Week 2
There is still no baby this week, only an egg getting ready. Inside one of your ovaries, a single follicle pulls ahead of the others and swells with fluid around its egg. Rising estrogen thickens the lining of your uterus, and near the end of the week a surge of hormone triggers ovulation. Counting from your last period, conception usually happens around the end of this week or early next week. The embryo's own clock starts then, about two weeks behind the numbers in this book.
This is a week for clearing the way. Alcohol, smoking, vaping, and cannabis all affect a pregnancy from its earliest days, so now is the time to stop. It is also a good week to learn the signs of ovulation and how the fertile window works.
Figure 3. A typical 28-day cycle, from the first day of your period to the day a test can turn positive.
Day 8 · 1 week 0 days
One egg is pulling ahead of the rest
Earlier this cycle, several follicles began to grow in your ovaries. By now, one of them has usually become dominant. It grows faster, makes more estrogen, and the others quietly stop developing. In most cycles, only one egg will be released.
The dominant follicle keeps growing until it is about 2 cm across, large enough to see on an ultrasound. Inside, the egg is finishing an important step. It is completing a special cell division that halves its chromosomes, so that it will carry 23 rather than 46. The other 23 will come from a sperm.
Meanwhile, estrogen from the follicle is doing two jobs. It rebuilds the lining of your uterus, making it thicker and richer in blood vessels. It also changes the mucus at the cervix, making it thinner and more slippery so sperm can travel through it more easily.
Sometimes two follicles mature and release an egg each. If both are fertilized, the result is fraternal twins. This is more likely with age, with a family history on the side of the person ovulating, and with some fertility treatments.
Try this: Notice how you feel physically through this part of your cycle. Many people find their energy and mood are at their best in these days.
Day 9 · 1 week 1 day
No amount of alcohol is known to be safe
Alcohol passes freely through the placenta. A developing baby cannot process it the way an adult can, and it can affect growth and brain development at any stage of pregnancy. The effects range from subtle learning and behaviour difficulties to fetal alcohol spectrum disorder, a lifelong condition.
There is no known safe amount, no safe type of drink, and no safe time. Wine and beer are not gentler than spirits. The simplest and safest choice, recommended by major health bodies, is not to drink at all while trying to conceive and throughout pregnancy.
Many people drink before they know they are pregnant. If that was you, try not to panic. The risk from light drinking in the very early weeks is thought to be low, and stopping now is what matters most. Tell your care provider honestly. They hear this often and will not judge you. If you find it hard to stop, you are not alone, and help works. Your care provider can connect you with support that is confidential and focused on you and your baby.
Social situations can be the hardest part. Having an alcohol-free drink you actually enjoy makes it easier to say "no thanks" without explaining. Try this: Pick one or two alcohol-free drinks you like, such as sparkling water with lime or a non-alcoholic beer, and keep some at home.
Day 10 · 1 week 2 days
Stopping smoking is one of the best gifts you can give
Smoking in pregnancy reduces the oxygen reaching your baby. It raises the risk of miscarriage, ectopic pregnancy, problems with the placenta, preterm birth, low birth weight, stillbirth, and sudden infant death. It can also make it harder to conceive in the first place.
The good news is that stopping helps at any point, and the sooner the better. Within days, carbon monoxide levels in your blood fall and more oxygen reaches the baby.
Vaping is often seen as a safer option, and it does avoid the tar and carbon monoxide in cigarette smoke. But most vapes still contain nicotine, which affects a baby's developing brain and lungs, and the long-term effects of the other chemicals are not well known. The aim is to be free of nicotine and smoke altogether. If you smoke and cannot stop any other way, talk to your care provider about the options, including nicotine replacement under their guidance.
Second-hand smoke matters too. Ask the people around you not to smoke in your home or car, or near you.
Quitting is hard, and support roughly doubles your chances. Free stop-smoking services and quitlines exist in many places, and your care provider can refer you.
Try this: Look up the stop-smoking service or quitline in your area today, even if you are only thinking about it.
Day 11 · 1 week 3 days
Cannabis is best left out of pregnancy entirely
Cannabis is legal in some places, and some people see it as natural or harmless. In pregnancy, it is not. THC, the main active ingredient, crosses the placenta and reaches the developing brain. Studies link cannabis use in pregnancy with lower birth weight and possible effects on attention, memory, and behaviour in childhood.
