JOHN: TONIGHT ON PBS NEWS WEEKEND, THE TRUMP ADMINISTRATION LAYS OUT ITS VISION FOR THE U.S.

ROLE IN THE WORLD, TAKING "AMERICA FIRST" POLICIES GLOBAL.

THEN, WE EXPLORE HOW ARTIFICIAL INTELLIGENCE IS HELPING PREDICT PRE-TERM BIRTHS.

AND, THE BENEFITS AND RISKS OF AN ICY PLUNGE AS WINTERTIME OUTDOOR SWIMMING GAINS A GLOBAL FOLLOWING.

EMILIANO: IT'S REALLY REFRESHING, I THINK IT'S AN EXPERIENCE THAT EVERY SINGLE PERSON HAS TO HAVE ONCE IN THEIR LIFETIME.

>> HERE IN WINTER.

EMILIANO: HERE IN WINTER.

YES, IN WINTER.

AND I LOVE IT - IT'S REALLY COLD, BUT WE LOVE IT.

JOHN: GOOD EVENING, I'M JOHN YANG.

WHITE HOUSE ENVOYS MET AGAIN WITH UKRAINIAN OFFICIALS IN MIAMI TODAY TO DISCUSS PRESIDENT TRUMP'S PROPOSED PATH TO PEACE IN UKRAINE.

IT WAS THEIR SEVENTH MEETING OVER TWO WEEKS, INCLUDING A SESSION THIS PAST SUNDAY THAT INCLUDED SECRETARY OF STATE MARCO RUBIO.

THE STATE DEPARTMENT SAID THEY'VE AGREED ON A KEY ITEM.

A PEACEKEEPING ARRANGEMENT FOR POST-WAR UKRAINE.

THE ADMINISTRATION'S NATIONAL SECURITY STRATEGY, RELEASED THIS WEEK, SAYS ENDING THE WAR IS A "CORE" U.S.

INTEREST "IN ORDER TO STABILIZE EUROPEAN ECONOMIES, PREVENT UNINTENDED ESCALATION OR EXPANSION OF THE WAR, AND REESTABLISH STRATEGIC STABILITY WITH RUSSIA."

THE CONGRESSIONALLY MANDATED DOCUMENT REFLECTS A SHIFT FROM THE STANCE OF PREVIOUS ADMINISTRATIONS, INCLUDING MR.

TRUMP'S FIRST TERM.

EARLIER I SPOKE WITH MATTHEW KROENIG, VICE PRESIDENT AND SENIOR DIRECTOR OF THE ATLANTIC COUNCIL'S SCOWCROFT CENTER FOR STRATEGY AND SECURITY.

HE HELPED WRITE SIMILAR STRATEGY STATEMENTS UNDER PRESIDENTS GEORGE W. BUSH AND OBAMA AND IN THE FIRST TRUMP TERM.

MATTHEW: OVERALL, IT WAS A GOOD DOCUMENT WITH STRENGTHS AND WEAKNESSES.

STRENGTHS, A GOOD STRATEGY SHOULD TELL YOU WHAT IS NEW AND DIFFERENT.

THIS ONE DID THAT WITH A FOCUS ON THE WESTERN HEMISPHERE.

IT ALSO HAD SOME NEW IDEAS FOR NEW CHALLENGES, HOW THE U.S.

CAN MAINTAIN TECHNOLOGICAL LEADERSHIP, SO I THINK THOSE WERE THE STRENGTHS.

ON THE WEAKNESSES, IT DOWNPLAYED DEMOCRACY AND HUMAN RIGHTS, WHICH I THINK IS A MISTAKE.

WAS PROBABLY TOO CRITICAL OF EUROPEAN ALLIES, AND I THINK DOWNPLAYED THE CHALLENGES WE FACE FROM RIVALS LIKE CHINA.

JOHN: AT THE REAGAN NATIONAL DEFENSE FORM YOU ARE AT RIGHT NOW, I EXPECT THERE ARE REPRESENTATIVES FROM EUROPE.

