However, ABC’s headline declaring these vaccines “safe and effective” for pregnant women seems a bit, er, premature. The size of these studies might be reason to hold off on adding this to gender-reveal parties:

The Pfizer and Moderna vaccines are safe and effective in pregnant and lactating women and those women are able to pass protective antibodies to their newborns, according to a new study.

To come to that conclusion, researchers studied a group of 131 reproductive-age women who received the Pfizer or Moderna vaccine, including 84 pregnant, 31 lactating and 16 non-pregnant women and found antibody levels were similar in all three groups.

A study size of 131 subjects is nowhere near large enough to reach these kinds of conclusions. That’s especially true when partnered up with a control group of only sixteen women. That looks like a Phase 1 study at best, and more likely an uncontrolled subset of some other study. The FDA is going to want a much more robust sample and a balanced double-blind study before it issues an EUA for vaccinating pregnant women.

Assuming this holds up, however, the potential coverage in expanding vaccinations looks huge. The COVID-19 virus is blessedly not terribly effective in small children, but newborn immune systems are unusually susceptible, as every panicky parent knows. The mRNA vaccines might give these newborns a significant head start, either by passing immunity through the placenta or through breast feeding after birth:

Another common concern among pregnant patients is vaccine side effects. The study found no significant difference in vaccine side effects between pregnant and non-pregnant study participants.

Compared to pregnant women who had recovered from COVID, pregnant women who received the vaccine had “strikingly higher” antibody levels. Interestingly, women who received the Moderna version had greater antibody levels than those who received the Pfizer. Vaccine-generated antibodies were present in all of the umbilical cord and breast milk samples that were tested, which suggests that pregnant and lactating women pass COVID-19 protection to their fetuses or newborns.

The value of rapidly confirming the safety and efficacy is obvious. If pregnant women pass immunity on to their newborns, those children can either avoid an inoculation for a while or perhaps forever. Older children are already being studied for their responses to the vaccine. We might have the loop fully closed on age-group vaccinations by the end of the year if we can get those “two-fers” now.

One has to wonder how many pregnant women may already be getting vaccines, either because they don’t yet know they’re pregnant or because they’ve decided to take the vaccine anyway. That may not be much of an issue at the moment with most states restricting access to age groups generally above the fertility years, but that’s changing — rapidly. More than half the states will offer vaccines to all adults by the beginning of next week, including Minnesota, which joined the club today:

The COVID-19 vaccine will be available to all Minnesotans 16 and older beginning Tuesday, Gov. Tim Walz announced Friday morning.

A statement from the governor’s office said Minnesota’s most critical goal is getting “as many Minnesotans vaccinated as quickly as possible to end this pandemic,” which is showing signs of increased activity in the state again.

“Minnesotans have done a remarkable job helping our most vulnerable get vaccinated and waiting their turn,” Walz said in a statement prepared ahead of a live video address at 11:30 a.m. “Now, as we prepare to receive more vaccine heading into April, it’s time for all Minnesotans to get in line.”

The expanded eligibility means another 1.2  million Minnesotans will be added to the pool of state residents seeking protection from the novel coronavirus that causes COVID-19.

The state has struggled at times with supply, but apparently that’s not going to be a problem from here on out. Walz joins several other governors who seem confident enough in supply chains to open up availability to everyone, which will unleash a lot of pent-up demand. It also dispenses with “equity” rationing in favor of a fully open system, which should have been the approach all along.

In terms of the ABC report, it might produce high demand among pregnant women, especially if they see this report and assume that this is a medical certainty. There’s no reason to think these vaccines would be harmful, but it’s too early to say that their safety has been proven yet, at least not with the numbers stated in ABC’s coverage. The manufacturers might end up with a lot more study cases by default anyway.

Update: Updated headline and second paragraph for better clarity.