A normal cycle can be broken down into three parts. For the sake of this explanation, we are going to consider a typical menstrual cycle to be 28 days long, even though it may vary by a few days on either side. Day 1 marks the first day of menstrual flow. If your period starts after 5 p.m., day 1 is officially considered the next day.
THE FOLLICULAR PHASE—This is considered day 1 to ovulation. A new follicle is recruited and develops until it reaches maturity. During this time, the uterine lining sheds the old and grows a new one in the hopes of implanting a fertilized embryo down the line.
OVULATION—The brain senses that the egg is ripe and ready to ovulate. At this stage, a surge of luteinizing hormone is sent from the brain to the ovaries, known as the LH surge (a.k.a. the happy face on some ovulation predictor kits).
Typically, the span of time between ovulation and your period takes about 14 days, so in a consistent 28-day cycle, you can usually predict that an egg will be released on approximately day 14 (with an LH surge that happens roughly 36 hours earlier).
It’s important to remember that this is only an average. While most women with regular cycles will ovulate 14 days before flow, ovulation can occur 12 to 16 days from when you expect the next menstrual period to start and still be completely normal.
THE LUTEAL PHASE—This is the time following ovulation through either the onset of the period or a positive pregnancy test. This phase is marked by an increase in basal body temperature because the body has to be warmer than usual to host a pregnancy.
In the later part of the luteal phase, you may experience PMS symptoms such as breast tenderness, acne, and mood swings. Pregnancy symptoms are quite similar to those you may experience with PMS, so unfortunately, trying to read your symptoms at this time to determine if you’re pregnant is typically futile.
Two Important Tips for Maximizing Baby-Making Potential 
Capitalizing on your unique fertile window and making sure your partner’s on his game too can go a long way in moving the odds in your favor.
If your cycle is irregular or you just want to be sure, you can estimate ovulation using one of the following methods:
OVULATION PREDICTOR KITS (OPKs) test urine for a rise in luteinizing hormone (LH), which precedes ovulation by roughly 36 hours. These kits are available over-the-counter, and while they can be pricey and sometimes unreliable, they are useful tools, nevertheless.
Some kits ask you to start monitoring right at the onset of your period, measuring hormone levels for the full two weeks prior to ovulation. We actually don’t recommend these devices. They are expensive and the results can be confusing—frankly, we think they are overkill. By the same token, the supercheap, generic pee sticks can be confusing, too.
We recommend a straightforward, digital urine test stick that lets you know (with a smiley face) when you’re in your peak fertility window. When this test is positive, you will likely ovulate within 24 to 36 hours, so time to get busy!
MONITOR CERVICAL FLUID. Just prior to ovulation, cervical fluid takes on the consistency and transparency of raw egg whites. Some women notice this easily when they wipe, while others find the change hard to detect.
For women with PCOS, monitoring cervical fluid may not be a useful method of tracking ovulation, as you may have discharge that is egg white consistency throughout the month, not just at ovulation.
CHECK CERVICAL POSITION. With a little practice, you can check the position of the cervix to determine ovulation by inserting one or two clean fingers. Right before ovulation you will find that the cervix is soft, high, and open—the better to receive sperm. During the rest of your cycle, the cervix is lower and firmer.
TRACK YOUR BASAL BODY TEMPERATURE (BBT) daily, first thing in the morning before getting out of bed. A slight rise (at least 0.4 degrees) indicates that your corpus luteum is kicking in and that ovulation has occurred.
It’s important to note that BBT charting is a great way to look at the phases of your cycle in hindsight, but not great for in-the-moment ovulation prediction. That’s because ovulation has already happened once the temperature spikes.
If you do chart, take them with you when you visit your acupuncturist. Besides predicting ovulation, in Chinese medicine we can use BBT charting for insight into your body’s core constitutional patterns.
HAVE SEX WHEN YOU’RE MOST FERTILE
Once you’ve determined your likely ovulation date, start having baby-making sex two days prior to the estimated day. Since an egg typically survives only 12 to 24 hours after being released, the fertility window ends less than a day after ovulation. That said, it is key that the sperm be waiting for the egg when it ovulates, so the true target is the day of your LH surge on a predictor kit, or starting the day your cervical mucus becomes slippery and your cervix moves forward.
After ovulation, many women report a drop in libido and less natural lubrication. Sometimes sex is also uncomfortable at this time. This is your body’s way of telling you the baby-making window is now closed.
DON’T FORGET YOUR OTHER HALF
It’s kind of a running joke among fertility specialists that if women could take a pill to improve their partners’ sperm counts, they would do so happily. For reasons yet unknown to the female species, many (certainly not all) men are resistant to changing diet and lifestyle habits for the sake of their swimmers.
Unfortunately, because sperm issues comprise at least 30 percent of fertility problems, resistant men can lead to mighty distressed damsels. So guys, if your wife or girlfriend is forcing you to read this section, please take it to heart. We know you want to have a baby, no one doubts you, but you have to show up for the party. Your better half is going to have to take on the lion’s share of this journey, even if the obstacle between you and Junior is a sperm issue. She will still be the one going through the fertility treatments, the ultrasounds, the morning sickness, stretch marks, childbirth … need we go on?
Having “unprotected” sex does not ensure a baby. Like an electrical fuse box, there is a trip switch, and while it may seem like you’re doing everything right, some couples require a bit of fine-tuning (and sometimes major rewiring) in order for sperm and egg to equal your future child.
SPERM ISSUE? TIME IT RIGHT
If you know or suspect that the future baby daddy has sperm issues, it’s best to abstain from sex for two to five days prior to the LH surge and ovulation to allow sperm to regenerate. After that, be sure to have sex on the day of the surge and at least one more time in the following 36 hours.