This applies to every form: smoking, vaping, edibles, oils, and drinks. Smoking it also brings the same harmful smoke as tobacco. Products sold as CBD are not proven safe in pregnancy either, and labels are not always accurate about what they contain.
Some people use cannabis for nausea, anxiety, pain, or sleep. Those are real problems that deserve real help. Your care provider can suggest treatments that have been studied in pregnancy and are known to be safer. If you have been using cannabis regularly, stopping can cause irritability, poor sleep, and cravings for a week or two. That is withdrawal, and it passes. Tell your care provider about your use honestly. It helps them give you better care, and the conversation is confidential.
The same goes for any other recreational drugs. If you use them, now is the time to talk to someone who can help you stop safely.
Try this: If you use cannabis, write down what you use it for, then bring that list to your next appointment so you can ask about alternatives.
Day 12 · 1 week 4 days
Your body gives clues that ovulation is near
If you are trying to conceive, it helps to know the signs of ovulation. None of them is perfect, but together they paint a clear picture.
Cervical mucus is one of the most useful. In the days before ovulation, it becomes clear, slippery, and stretchy, a bit like raw egg white. That is the most fertile type. After ovulation, it turns thicker and stickier, or dries up. Ovulation predictor kits test your urine for luteinizing hormone, or LH. This hormone surges about a day or so before ovulation, and a positive test means your most fertile days are now. Kits are easy to use, though they can be less reliable for some people with polycystic ovary syndrome. Basal body temperature, your temperature on waking, rises slightly, by about 0.2 to 0.5°C, after ovulation and stays up until your next period. Because it rises after the event, it is better for confirming a pattern over a few months than for timing sex in the moment.
Some people also notice a twinge of pain on one side of the lower belly, mild breast tenderness, or a higher sex drive around this time. Try this: If you are trying, check your cervical mucus once a day this week and note what you see. A pattern usually appears within a cycle or two.
Day 13 · 1 week 5 days
The fertile window is about six days long
You can only get pregnant on a handful of days each cycle. The fertile window is roughly six days long: the five days before ovulation and the day of ovulation itself.
The reason is simple biology. Once released, an egg survives for only about 12 to 24 hours. Sperm, on the other hand, can live in the reproductive tract for up to five days when cervical mucus is welcoming. So sex in the days before ovulation gives sperm time to be waiting when the egg arrives. The two or three days just before ovulation are usually the most fertile.
There is no need to time things to the hour. Having sex every two to three days through the cycle covers the fertile window without the pressure of a schedule. Daily sex around ovulation is also fine. Sperm counts stay healthy for most people with frequent sex.
Lying still afterward, special positions, and particular foods have not been shown to make a difference. Some lubricants can slow sperm down, so if you use one, look for a product labelled as fertility-friendly. For people under 35, about 8 in 10 couples conceive within a year of regular sex without contraception. It is common for it to take several months.
Try this: If you are trying, mark your likely fertile window on a calendar based on your usual cycle length, and leave the rest of the month free of pressure.
Day 14 · 1 week 6 days
Around today, an egg may be released
In a 28-day cycle, ovulation usually happens around day 14. The LH surge causes the dominant follicle to break open and release its egg. Finger-like fringes at the end of the fallopian tube sweep the egg inside, where it begins a slow journey toward the uterus.
The egg is one of the largest cells in the body, just about visible to the naked eye. It has a short window to meet a sperm, usually within a day of release. Fertilization almost always happens in the fallopian tube, not in the uterus.
The empty follicle left behind in the ovary transforms into the corpus luteum, a small gland that makes progesterone. Progesterone keeps the uterine lining ready. If a pregnancy begins, the corpus luteum keeps working for the first weeks until the placenta takes over.
If your cycles are longer or shorter, your ovulation day shifts too. That is why your period date is only a starting point, and why an early ultrasound may later fine-tune your due date.
Trying to conceive can put a strain on a relationship. Sex on a schedule can feel more like a task than closeness, and each month brings a wait. For your partner: Keep some time this week that has nothing to do with trying, such as a walk, a meal, or a film together, so the relationship stays bigger than the calendar.