Can lining be too thick?

molly84

So I have been wondering if your lining can be too thick and I was interested in anything that you all have heard. The reason I'm wondering is because of my recent failed IUI cycle. My nurse told me today that my lining was 11 mm the day before our first IUI. We did back to back ones. Then, they put me on progesterone suppositories to thicken my lining. I didn't think anything of it at the time, but now I'm wondering two things...why was I even put on the progesterone? And is it possible for lining to be too thick to implant? Or maybe that doesn't even make sense and I'm pulling at strings. I was just curious about anything that you all already know! I'm also planning on asking my nurse this tomorrow at my baseline ultrasound. Thanks for any input!!

molly84

I just realized that I probably should have posted this to the ttc board instead. My apologies.

Sigh202

I was told that lining cannot be too thick, just more cushioning for the embie to implant.

molly84

Thank you! That does make sense. : )

Pintobean39

Mine was 15 with my FET.

ddvj79

I was told that the lining could be too thick & the embryo could fail implanting because of that. Also, I hear that it is common in people of Asian orgin. I am Indian myself so this does apply somewhat to me too. Thats kind of the reason why my RE said no fresh transfer for only FETs & they will be monitoring my lining very closely to determine the optimal time to do the FET 

siempre595

I saw a study somewhere (I will look for it) that implantation rate increases from 8 up to 16.  Below 8 is much less likely to implant (I had this problem with Clomid, which is why I was reading about it).  But up to 16 the rates of implantation increased.  Over 16 there was some drop off.  

Also, I think progesterone changes the quality of the lining, estrogen makes it thicker.  That is my basic understanding.  I was on a ton of progesterone with all my clomid cycles, and never got a very thick lining.  My first IVF cycle, I got a 12 on day 9.  

starlightgator

This cycle mine was 15 before retrieval.

Pintobean39

That's right @siempre595‌ it's the estrogen that thicken it. Progesterone keeps it from shedding.

I actually searched on the bump I think when I was doing my FET and my lining was 11 and my dr still wanted it thicker. Someone posted this study you are talking about. It was interesting. I'm mobile so I can't find it but if anyone's bored it's interesting.

siempre595

This is not the article I was thinking of, but this does help answer the question:

https://omicsonline.org/correlation-between-endometrial-thickness-and-ivf-outcome-in-an-african-population-2161-0932.1000119.pdf

They found that a lining over 13 did worse, and cite other studies where a lining over 14 does worse.  Under 8 does quite poorly.  I think the sweet spot is 8-12? But obviously people will get pregnant outside those boundaries, it will just be less common.

molly84

Thank you so much for the article! I understand a lot better now. I guess I was confused because I thought progesterone thickened the lining, but it makes me feel better knowing that I was on it to better the lining. That makes a lot more sense to me. When I asked the nurse what the progesterone was for she told me that it "gives you a nice thick lining" so I misinterpreted that. I knew someone here would have an answer for me. Thanks!! : )