WHAT ARE YOU HEARING FROM THEM OR OTHERS AT THE FORUM ABOUT THE DOCUMENT?

MATTHEW: MIXED OPINIONS ON THE DOCUMENT.

ONE EUROPEAN AMBASSADOR I SPOKE TO LAST NIGHT SAID THIS SEEMS TO BE A CONSISTENT MESSAGE NOW FOLLOWING JD VANCE'S SPEECH AT THE SECURITY CONFERENCE.

IT WOULD BE IRRESPONSIBLE IF YOU ARE A EUROPEAN OFFICIAL NOT TO QUESTION AMERICA'S COMMITMENT TO EUROPE AND THINK ABOUT HOW EUROPE MAY NEED TO GO A DIFFERENT WAY.

JOHN: IT SAYS EUROPE FACES THE PROCESS OF CIVILIZATIONAL ERASURE BECAUSE OF SUPPRESSION OF POLITICAL OPPOSITION.

WHAT IS YOUR REACTION TO THAT?

MATTHEW: I DO THINK THAT IS SOMETHING OF AN EXTENSION OF DOMESTIC POLITICS FOR THE SO-CALLED NEW RIGHT IN THE REPUBLICAN PARTY.

I THINK THEY SEE THEIR ENEMIES'S LIBERALS AND PROGRESSIVES.

THAT IS IN THE U.S., BUT ALSO IN EUROPE.

I THINK TAKING SOME OF THEIR DOMESTIC POLITICAL POSITIONS AND EXPORTING THOSE TO EUROPE IS WHAT ACCOUNTS FOR THOSE PASSAGES.

JOHN: YOU MENTIONED THE ABSENCE OF TALKING ABOUT DEMOCRACY AND HUMAN RIGHTS.

IN THEIR PLACE, IT SEEMS TO BE THE EMPHASIS ON ECONOMIC RELATIONSHIPS AROUND THE WORLD.

WHAT DO YOU THINK OF THAT?

MATTHEW: ALLIES AND PARTNERS IN THE WESTERN HEMISPHERE HAVE OFTEN FELT LIKE THEY ARE OVERLOOKED, THAT THE U.S.

HAS PAID MORE ATTENTION TO EUROPE, THE MIDDLE EAST, AND ASIA.

I THINK THEY SEE THIS NEW FOCUS ON THE WESTERN HEMISPHERE AS OVERALL A GOOD THING.

THERE IS TALK ABOUT ECONOMIC PARTNERSHIPS, SO I THINK THAT MAKES A LOT OF SENSE.

IT IS ONE OF THE STRENGTHS OF THE STRATEGY AND WILL BE WELCOMED BY THE COUNTRIES THAT ARE THE RECIPIENTS.

JOHN: THIS DOCUMENT IS NOT ONLY DIFFERENT FROM PREVIOUS PRESIDENTS, IT IS ALSO DIFFERENT FROM MR.

'S FIRST ADMINISTRATION.

IN THAT DOCUMENT, THE WORLD WAS FRAMED AS COMPETITION BETWEEN THOSE WHO FAVOR MORE OPPRESSIVE SYSTEMS AND THOSE WHO FAVOR FREE SOCIETIES.

WHAT DO YOU MAKE OF THAT CHANGE?

MATTHEW: THAT IS A BIG CHANGE, THE 2017 NATIONAL SECURITY STRATEGY, THE MAIN TAKE AWAY WAS COMPETITION TAKE AWAY FROM CHINA.

THIS DOWNPLAYS OUR RIVALS.

RUSSIA AND CHINA ARE PRESENTED AS NOT POSING MUCH OF A CHALLENGE.

I THINK THE DIFFERENCE IS THE DIFFERENCE IN PERSONNEL, AND TRUMP WAS NEW TO WASHINGTON, SO HE WAS STAFFED BY TRADITIONAL REAGANITE REPUBLICANS.

THIS ADMINISTRATION, HE DOES HAVE TRADITIONAL REPUBLICANS BUT HE ALSO HAS MORE IN THE SO-CALLED RESTRAINT AND POPULIST CAMP, SO I SEE THE FINGERPRINTS ON THIS DOCUMENT.

