Progesterone: Luteal Phase Deficiency
If you haven’t read part one of the progesterone blog. Click here where I discuss what progesterone is and why it’s important. Now we are discussing luteal phase deficiency also known as luteal phase defect or a short luteal phase which is an abnormality in your cycle. I actually did a lot of my research on this topic, so I am very passionate about it.
What is a luteal phase deficiency?
A luteal phase deficiency means something is off and the timing between the development inside the uterus does not match up with what’s happening at the ovary level. This could be an abnormal response to ovulation or an abnormal endometrial growth. Common clinical symptoms are spotting or a short luteal phase. The normal luteal phase is about twelve to fourteen days in length. So what we see is that a woman ovulates and is tracking her cycle, but she starts to notice that her luteal phase is only eight or nine days. This is too short and means there is some abnormal response to progesterone, and we worry that the shift in the implantation window does not match up where the embryo is. Could there be a higher risk of infertility or miscarriage?
Some people just give progesterone supplements in the luteal phase and try to prolong it, which in fact it will because it’s the drop in progesterone that stimulates you to have a bleed. So if you are taking progesterone pills in the second half of the cycle, you won’t get a period on time. That doesn’t mean you are pregnant, and you must instruct patients to take a pregnancy test in order to know. If it is negative, you stop the pills and then you will see progesterone drop and a bleed. However, most fertility doctors, including myself, believe the true problem in luteal phase deficiency is ovulation. Luteal phase deficiency is on the spectrum of ovulation disorders. If you do not ovulate your best follicle, perhaps that follicle which is the base for the corpus luteum isn’t strong enough to make enough progesterone from it. So it’s not particularly that the brain is not sending out the right signal or that the uterus isn’t responding well. It’s that the corpus luteum itself doesn’t have the same potential.
What are the treatments?
Luteal phase deficiency can be overcome with medication to induce ovulation, just like PCOS. They are very different diseases with different symptoms. However, you can use similar treatments because in both cases you are trying to get a better egg to ovulate and have a functional corpus luteum. You can also do ovulation induction alone without supplemental progesterone. A lot of fertility doctors do both because progesterone is on the cheap end of fertility treatments and you are covering both bases. A luteal phase defect is a shortening of the luteal phase and may have fertility implications.
Recurrent Pregnancy Loss
Research is often looking at how we can help women who have recurrent pregnancy loss. They are trying to figure out if low progesterone is part of the problem. Let’s think back to progesterone. Remember that the corpus luteum gets rescued by the pregnancy? So there is a big “chicken and egg” hypothosis. If the pregnancy is genetically abnormal, it usually doesn’t make the same levels of HCG as a normal pregnancy thus it does not stimulate the corpus luteum in the same way. So there is a lower progesterone level allowing you to miscarry the abnormal pregnancy. Some evidence shows that some women may just make less progesterone. Maybe it was from that corpus luteum that didn’t function as well. Therefore could you lose or miscarry a normal pregnancy on the basis of low progesterone. In studies looking at recurrent miscarriage, it appears there is some benefit in luteal phase progesterone supplementation. Supplementation should take place after ovulation before implantation. This is a treatment commonly done for those with recurrent miscarriage (**need to start after ovulation and not with a positive pregnancy test in order to see the highest benefit).
Types of progesterone supplementation
At this time we can give oral medication, suppositories in your vagina, or an injectable intramuscular shot as part of fertility treatments. For contraception or protection of the endometrium, you can take combined oral contraception, a progesterone only pill, an IUD with progesterone, a shot of depo which is long acting, or an implant that makes progesterone. For fertility, we want things that are short lasting. Oral progesterone pills tend to make people not feel great at the level we are talking about for fertility treatments. Bloating, lethargy, and fatigue are a few of the symptoms which are definitely not most people’s favorite symptoms. So we tend to do vaginal suppositories because you get nice high levels with less symptoms, and this is because you are closer to the uterus. In treatments where your body is making some progesterone like while you are taking ovulation induction medications, you have your own natural corpus luteum, you are in a cycle where multiple follicles are stimulated or a modified embryo transfer, you are a candidate for vaginal supplementation. In this case you just need a boost. When your corpus luteum is removed from your body when you are pregnant or you are doing a controlled or medicated embryo transfer, you will need progesterone replacement. In this case you will have injectable inter muscular progesterone shots. A lot of research is looking into different ways to administer progesterone because getting a big oil-based shot in your butt everyday is not very fun. So subcutaneous fat injections with a small needle or a vaginal ring that makes progesterone are being explored in other countries. We will likely see that be introduced in the U.S. soon if it’s proven to be successful.
I want to leave you with this. If you have a hormone problem, I want you to see a hormone specialist. That is me or one of my colleagues that are all over the country. I am so upset for everyone who is trying to get help or educating themselves and are given false information. You deserve to understand your body. I am here to help you do that.
