Month 1 (weeks 1-4)
In terms of your baby's development this period is spectacular – from just a couple of cells your baby will become a tiny human being with everything in place and ready to grow in just a couple of months. Amazing! Find out when your baby will develop things like toes, fingers, eyelids and ears, not to mention the all important heart, brain and spinal cord. Also read about morning sickness, fluctuating emotions, growing breasts (yes pregnancy is not all bad), tiredness and when to start thinking about your first antenatal check-up.
Conception & Weeks 1-2
Congratulations on your decision to have a baby! Your most fertile time of the month is when you ovulate, which is approximately 14 days after the first day of your last period if your cycles are regular. Read up on other ways to tell when you're ovulating here. Once the egg is released from the ovary, it can survive for up to 24 hours inside your body; because sperm can typically live for 5 days within a woman's body, the fertile interval therefore begins 5 days before ovulation. The highest likelihood of conception is when intercourse occurs a few days prior to and on the day of ovulation. Don't let that stop you from practicing outside of this time frame of course!
If your period is late, it's time to test - more than 80% of women will have a positive urine pregnancy test one day after the expected menses, and almost all will have a positive test 1 week after the expected menses. You can find pregnancy tests in the supermarket or just ask your pharmacist for one! A quick look at our Pregnancy & Birth Chinese Vocab sheet reveals that pregnancy test in Chinese is 试孕纸 or shìyùnzhǐ – what could be easier to pronounce?
If you're lucky to spot that wonderful sign of life when you do finally get your hands (and urine) on a pregnancy test, your estimated due date (EDD) is 40 weeks after the first day of your last menstrual cycle. Wait? Isn't that 4 weeks ago already? That's right – by the time you get round to testing, you are at least 4 weeks pregnant already, hurrah! Only 36 weeks to go and counting…
Once the sperm penetrates the egg, it is considered fertilized and becomes a zygote (cool name huh? Not an alien spaceship then…). The zygote has 46 chromosomes, 23 from mom and 23 from dad, which determine the baby's genetic make up – imagine half of you and half of your partner running around... cute!
After fertilization, the zygote travels down the fallopian tube toward the uterus, rapidly dividing into lots of cells that already now are forming into groups: the inner group of cells will become the embryo (= your baba), and the outer group will become the membranes and placenta that support and protect it.
It can take up to 48 hours before this cluster of cells (about 50 to 60 and multiplying rapidly), or blastocyst (another name already??), attaches to the inside of the uterus. This process of attachment is called implantation. Implantation normally occurs 5 to 8 days after fertilization, so three weeks approximately after the first day of your last period. This is also when IVF (in vitro fertilization) embryos are normally transferred into the uterus – three weeks into your pregnancy and you and your baba finally get to connect!
Following implantation, the placenta (= baby's round the clock Sherpa's home delivery service), also starts to form. This lovely thing called Human Gonadotropin Hormone (hCG) is then released, responsible for those wonderful early pregnancy symptoms such as nausea and breast tenderness. It's this same hormone that is detectable in pregnancy tests so we'll forgive it for bringing us some good news too.
At the end of week 4 the embryo measures approximately 2-5 millimeters – wow!
The medical information and images contained in this calendar were provided by Nichole Mahnert, an American-trained Ob/Gyn currently practicing in Shanghai. The calendar was co-authored by our Managing Editor, Ellen Swabey.