JOHN: WHAT DO YOU SEE IS THE PRACTICAL IMPACT OF THE DOCUMENT?

SOMETHING CONGRESS MANDATES THAT HAS TO BE PRODUCED, BUT WHAT IS THE PRACTICAL SIGNIFICANCE?

MATTHEW: IT DOES HAVE PRACTICAL IMPLICATIONS.

OUR ALLIES AND ADVERSARIES ARE CAREFULLY READING THE DOCUMENT.

I TALKED ABOUT WITH SEVERAL ALLIES OVER THE PAST 24 HOURS, BUT THEN IT ALSO PROVIDES DIRECTION TO THE VAST AND NATIONAL SECURITY BUREAUCRACIES WITH MID AND LOWER LEVEL OFFICIALS AND THE STATE DEPARTMENT, THE INTELLIGENCE COMMUNITY, THEY WOULD LIKE TO KNOW WHAT THEY SHOULD BE DOING ON A DAY-TO-DAY BASIS, SO THIS DOCUMENT DOES PROVIDE AN AUTHORITATIVE STATEMENT OF THE PRESIDENT'S PRIORITIES.

JOHN: HOW DO YOU THINK THIS IS BEING READ IN BEIJING OR MOSCOW?

MATTHEW: WELL, I THINK THE ANSWER MAY BE DIFFERENT.

IT DOES TALK A LOT ABOUT MAINTAINING DETERRENCE AND KEEPS OUR TRADITIONAL POLICY WITH REGARD TO TAIWAN, TALKS ABOUT RUNNING THE ECONOMIC AND TECHNOLOGY COMPETITIONS WITH CHINA.

THE RUSSIA CHALLENGE IS PRESENTED ALMOST AS SQUABBLING BETWEEN EUROPE AND RUSSIA, AND IT POSITIONS THE U.S.

AS A MEDIATOR, TRYING TO RESTORE STABILITY.

I SUSPECT PUTIN WILL SEE THAT AS A FORWARD FROM HIS POINT OF VIEW COMPARED TO TRADITIONAL STRATEGIES THAT CORRECTLY PORTRAY PRESSURE MORE AS A THREAT TO THEM THAN THE UNITED STATES.

JOHN: THANK YOU VERY MUCH.

MATTHEW: MY PLEASURE.

THANK YOU FOR HAVING ME.

JOHN: IN TONIGHT'S OTHER HEADLINES, ARAB LEADERS SAY IT'S TIME TO MOVE FORWARD ON THE SECOND PHASE OF THE ISRAEL-HAMAS CEASEFIRE.

IN REMARKS TO THE DOHA FORUM, THE QATARI PRIME MINISTER SAID AN ONGOING CEASEFIRE AGREEMENT NEEDS TO INCLUDE THE FULL WITHDRAWAL OF ISRAELI TROOPS FROM THE GAZA STRIP.

THE REMARKS CAME AS ISRAELI DEFENSE FORCES KILLED THREE PEOPLE IN AN ISRAELI-CONTROLLED AREA OF GAZA.

TWO OTHERS DIED IN AN AIRSTRIKE OUTSIDE OF GAZA CITY.

THE NEXT STEPS IN PRESIDENT TRUMP'S PEACE PLAN FOR GAZA CALLED FOR INTERNATIONAL SECURITY FORCE IN GAZA,THE FORMATION OF A NEW GOVERNMENT AND HAMAS GIVING UP ITS WEAPONS, WHICH IT HAS NOT AGREED TO.

DEVASTATION AND DESPERATION ARE EVIDENT IN NEWLY RELEASED 9-1-1 CALLS FROM THE JULY 4TH WEEKEND FLASH FLOODING IN KERR COUNTY, TEXAS.

WE WANT TO WARN YOU THAT SOME VIEWERS MAY FIND THIS DISTRESSING.

DISPATCHER: OK, HOW MANY PEOPLE ARE THERE?

WOMAN: THERE'S THREE.

