Six weeks of pregnancy is a cutoff based on when embryonic cardiac activity can often be detected. This electrical cardiac activity, however, does not equate to separate, individual survivability. It's simply a physiologic, embryological step.
Six weeks is very early in a pregnancy. Women with conditions like PCOS who have unpredictable timing of their periods, women who experience implantation bleeding and assume it is a period, women who have no periods in the setting of use of hormonal contraceptives but unfortunately experience failure of the contraceptive, and many other women often do not know they are pregnant at this point.
The safety of pregnancy termination has repeatedly been shown. Early pregnancy termination is often successful with medication alone and no surgical procedure. The risks are low, especially when compared to the risks of pregnancy that exist even for a woman who is in good health at the onset of a pregnancy. Pregnancy is not a stage that women typically want to or should enter under suboptimal conditions. The field of obstetrics and the further specialization of maternal-fetal medicine exist for a reason: things can go wrong. I always tell my patients with high risk situations that we will "prepare for the worst and expect the best". The OB side of my job is, for the most part, joyous. However, when it is bad, it is terrible. Again, risks exist in pregnancy even for previously healthy women. There are women with significant medical conditions that make pregnancy highly life-threatening.
At 6 weeks, we know nothing about the fetus itself. The first available genetic testing can be done around 10 weeks. An ultrasound assessing full anatomy is typically performed around 20 weeks, at which point sometimes severe fetal anomalies incompatible with life are first noted.
Barriers to clinic-based abortion services lead women to unsafe alternatives. Abortion existed prior to the passage of Roe v Wade, but it was often pursued by secretive, dangerous means. Many women required hospitalization for severe infections, lost their uteruses and all future childbearing potential, or died.
Included in the language of one of the recent abortion restriction bills is that treatment for ectopic pregnancy (a life-threatening condition if not appropriately managed where the pregnancy grows outside of the uterus, usually in the fallopian tube) must include removing the pregnancy from its location and placing it in the uterus instead. They are trying to mandate into law that OB/GYNs perform a procedure that DOES NOT EXIST. Not only does this harm those who will have ectopic pregnancies in the future, but it makes people who have experienced it in the past question how their situations were managed.
The same bill directs that people who experience miscarriage could be questioned to find out if they were "at fault" and could potentially face prison time based on results of this investigation. Miscarriage can already be incredibly emotional, and it is the natural reaction for people who go through it to blame themselves. They repeatedly think over literally every action they took in the preceding weeks, when ultimately most miscarriages are a result of factors beyond personal control. This legislation would perpetuate these types of thoughts. With people who don't understand the process leading these "investigations", people may actually be punished for experiencing a loss.
People with uteruses are not just vessels for pregnancy. Their health and well-being matters.
So-called "heartbeat bills", as for most prohibitive abortion legislation, are cruel and not based in science. They are bad for women, families, and communities.