Rebecca Falnes
Senior Sonographer
If there’s one thing I’ve noticed during my years working in the medical field, it’s that the majority of women don’t understand their periods. As your period usually goes on for about 40 years of your life, it’s nice to have an understanding of what’s going on inside your body. Most women get their first period between the ages of 10-16, the average age being 12. On the other end, most women stop having periods between the ages of 45-55, the average age being 51.
Every month, whether you want it to or not, your body is preparing to get pregnant. The lining of your uterus builds up and gets thicker and thicker throughout your cycle preparing for a baby. Halfway through the cycle one of your ovaries releases an egg. If that egg gets fertilized and implants in the thickened lining of the uterus, you become pregnant! If not, then your lining has to come out – this is your period. Your uterus gets rid of all that tissue it built up for a baby, then it starts over fresh and builds up that lining to try again.
Cycle Length
A “normal” menstrual cycle is defined as lasting 28 days. This means there is approximately 28 days between when one period starts and when the next period starts, that is one cycle. However, it can also be normal for cycles to be anywhere from 21 to 40 days in length. Everyone is different and while we do our best to define a normal standard, not everyone’s body will fit into that.
Regular vs Irregular Periods
A regular menstrual cycle means that your period comes after a set amount of days, and that number of days is consistent (or only off by a day or two). So if your period comes every 28 days, you have a regular cycle that is normal in length. If your period comes every 33 days, you also have a regular cycle, just a longer one. If your period comes every 25 days, you have a regular cycle that is shorter. Again, anywhere between 21-40 days is considered normal. And if one month you have 25 days between periods and the next month is 26 or 27 days, that is still considered a regular cycle.
Irregular menstrual cycles occur when there is no consistency between when your periods come. If one month you have 25 days in your cycle and the next you have 38 days, or if you go months in between cycles, then you have an irregular period. There are a lot of factors that can cause irregular periods – hormone imbalances, excessive stress, and polycystic ovarian syndrome are some of the most common causes. Being overweight or underweight can also cause irregular periods. It’s important to note that irregular periods do not necessarily cause fertility problems, but it can make it difficult to determine the best time to try to get pregnant. It also makes it more difficult to estimate your due date when you do become pregnant, and that has to do with ovulation.
Ovulation
Each month, one of your ovaries releases an egg – this is called ovulation. They usually take turns, the right ovary ovulating one month and the left ovary ovulating the next month, but sometimes one ovary is dominant and likes to ovulate more than the other. Both ovaries contain multiple follicles, and each follicle contains an egg. At the beginning of your cycle, one follicle will start to grow larger and larger until it bursts and releases the egg inside. This usually happens around the 14th day of your cycle, or 14 days after your period started.
Sometimes this can cause pain or cramping, known as ovulation pain. This can last for a few hours or even a day or two. Some women don’t notice at all as they have no symptoms of ovulation. Other women can pinpoint exactly which ovary ovulated and when because of the pain. The important thing to note is that if you do get cramping or pain, it should go away after a day or two. If you have pain that lasts longer it may be worth mentioning to your doctor to try and figure out why.
Just like periods can vary in length, ovulation may not be exact for everyone. It may be normal for you to ovulate on day 10, or on day 20. It’s just that day 14 is when it’s considered the most common. After ovulation, there’s about a 48 hour window when fertilization is likely to occur. It is possible to get pregnant at any point in your cycle, depending on when your ovary releases the egg, but this is the best estimate. You can buy ovulation kits that can give you an idea of when you ovulate in your cycle, but those tend to be pricey.
To summarize what we’ve covered – we base your due date on the first day of your last period, but you don’t ovulate until 14 days after that and conception happens sometime after ovulation. That means for the first 2 weeks there isn’t actually an egg or a baby yet – but it’s part of your body’s cycle so it’s still counted as part of your pregnancy.
If you would like more information on anything covered in this post, you can get in touch via info@theultrasoundsuite.ie or send us a message on our Facebook page and we will get back to you as soon as possible. Our website www.theultrasoundsuite.ie also provides a wealth of information on our various policies and procedures.