AND WE'RE - - WE'RE STUCK, AND IT'S TWO ELDERLY PEOPLE.

PLEASE HELP.

I CAN'T -- DISPATCHER: OK REALLY QUICKLY, HEY, REALLY QUICKLY I NEED YOU TO TAKE A REALLY DEEP BREATH -- WOMAN: WE'VE GOT TO GET OUT OF HERE!

DISPATCHER: I UNDERSTAND WE HAVE EVERYBODY HEADED THAT DIRECTION, BUT I NEED YOU TO TAKE A DEEP BREATH, OK?

WOMAN: OK.

DISPATCHER: WHAT'S A GOOD CALLBACK NUMBER FOR YOU?

WOMAN: I CAN'T GET -- I CAN'T GET OUT AND IT'S (UNINTELLIGIBLE) AND I'M SCARED.

JOHN: WE DON'T KNOW WHETHER THE WOMAN IN THAT CALL WAS AMONG THE MORE THAN 130 LIVES LOST IN THE FLOODING.

OVER THE COURSE OF SIX HOURS, AS FLOOD WATERS RUSHED THROUGH THE AREA, DISPATCHERS HANDLED MORE THAN 400 EMERGENCY CALLS.

THE FAMILY OF A NATIONAL GUARD MEMBER AMBUSHED BLOCKS FROM THE WHITE HOUSE SAY THEY'RE OPTIMISTIC ABOUT HIS RECOVERY.

THEY SAY SERGEANT ANDREW WOLFE IS LOOKING MORE LIKE HIMSELF AND HIS "HEAD WOUND IS SLOWLY HEALING."

HE'S EXPECTED TO REMAIN IN ACUTE CARE FOR ANOTHER 2 OR 3 WEEKS.

LAST NIGHT, THERE WAS A VIGIL FOR WOLFE AT HIS OLD HIGH SCHOOL IN BERKELEY COUNTY, WEST VIRGINIA.

ARMY SPECIALIST SARAH BECKSTROM WAS ALSO ATTACKED AND LATER DIED FROM HER INJURIES.

AND THE COUNTDOWN TO THE WINTER OLYMPICS IN ITALY HAS BEGUN.

IN ROME, THE OLYMPIC FLAME BEGAN ITS JOURNEY TO THE GAMES IN MILAN.

OVER THE NEXT TWO MONTHS, MORE THAN 10,000 TORCHBEARERS WILL PARTICIPATE IN A 7,000 MILE RELAY THROUGHOUT ITALY.

THE OPENING CEREMONIES WILL BE HELD ON FEBRUARY 6TH.

STILL TO COME ON "PBS NEWS WEEKEND."

HOW AI IS HELPING PREDICT PREMATURE BIRTHS.

AND, THE RISKS AND REWARDS OF AN ICY PLUNGE.

♪ >> THIS IS PBS NEWS WEEKEND FROM THE DAVIDM.

RUBENSTEIN STUDIO AT WETA WASHINGTON, HOME OF THE PBS NEWS HOUR, WEEKNIGHTS ON PBS.

JOHN: LAST YEAR, ONE IN 10 U.S.

BABIES WAS BORN BEFORE 37 WEEKS OF PREGNANCY, WHICH IS CONSIDERED PRE-TERM.

THE MARCH OF DIMES SAYS THAT'S ONE OF THE HIGHEST PREMATURE BIRTH RATES AMONG DEVELOPED NATIONS.

PRE-TERM BIRTHS CAN HAVE LONGTERM HEALTH EFFECTS AND ARE HARD TO PREDICT.

ALI ROGIN SPOKE WITH AN ENTREPRENEUR WHO'S USING AI TO HELP DOCTORS KNOW WHEN IT'S LIKELY.

BUT FIRST, MARCH OF DIMES HELPED CONNECT ALI WITH PARENTS OF PRETERM BABIES TO HEAR ABOUT THEIR EXPERIENCES.

ERICA SHOEMATE: MY NAME IS ERICA SCHUMATE AND I AM NIA'S MOM.

