taken). The test involves the man abstaining from masturation or intercourse for a few days before providing a semen sample. Often, that’s the extent of it.
Skipping the step of doing a “semen analysis,” is a big mistake. It can blind the doctor and couple to the true, underlying issue and cause the woman and couple to undergo painful, costly, and needless treatment.
The semen analysis is not perfect, but it can be a good indication if a man’s sperm “concentration,” “motility” or “morphology” are below normal ranges.
Men can still conceive with below-normal ranges, but as you can see in the table below, it may take longer to achieve a pregnancy, especially if there are multiple parameters that are low (or if one crucial parameter is extremely low).
TMC, or Total Motile Count, is a great shorthand for the results of a semen analysis: it’s the number of sperm that swim forward in a man’s ejaculate.
As TMC goes down, so too do the odds of success with treatments like IUI. But as you can see in the graph below, the rate of decrease is pretty subtle between each interval. Many wonder whether should there be a hard cutoff for “TMC and IUI,” but based on this data, it can be hard to say precisely where that would be.
If a couple needs to resort to IVF because of a male factor issue, success rates are typically in line with other patient types, and are often still most correlated with a woman’s age.
Male factor infertility can be caused by a number of factors.
For instance, a third of men with a male factor issue have a varicocele, when the veins in the scrotum have become enlarged. If the varicocele is big enough, surgery on it can improve semen parameters. As you can see from the data below, when surgery is done before IUI, it can improve the success rates compared with doing IUI alone.
That same phenomenon is also true with regard to IVF, as you can see in the Esteves study below.
Azoospermia is a phenomenon whereby the man produces no sperm. Azoospermia impacts 10 - 20% of couples with a male factor issue. Depending upon the cause, azoospermia can be relatively easy to treat or incredibly hard.
The most common (and challenging form) of azoospermia is called Non-Obstructive Azoospermia (or Testicular Azoospermia). In this case, the testicles are prompted to produce sperm, but simply can’t follow-through. Here, sperm needs to be surgically retrieved from the testicle, using a procedure called TESE or MicroTESE. As you can see below, in about 45 - 63% of cases sperm can be found and retrieved.
If sperm is retrieved, it can be used to fertilize the eggs during IVF. But, as you can see below, success rates for patients with Non-Obstructive Azoospermia tend to be lower compared with other forms of male factor infertility.
Finally, hormonal imbalances can influence sperm quality and oftentimes these issues are easier to fix and allow the couple to conceive naturally, with no treatment.
There are lifestyle changes men can make to improve their semen parameters, so hopefully IUI or IVF can be avoided, or will be more likely to work if needed.
For starters, men should eliminate smoking altogether, which, as you can see, correlates with significantly worse concentration and morphology.
Next, moderating coffee consumption down to 2-or-fewer cups per day can be helpful, as you can see below in the correlation between male caffeine intake and IVF success rates.
Moderating coffee intake can have real benefit not just for being able to conceive, but in helping to avoid misscarriage, which as we showed in our lesson on success rates, disproportionately impacts African American patients.
As for alcohol intake, the data shows there’s likely a threshold effect for drinking. Beyond a certain limit, it clearly has a negative impact on semen parameters.
Exercise is a double edged sword. Generally speaking, more exercise is a good thing, especially if the man is overweight. As you can see here, more exercise generally correlates with improved semen parameters.
However, when investigators looked at extreme levels of exercise, there was clearly a drop in semen parameters. High levels of biking can be especially problematic.
Finally, testosterone replacement therapy (or TRT) has such a negative impact on male fertility it’s been looked at as a form of male birth control. Yet, 20 - 25% of urologists get this wrong and actually believe exogenously-taken testosterone improves male fertility. If men are taking testosterone, it’s best that they begin to stop. We say begin, because while testosterone is catastrophic for male fertility, stopping cold turkey can leave men depressed.
It’s worth noting that when men take clomiphene citrate (or clomid, the same drug we alluded to in the first lesson) and aromatase inhibitors this often raises the level of serum testosterone without affecting sperm parameters. However, this is an off label use of these medications.