Believe it or not, your pregnancy journey begins now, even though you’re not actually pregnant yet. That’s because most practitioners start timing pregnancy based on the first day of your last menstrual period (LMP).
In weeks 1 and 2 of pregnancy, your body is gearing up for ovulation and preparing for fertilization, which will happen in week 3.
Your Baby at Weeks 1 and 2
This week the groundwork is laid for the big O — ovulation — the all important first step toward the making of the baby of your dreams. And like those dreams, the baby action is all in your head right now — where the hypothalamus, the control center in your brain, works with its partner in reproduction, the pituitary gland, to start releasing hormones.
These hormones — called FSH and LH — prompt the ovaries to get cracking on some eggs, ripening one to maturity within its follicle. All this egg action causes the ovaries to crank up production of two other powerful hormones, estrogen and progesterone. These hormones, the dynamic duo of the reproductive system, get the reproductive party in your uterus started, telling the uterus to thicken its lining, forming a blood-pumped cushion in anticipation of hosting a fertilized egg.
Midway through your menstrual cycle — around day 14 if you have an average 28-day cycle — the dominant follicle in the ovary swells and then ruptures, releasing the mature egg of the month. That egg, the one with your baby’s name on it, bursts through the walls of the ovary and is immediately swept up into the fringed opening of the fallopian tube, where it will take a six day odyssey down to the uterus. Ovulation has just occurred.
Meanwhile, swimming along as fast as their little tails can flutter, millions of sperm are making a beeline for that egg, up through the cervix, into the uterus, and then on to the fallopian tube. One especially persistent suitor survives the grueling journey to intercept the egg and burrow into its outer layers. The victorious sperm plunges into the egg’s nucleus, releases its own genetic contribution, and bingo! the egg is officially fertilized. That twinkle in your eyes is about to become…a baby.
At a Glance
1 to 2 weeks pregnant is how many months?
If you’re 1 and 2 weeks pregnant, you're in month 1 of your pregnancy. Only 8 months to go! Still have questions? Here's some more information on how weeks, months and trimesters are broken down in pregnancy.
Gearing up to ovulate
No, there’s no baby or embryo in sight. At least not yet — just an anxious egg and a whole bunch of eager sperm at their respective starting gates.
But in weeks 1 and 2 of pregnancy — the week of and immediately following your last menstrual period — your body is working hard to gear up for the event that paves the way for baby: the big O, or ovulation.
Right now, your uterus has begun preparing for the arrival of a fertilized egg, though you won't know for sure if that egg has successfully matched up with sperm until next month.
Calculating your due date
How can you call this your first week of pregnancy if you're not even pregnant? It’s extremely hard for your practitioner to pinpoint the precise moment pregnancy begins (when sperm meets egg).
While there’s no mistaking the start of your period, the exact day of ovulation can be hard to nail down. What’s more, sperm from your partner can hang out in your body for several days before your egg comes out to greet it. Likewise, your egg can be kept waiting for up to 24 hours for late sperm to make their appearance.
So in order to give all pregnancies some standard timing, most practitioners use the first day of your last menstrual period as the starting line of your 40-week pregnancy. Still confused? Think of it as a head start — you're clocking in roughly two weeks of pregnancy before you even conceive!
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