ROXANNE ROMEO: HI, MY NAME IS ROXANNE ROMEO AND I'M ZARA'S MOM.

LUCERO PAYANO: MY NAME IS LUCERO PAYANO, AND I AM ZAYEL'S MOTHER.

RUBAN CONTRERAS: MY NAME IS RUBEN CONTRERAS AND I'M ZAHEL'S DAD.

ASHLEY O'NEIL: MY NAME IS ASHLEY O'NEILL AND I AM COLIN'S MOM.

EMMA LEE GREENLEY: MY NAME IS EMILY GREENLEY AND I'M LOIS' MOM.

MY BABY WAS BORN AT TWENTY-FOUR WEEKS, TWO DAYS.

SHE WEIGHED ONE POUND SEVEN OUNCES, OR THE BEST THAT THEY COULD MEASURE SO QUICK.

SHE WAS INTUBATED IN THE MIDDLE.

- - IMMEDIATELY.

OXANNE: ZARA WAS BORN AT TWENTY-SIX WEEKS AND FOUR DAYS.

SHE WEIGHED TWO POUNDS, SIX POINT SEVEN OUNCES, AND SHE SPENT NINETY-THREE DAYS IN THE NICU.

LUCERO PAYANO: ZAYEL WAS TWENTY FIVE WEEKS AND TWO DAYS WHEN I DELIVERED HIM.

ERICA SHOEMATE: WE LEARNED THAT MY DAUGHTER ACTUALLY HAS ELLIS VAN KRAVEL SYNDROME, WHICH HAS LESS THAN 300 CASES REPORTED IN THE WORLD, BUT IT'S HIGHLY CONCENTRATED IN THE AMISH DUTCH POPULATION.

IT'S VERY RARE IN GENERAL, BUT THEN TO BE A FAMILY OF COLOR, WE ONLY KNOW TWO OTHER FAMILIES OF COLOR THAT HAVE BEEN DIRECTLY IMPACTED IN THE WORLD.

ASHLEY O'NEIL: I WENT INTO LABOR WITH COLIN AT TWENTY FIVE WEEKS GESTATION AT A SMALL COMMUNITY HOSPITAL THAT DIDN'T HAVE THE RESOURCES TO PROPERLY CARE FOR A CHILD.

HE WAS BORN AT ROUGHLY A POUND AND A HALF.

OXANNE ROMEO: EVERY DAY I WOULD HAVE TO CALL IN THE MORNING TO TALK TO ONE OF THE NICU NURSES TO FIND OUT HOW MANY EPISODES SHE HAD THE NIGHT BEFORE, WHICH IS WHEN A BABY STOPS BREATHING.

AND TO EVEN IMAGINE YOUR CHILD NOT BREATHING IS JUST CRAZY.

ASHLEY O'NEIL: HE FOUGHT, HE WAS A FEISTY LITTLE THING, REPEATEDLY PULLED OUT OF HIS ALL OF HIS TUBES, BUT HE CAME HOME 183 DAYS LATER.

EMMA LEE GREENLEY: LOIS IS FIVE YEARS OLD NOW.

SHE IS IN PRESCHOOL.

SHE IS DOING VERY WELL.

SHE JUST TURNED EIGHT ON SEPTEMBER 27.

IT HAS BEEN AN HONOR, A PRIVILEGE TO BE THIS LITTLE ROCK STAR'S MOM.

RICA SHOEMATE: SHE IS A SPUNKY, SASSY LITTLE TODDLER.

SHE IS GOING TO BE THREE IN DECEMBER.

LUCERO PAYANO: HE IS THANK GOD DOING AMAZING WHEN I TELL PEOPLE THAT HE'S A 25 WEAKER, THEIR JAWS DROP.

RUBAN CONTRERAS: COLIN IS SIX NOW.

HE IS IN THE FIRST GRADE.

HE LOOKS GOOD.

HE IS NUNSPEAKING, USES A COMMUNICATION DEVICE.

HE DOES BOSS ME AROUND.

MOM, IPAD, PLEASE.

