What to Expect During Pregnancy Week 1

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Your last period has just started and you may be considering a pregnancy. Preconceptional health planning is a good idea. However, if you haven't started before now, make sure that you "act pregnant" until you know otherwise. Taking a prenatal vitamin, with 0.4 mg of folic acid (to help prevent neural tube defects) is a good idea. Discontinuing any form of chemical birth control, and avoiding other chemicals such as: alcohol, tobacco (even second-hand smoke), x-rays, over the counter medications, and even discussing the prescription medications you are currently taking.


As the uterus sheds its lining, the hormones are preparing another egg for release (called ovulation). This hormonal preparation is important to the health of the pregnancy and baby-to-be. So there technically isn't a baby to talk about this week, but this important prep work is helpful to the end result.


Many fathers-to-be also begin watching what they eat and drink. The health of dad does play an important role in baby's health and development. Now is the ideal time to stop smoking, develop some better eating habits and other healthful goals. More and more research is showing that the health of dad prior to conceiving is very important for the health of the baby.

Twin Tips

Early pregnancy ultrasound can usually diagnose multiple gestational sacs, and thereby you know early on. However, early ultrasound can also miss an early multiple gestation. Some reports say that the appearance of sacs via ultrasound can be different by up to 4 days.

Early ultrasound is also more helpful in determining how many sacs are present and whether or not your babies share the same sac (monoamniotic). Monoamniotic sacs occur only in identical babies and place the pregnancy at a higher risk for problems like cord entanglement.

Suggested Reading

Taking Charge of Your Fertility by Toni Wenschler

An excellent resource for anyone trying to achieve or avoid a pregnancy, it can even tell you when you are pregnant! Better than a pregnancy test and more accurate than an ovulation prediction kit, it includes great pictures, stories, and charts!

A Note About Weeks

It is standard practice in obstetrical care to calculate the number of weeks of pregnancy from the first day of your last period.