Your Menstrual Cycle: Ovulation

The most important aspect of your cycle if you’re trying to get pregnant is to identify when you are ovulating. This will help determine your “fertile window”, or the days when fertilization is most likely to occur. Because sperm can survive for 5 days, and the egg can be fertilized for 24 hours after it has been released, this window is typically 6 days long, with your most fertile day typically being 2 days before ovulation.
 

Your follicular phase of your menstrual cycle starts with day 1 of your period. At the beginning of the follicular phase, your brain releases a hormone called FSH (follicle stimulating hormone), which stimulates your ovaries to produce several follicles. As these follicles grow, eventually one becomes dominant, and the others will wither away and become reabsorbed by the body. The dominant follicle with the ripening egg increases production of estrogen, which causes the uterine lining to grow and thicken over the next 2 weeks. This rise in estrogen will cause a spike in another hormone, luteinizing hormone (LH), which triggers the rupture of the dominant follicle – ie ovulation! 

 The egg then travels down the fallopian tube towards the uterus. A structure called the corpus luteum forms in the ovary where the egg just left, which secretes progesterone - the dominant hormone in the next phase of our cycle. 

If there is sperm present, this is when fertilization might occur. The egg and sperm then travel down to the uterus and implant in the uterine lining. 

If there is no fertilization, the egg travels to the uterus, and the corpus luteum stops secreting progesterone around 9 days post ovulation, causing hormone levels to decrease, and the uterine lining to shed = your period!

How do you find out if, and when, you are ovulating?

1. CHANGE IN CERVICAL MUCUS

The most common physical sign of pending ovulation is a change in cervical mucus. The purpose of this cervical mucus is to keep sperm alive and direct it to where it needs to go. In fact, your most fertile day is likely the day you notice the most abundant cervical mucus, regardless of where you think you are in your cycle.

Leading up to ovulation, the increase in estrogen makes cervical mucus clear, and stretchy - it is often compared to a raw egg white consistency. You might notice this cervical mucus after going to the bathroom, or you might see it in your underwear. You may notice a small amount of spotting (dark brown or pinkish blood) mixed with your cervical mucus. After ovulation, when progesterone levels increase, cervical mucus becomes more sticky and often dries up. 

If you don’t notice much cervical mucus, it could be that you need to do an internal exam to better assess your cervical mucus. Drinking more water will also help increase your quantity and quality of cervical mucus! Additional supports like N-Acetyl-Cysteine can be also be used in some cases to increase the quality of cervical mucus.

2. OVULATION PREDICTOR KITS

There are many commercially available ovulation predictor kits, which detect the LH surge in your urine, which occurs about 12-36 hours before ovulation. When you think you see a positive test, you can use an app like Premom to take a picture and it will confirm if it is a positive. Once you see a positive, this is a good time to plan to have sex.

Some things to consider:
These tests can be useful, but some people have a very narrow LH surge, which is easily missed unless you are testing your urine twice a day. In certain conditions, such as polycystic ovarian syndrome and perimenopause, LH levels are more consistently elevated, so it might be hard to detect the surge. Hydration will also impact the accuracy of these results, so make sure your urine isn’t too dilute at the time of testing.

3. BODY TEMPERATURE 

Another common method for detecting ovulation is by recording your body temperature every morning before getting out of bed. Before ovulation, your body temperature is about 0.3-1 degree cooler than after ovulation. After ovulation your body temperature will increase, and will stay elevated until your menstrual cycle. This is due to the increase in progesterone, which causes an increase in body temperature. In some women, there is a noticeable dip in temperature on the day of ovulation. If you want to get fancy with temp tracking, check out this app.

Although this is a good method in theory, so many factors affect your body temperature – most notably when you went to bed, what time you woke up, the ambient temperature, sleeping in a different environment, exercising, alcohol intake etc. which can make this method a bit frustrating.

In terms of fertility, this will help confirm that you have ovulated, but once you see a temperature rise, your fertile window is already over.

4. BLOOD TEST

Testing your serum progesterone 1 week after you think you ovulated will confirm whether or not you did ovulate. In order for ovulation to occur, your progesterone level at this time in your cycle should be > 9.5nmol/L (3ng/mL). For fertility, mid-luteal progesterone levels should be at least 30nmol/L (10ng/mL).

5. ULTRASOUND

Transvaginal ultrasounds can also identify impending ovulation by measuring the size of the dominant follicle, and noting it’s reduction in size and/or change in density. This type of monitoring is typically only done in fertility clinics under the guidance of a reproductive endocrinologist, and can help time intercourse or insemination.

What if I’m not ovulating regularly?

Many factors can cause delayed ovulation, or missed ovulation (also known as anovulation). If this happens once in a while, it is not a big deal, but if it happens more often, you may want to talk to your Doctor or Naturopathic Doctor. 

Common causes of an occasional missed or delayed ovulation include stress, over-exercising or poor eating habits. Age can also be a factor in regular ovulation. Both young and older women are more likely to have a cycle that is anovulatory.  

Certain supplements and medications can also impair or delay ovulation, most commonly marijuana and frequent use of anti-inflammatory medications such as Advil. 

The most common reason for anovulation is a condition called polycystic ovarian syndrome (PCOS). In this condition, women often don’t ovulate regularly which results in very long, or absent, cycles. There are several different causes of PCOS, but the most common cause is linked to higher levels of insulin, which in turn signal the ovarian theca cells to secrete higher levels of testosterone, which then suppresses ovulation. Other common symptoms of PCOS might be weight gain, acne, hair loss, or excess hair growth on your face.

Other hormonal factors can delay ovulation, such as thyroid conditions and elevated prolactin levels.

If you suspect you may have a hormonal imbalance these can often be identified through blood tests.

Make an appointment if you would like to learn more about your fertility and how Naturopathic Medicine can help.