Understanding the Luteal Phase
First, it is necessary to appreciate the meaning of the follicular phase as well. The menstrual cycle is divided into two phases: the follicular phase and the luteal phase. During the follicular phase, the follicle is stimulated to grow, releasing estrogen, while the egg within it matures. Then at ovulation, the mature egg is released and the luteal phase begins.
The term ‘luteal phase is got from the Corpus luteum or yellow body in Latin. The luteal phase is the time period between the time a woman ovulates and the time when she sees the next menstruation. The corpus luteum produces a hormone called the progesterone. The body uses the progesterone to ripen the endometrium (uterine lining). Progesterone helps prepare the ‘baby manger’ as it were, making it a comfy cushion in which the fertilized egg will be implanted and an environment within which the baby can grow.
The ripening of the uterine lining will always happens every cycle after an egg is released, this is regardless of whether or not the egg is fertilized. If the egg is not fertilized, the corpus luteum will cease producing progesterone, the endometrial lining is shed through the vagina, and menstruation begins. If pregnancy occurs, the production of progesterone from the corpus luteum continues for 7 weeks as the luteinizing hormone (LH) is released from the pituitary gland. Thereafter, the placenta takes over the duty of producing progesterone
Generally, the range of luteal phases is usually between 12 – 14 days. The length and quality of your luteal phase is one of the determinants of your fertility. If your luteal phase is very short (e.g. less than 10 days), it means that if the corpus luteum stops producing progesterone, after 9 days for instance, the home made for the fertilized egg will dislodge from the uterine wall and menstruation will begin before the fertilized egg ever gets a chance to make it from the fallopian tube, where fertilization occurs, to the uterus, where gestation happens. This may affect your chances of becoming pregnant and/or staying pregnant. Also, one may have a luteal phase of normal duration but produces less than adequate amount of progesterone to properly ripen the endometrium, in this case, there will not be an optimum environment for the fertilized egg to thrive.
If you are ‘trying to conceive’, you need to know about your luteal phase and you also need to chart your cycle, book keeping?…yes
The luteal phase helps to calculate the time of ovulation using a simple formula:
Duration of ovulation = Duration of menstrual cycle – Duration of Luteal Phase. e.g. if your cycle lasts 28 days and your luteal phase is 14 days; then the ovulation will occur on the 14th day of your cycle [28-14=14].
To determine your most fertile days, and your estimated due date when you conceive:
You can thus, plan your pregnancy by calculating the day of your ovulation.
Causes of Luteal Phase Defect
When ovaries don’t release enough progesterone
When the uterine lining is not responsive to the released hormone.
Health conditions such as endometriosis, anorexia, hyperproplactinemia, polysystic ovary syndrome, thyroid disorders, obesity.