Sometimes, it’s even difficult to know what is the right thickness. This is also something that makes it very difficult to compare different studies because everyone can have a certain thickness as the minimum or as the best one, so f.e. in our case, we work with the 6 millimeters as the minimum thickness in an egg donation or a cryo transfer, but this is a scan that is done on day 9-10, and once we reach that 6 millimeters thickness, we are sure that once we do the embryo transfer that is usually done 1 week or 10 days later, the thickness is going to be good. Other clinics may work with 7 millimeters, other ones prefer to work with 8.5, some clinics prefer to work with a pattern triple-line or not. What we do when we don’t get that minimum of 6 millimeters that we are looking for?
We prepare someone for an embryo transfer, sometimes we just need to increase the dose of estrogens, we prefer to work with a fixed pattern of high doses from the very beginning. I know that there are clinics and their protocols start with 4 milligrams, then go up to 6 milligrams, and some of them go up to 8 milligrams of estradiol. We usually start from the very beginning with 8 milligrams, so it’s 2 milligrams in the morning, 2 milligrams at midday, 4 milligrams at night, and we do the first scan 8-10 days later. By doing that, I would say that probably 90-95% of the patients have the right thickness.
When this doesn’t happen, we can go up to 10 or even 12 milligrams and take 4 milligrams every eight hours. If we manage to get the right thickness, that’s fine, we advise patients to keep doing the same doses. When this doesn’t happen, and we have to cancel the cycle because we don’t get the right thickness, we may sometimes use drugs like Cialis, which is the tadalafil between 5 and 10 milligrams a day. These drugs are supposed to increase vascularization, make the vessels wider. Then it should be easier for the estrogens to reach the endometrium and to improve the thickness. In some patients, it works, in some other patients, it doesn’t work. Sometimes we may change the way they are taking the estrogens, and we can shift from oral to transdermal and in this case, we may use patches, or we may use a cream to give the estrogens and changing the way.
When you make it through the skin the estrogens go straight away into the bloodstream and go straight away into the uterine. When you take them orally, there has a first passage through the liver that may remove part of the estrogen, so sometimes is a good idea to use patches of creams and even a combination of oral and patches, and this may be enough to increase. In those cases in which the thickness keeps being really low despite using these drugs, despite combining patches, creams, or increasing the doses, these are difficult cases. Certain studies have confirmed that the endometrium can still be receptive when they are 4 or 5 millimeters thick. In this kind of endometrium, one option can be carrying out the transfer, or carrying out a test to confirm the endometrium is receptive and if it is, try to see it. I have patients with endometriums of 4.5-5 that have been successful, and they’ve gotten pregnant.
There are other cases in which we have tried a protocol where we have combined high doses of vitamin E plus pentoxifylline for 2 or 3 months, and then we have tried to prepare the endometrium, and I’ve got probably 2 or 3 patients where it worked. We don’t have so many patients with this problem, but in the 2 or 3 cases in which I’ve tried this combination of vitamin E and pentoxifylline, I’ve managed to get a better endometrium. Sometimes, I’ve got a completely normal endometrium, but if the patient had an endometrium of 3.5, I’ve managed to increase it up to 5-5.5, and I’ve got pregnancies, so this could be the only different thing apart from increasing doses, combining patches, or adding tadalafil or viagra in some cases., I’m not really fond of viagra, I prefer tadalafil, in some cases, those can help to improve the thickness of the endometrium.