The medical community dates pregnancy to the first day of a woman’s last period, even though fertilization usually occurs two weeks later. This is a long-standing but confusing practice.
Nikola Stojadinovic/Getty Images
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Nikola Stojadinovic/Getty Images
The medical community dates pregnancy to the first day of a woman’s last period, even though fertilization usually occurs two weeks later. This is a long-standing but confusing practice.
Nikola Stojadinovic/Getty Images
Florida’s ban on abortion after six weeks of gestation has been in effect since May 1. This means that the time a person has to decide whether or not to have an abortion in Florida is – at most – two weeks.
What?
It has to do with how the medical community dates a pregnancy. Here is the offer:
- A pregnancy is measured from the first day of a woman’s last period, or LMP.
- During the first two of these six weeks – before ovulation – there is no pregnancy.
- Ovulation, sexual intercourse, and conception should usually occur about two weeks after the first day of LMP.
- It takes about a week between the time an egg is fertilized and it implants in the uterus.
- It takes another week before there is enough specialized pregnancy hormone in a person’s urine for a home pregnancy test to become positive. This is also about the time when the absence of a period can indicate to a woman that she might be pregnant.
- All of the above is true for people with regular menstrual cycles. For many women with irregular cycles, it may take longer to diagnose a pregnancy.
So a six-week limit on abortion is actually a limit of four weeks after conception, and one or two weeks after a person learns they are pregnant. There are many variations in these biological standards from person to person and even from month to month.
Florida’s six-week ban has exceptions if the pregnant patient’s life or a “major bodily function” is in danger, in cases of rape or if the fetus has a “fatal fetal abnormality.”
The six-week limit on abortion is not common – it is currently in effect in South Carolina and Georgia. Many other states ban abortion altogether.
The first six-week ban came into force before Roe v. Wade was canceled in September 2021 in Texas. This was a ban on abortion after a “heartbeat” could be detected. Doctors have emphasized that there is no fetal heart at six weeks of gestation, but heart activity begins at this stage of development.
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