Ovulation To Early Pregnancy: A Week By Week Cycle Tutorial: Part 1
Trying to conceive can be stressful for many couples. There is a ton of information on the Internet that can overwhelm you and make things confusing. The goal of this five-part article is to give you an in-depth analysis of the menstrual cycle on a week-by-week basis. We will start on the first day of your menstrual cycle and work our way up to pregnancy over this five-part series. We also discussed the symptoms of pregnancy and the growth of your baby in the first trimester.
Understanding your menstrual cycle and fertility window is perhaps one of the most important things to do if you’re trying to conceive. There is a lot of information that we need to cover, so sit back and let’s begin.
Week One: Your Menstrual Cycle & Menstruation
The first day of your menstrual cycle is the day that menstruation occurs and you see any blood. The duration of the menstrual phase can last anywhere between three to seven days. Many women experience different symptoms during this time of the menstrual cycle. Some of the common symptoms include fatigue, cramps, irritable moods, and even headaches. Some women are also known to experience migraines during the menstrual phase.
Menstruation occurs because the inner lining of your uterus, known as the endometrium, is being shed by your body. Leading up to the menstrual phase, your body is preparing to receive an embryo for implantation. During this ‘building up’ stage, the uterus’s endometrium lining thickens under the influence of hormones such as estrogen and progesterone. A rich network of blood capillaries and mucus glands are developed in the endometrium to make the uterus a conducive place for the incoming embryo. If you don’t get pregnant, this endometrium is shared during the menstrual phase of the cycle. Charting your cycle can give you great insights to assist in getting pregnant faster.
Why does menstruation take place?
During the first part of your menstrual cycle, your body is getting ready to implant the embryo in the uterus. During this time, estrogen and progesterone cause the endometrial lining of the uterus to grow and develop. If pregnancy is not achieved, there is a sharp decline in both estrogen and progesterone levels. The endometrium cannot survive without a healthy amount of these hormones. As these hormones decline, the endometrium becomes unstable and is shed, resulting in menstruation. Having your period is a clear sign that you did not get pregnant in the previous cycle.
It is interesting to note that your body has already started building up the process even while you are undergoing menstruation. Hormones such as FSH and LH have already begun to lay the foundation of the subsequent cycle while you are menstruating.
The menstrual cycle is dynamic, meaning the events in the menstrual cycle are continuous and not sequential. The sharp decline in estrogen and progesterone triggers hormones such as gonadotrophin-releasing hormone and FSH. These hormones start building up the endometrium lining and prepare the ovaries for ovulation. FSH stimulates the ovaries and helps ovarian follicles to mature. At any given time, as many as 30 ovarian follicles start measuring.
Week Two: From Follicular To Ovulation Phase
Your body has already started to lay the foundation of your next menstrual cycle while you are still menstruating. During week two of your menstrual cycle, gonadotropin-releasing hormone and FSH secretion are triggered. The ovarian follicles begin the process of maturation under the influence of these hormones.
During the first week of your cycle, the FSH level in your body is pretty high, which falls rapidly during the second week of your cycle. Of the 30 odd follicles that had begun the process of maturation, only one becomes dominant and completes the maturation process. The remaining follicles die off. As the dominant follicle keeps developing, it starts to release another key, the productive hormone called estrogen.
Estrogen plays several roles during this ovulatory phase of the menstrual cycle. Under the influence of estrogen, the endometrium starts the rebuilding process. Just after your menstruation, the thickness of the endometrium is about a few millimetres; however, as the follicular phase progresses, the endometrium rebuilds and can become up to 10 mm thick. A thick endometrium is necessary for the implantation of the embryo. If the endometrial lining is unable to build itself during this phase, the environment in the uterus can become hostile toward the embryo.
Oestrogen also causes the secretion of mucus from cervical cells. The mucus helps the sperm to move to the fallopian tube during the fertilization process; this mucus is referred to as egg white cervical mucus. Another important function of estrogen is to trigger the release of the Luteinizing Hormone (LH) from the pituitary gland. The increased estrogen level is sensed by the pituitary, which releases LH as a part of a positive feedback mechanism. The amount of LH increases steadily during the latter part of the follicular phase leading up to the ovulatory phase.
LH also plays many roles like estrogen; it facilitates the follicles to mature and develop fluid in the ovarian follicle. LH also causes the surface of the ovarian follicle to break down. Ovulation occurs when the follicle ruptures and releases the egg outside the ovaries. Ovulation occurs due to a sudden increase in the LH called LH surge. Most ovulation predictor kits determine the level of LH in the body to predict exactly when you are going to ovulate.
In this part, we have covered the first two phases of the menstrual cycle: the follicular and ovulatory phases. For many women, these two phases of the menstrual cycle can typically last for about two weeks. Ovulation occurs roughly on the 14th-15th day. However, you must remember that each woman is different, and your ovulation time can significantly vary according to the length of your cycle.
Fertility charting is a great way to predict your ovulation window. As your cycle can be significantly longer or shorter than the assumed 28-day period, only charting can give you a clear idea about what is happening with your body. We recommend using an ovulation thermometer and OPKs to increase your chances of conceiving.
In the next parts of the series, we will go over the next phases of the menstrual cycle, beginning at ovulation.
Fertility2Family Five Part series
Part One: Ovulation To Early Pregnancy A Week By Week Cycle
Part Two: Ovulation to Conception and Fertilization of the Ovum
Part Three: Implantation, Progesterone, hCG Tests, & the Luteal Phase
Part Four: Pregnancy Symptoms, Morning Sickness & Fatigue
Part Five: First Trimester Pregnancy Signs