The Luteal Phase and a Possible Defect
Your menstrual cycle is in two parts namely the luteal phase and the follicular phase. The follicular phase is when a follicle is stimulated for growth. During this time the egg within it matures while the follicle releases estrogen. When you ovulate the egg is released and thus begins the luteal phase. The follicle then turns into a degenerating tissue (known as the corpus luteum) and then releases progesterone. Estrogen helps with building the endometrial lining and when combined with progesterone they create the perfect environment in the endometrium for embryo implantation.
The luteal phase lasts between 10 and 16 days and is consistent with every cycle. It goes for an average of 14 days for many women and it ends when you see your period. This period is very important if trying to conceive because you are most fertile for a very short time. Your fertility peaks two to three days before ovulation and for between 12 and 24 hours after you ovulate.
Luteal Phase Defect (LPD)
Sometimes things don’t go as expected and this causes a slight ‘glitch’. In this case the glitch or shortcoming is insufficient progesterone. This affects development of the endometrium and may interfere with implantation of the embryo. After all, the endometrium is where the embryo implants and gains nourishment as it grows into a baby. An underdeveloped endometrium is therefore unsuitable for implantation. A low amount of progesterone also shortens the luteal phase and causes your period to come too soon.
There has been a lot of controversy and disagreement about the existence of LPD and as a result, methods to treat it. There are however, methods that have been devised to diagnose it but most of them haven’t been able to accurately predict infertility. It is also difficult to evaluate fertility using these methods.
You would think measuring the amount of progesterone produced would give an idea as to what is going on but progesterone is released in pulses from the corpus luteum. It could therefore be high at one point and very low at another. This means that there is no single value that can be termed as normal or within range.
A proper diagnosis can’t be arrived at using a single test. Useful tests include a pregnancy test, a series of endometrial biopsies, follicle-stimulating hormone (FSH) level and luteinizing hormone (LH) level tests. You must do a pregnancy test before an endometrial biopsy because an endometrial biopsy can’t be done in pregnancy.
The purpose of the biopsy is to find out whether you are ‘in phase’ or not but the best diagnosis is derived from two or more ‘out of phase’ results. Changes can occur in the luteal phase every so often in every woman and doesn’t quite give a difference between a fertile and an infertile woman. This makes it difficult to use biopsies for routine infertility tests.
A pelvic ultrasound could be useful for diagnosis because the doctor can measure the thickness of the endometrial lining.
Luteal phase defect doesn’t quite affect the rest of your body. If anything, it could be that there are some other conditions that are causing it. If you aren’t trying to conceive it is not necessary to seek treatment.
If you are trying to conceive, your doctor may prescribe the following:
- Human chorionic gonadotropin (hCG). This will induce ovulation and help increase the production of progesterone.
- Clomiphene citrate to stimulate your ovaries into making more follicles. These follicles will then release more eggs for fertilization thus increasing your chances of conception.
- A dose of progesterone in the form of injections, suppositories or pills may be useful in supporting the growth of the endometrial lining after ovulation. It is important to note that taking progesterone after you conceive isn’t prevention against miscarriage.
Studies haven’t proved that treating LPD increases the chances of a successful pregnancy for those that don’t use assisted reproduction methods. Not all treatments will work so talk to your doctor regarding the different treatment options.