Endometrium question (answered)


In “Romance Without Regret” Jason Evert points out that the Pill causes the endometrium wall to gradually become thinner.

He says that it is typically 5-13 mm thick, but can eventually become only 1 mm thick due to the effects of the Pill. The thin lining can cause the embryo to not implant well, resulting in a miscarriage.

I was wondering…1 mm is still a pretty good thickness for such a small thing to attach to. So I was going to ask about that.

Before I did, I thought I’d learn about it some. What I learned was the cells of the infant that attach to the endometrium are called the “Blastocyst.” And the Blastocyst is about 70 - 100 cells.

It may be called something different the moment implantation onto the endometrium occurs. But still…a 70-100 cell structure is implanting onto the endometrium.

The endometrial lining goes through a cycle (~28 days) and the lining grows thick as fertilization of an egg becomes possible so it will be ready for the blastocyst to implant. It grows and sheds based on hormone levels such as estrogen and progesterone.

So…I’m thinking that the Pill causes improper levels of estrogen and progesterone, which result in the endometrium not being fully regenerated when it’s supposed to be, resulting in poor environment for implantation.

Is that right??


This is also why women on the Pill often have lighter (if any) periods… there isn’t as much endometrium to shed.


Thanks Emily


Just curious…why is a single guy posing endometrium questions?


haha, good question!

No, I’m not expecting a baby, not that you were thinking that.

When I get into learning about something, I like to go into it quiet a bit. Right now it’s Theology of the Body and that eventually leads to NFP.

That, and I’ve met a wonderful woman and there is definitely potential between us. So my mind is on those types of things. Not “endometriums” of course, just that whole scope of topics.


I was guessing it might be that last bit about meeting a woman that you are interested in. Just want to say if you’ve met someone who previously was on the pill, don’t convince yourself that her womb is now inhospitable to life. I don’t know if that was what piqued your interest here or if you were looking at it more from the slant of coming up with good reasons to practice NFP. If you are worried, I can tell you as a convert to the faith and a former user of birth control pills, that I did manage 4 successful pregnancies and no known miscarriages. I do know women who have had problems conceiving and have had to receive some mysterious “treatment” in order to be able to not miscarry. So, there is some truth there, but things are not hopeless for women who have used the pill.


Very thoughtful Dulcissima, thanks for the info.


I think its great that a single guy is posting questions such as this. Our culture already makes fertility a one-sided issue. The more that both men and women understand that it is combined fertility that make a child, and the more that each sex understands the other’s bodies and the harm that can be done to them, the more they might respect them as temples of the Holy Spirit.

This goes also with the need for knowledge in order to evangelize when called upon…to anyone.

When I started NFP charting for my health (I’m single), my respect for my own body, and for God’s amazing design grew 10 fold.

Reformed Rob, the “wonderful woman” you’ve met is sure lucky to be talking with you.


And, just to add to dulcissima’s post…

I only ever used birth control pills for a short time, like, a few months out of my life. I hated the side effects, and then when I found out how they really worked, I chucked them for good. (Nice how doctors don’t tell you these things…I had to dig deep into the informational insert, and not the one intended for patients, to find out about the function that makes the uterine lining inhospitable for implantation! :mad: )

So my endometrium has been pretty much left alone to do its natural thing for the vast majority of my life. (I am 32.) And yet, last year, after four successful and uneventful pregnancies, I had two early miscarriages within six months. So there really are no guarantees. Sometimes even the most hospitable womb can’t save a life that has some kind of problem. :frowning: That is our assumption, anyway, that there were genetic problems incompatible with life in those two conceptions. Because it seems the system still works fine when it has no reason not to. I am nine months pregnant right now! :smiley:

Good luck, and I too am glad that you are looking into this before you are married. You are so far ahead of so many of us who struggle and learn AFTER marriage.


For the same reason a single women would be trying to educate herself on NFP.(believe it gets to be fun a parties when i can talk to my friends about NFP and not be dating anyone. you get the werid looks but good questions about the church teachings and such) You honestly need to know all the facts before you start dating to understand the potential discussions.

Glad to hear that you might have found a women to court. Good Luck!


Just to clarify, I wasn’t thinking that the OP was odd for asking a question on such a topic. I was really more curious if his question was based on any concerns he might have if he was in the process of getting to know someone. I agree that we should be asking these kinds of questions before we get married.


Thanks Dulcissima. I didnt’t think anything negative about your asking. To be honest, I got a laugh out of your question, so thanks for inserting some humor into my day :slight_smile:


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