HE HAS THE BEST SMILE THAT LIGHTS UP A ROOM.

HE LOVES PLAYING TRICKS ON HIS TEACHERS.

IF THEY ASK HIM A QUESTION, HE'LL HOVER OVER THE RIGHT ANSWER, GIGGLE AND HIT THE WRONG ANSWER AND GIGGLE SOME MORE.

ERICA SHOEMATE: I JUST ENCOURAGE PEOPLE TO LEARN MORE ABOUT PREMATURITY, ESPECIALLY IF YOU KNOW YOU'RE PREGNANT OR IF YOU PLAN TO HAVE A CHILD.

AND I'M NOT JUST TALKING ABOUT WOMEN.

FATHERS NEED TO BE IN THE KNOW AS WELL BECAUSE THEY ARE DEFINITELY PART OF THIS JOURNEY.

ERICA SHOEMATE: TO ANYONE THAT IS NAVIGATING THIS THING THAT YOU NEVER SIGN UP FOR AS A PARENT, JUST KNOW THAT YOU CAN GET THROUGH IT.

THERE IS LIFE AND LOVE ON THE OTHER SIDE.

AND ALSO TO ALLOW YOURSELF THE MOMENTS TO GRIEF, TO GRIEVE THROUGH THE GRIEF OF THE PREGNANCY YOU DIDN'T HAVE, THE PARENTHOOD EXPERIENCE THAT YOU'RE NOT HAVING OR WILL NOT HAVE.

AND TO ALSO NOT ALLOW YOURSELF TO GET IN THE BUSINESS OF COMPARING YOUR CHILD TO SOMEONE ELSE'S WHO IS NOT HAVING THE SAME EXPERIENCE AS YOU.

OXANNE: I SHARE MY STORY A LOT JUST TO TELL OTHER PEOPLE THAT LIKE I KNOW HOW DARK IT CAN DO IT BUT IF YOU JUST KEEP GOING , EVENTUALLY YOU WILL FIND A LIGHT.

IT MAY NOT BE AS BRIGHT AS YOU IMAGINED OR EVEN THE SAME COLOR AS YOU IMAGINE YOUR LIGHT WOULD LOOK LIKE, BUT IT CAN STILL BE BEAUTIFUL NONETHELESS.

ALI ROGIN: WE NOW TURN TO ROBERT BUNN, AN ENTREPRENEUR WHO KNOWS THIS ISSUE FIRSTHAND.

HE AND HIS WIFE HAVE FOUR DAUGHTERS, BUT HIS WIFE EXPERIENCED NINE MISCARRIAGES ALONG THE WAY.

HER EXPERIENCE INSPIRED HIM TO WORK ON TECHNOLOGY THAT CAN HELP PREDICT WHETHER A PREGNANCY WILL END IN A PREMATURE BIRTH AND HELP A MEDICAL TEAM PREPARE FOR THAT OUTCOME.

ROBERT, THANK YOU SO MUCH FOR BEING HERE WITH US.

ROBERT BUNN: THANK YOU, IT'S A PLEASURE TO BE HERE.

ALI ROGIN: TELL ME A LITTLE BIT MORE ABOUT WHAT YOU AND YOUR WIFE WENT THROUGH TO BUILD YOUR FAMILY AND HOW THAT INSPIRED YOU TO BEGIN WORKING IN THIS FIELD.

ROBERT BUNN: SURE, AND WHEN WE WERE BEGINNING TO START OUR FAMILY, MY WIFE SUFFERED NUMEROUS MISCARRIAGES.

AND I WAS BEGINNING TO WONDER WHY THIS COULD HAPPEN OVER AND OVER AND OVER AND AND NOTHING COULD BE DONE ABOUT IT.

FTER DOING A BIT OF RESEARCH, BECAUSE I HAVE NO MEDICAL BACKGROUND, I HAD TO DO SOME RESEARCH TO UNDERSTAND THE PROBLEM.

WHAT I REALIZED IS THAT THE REASON THERE'S SO MANY PREMATURE BIRTHS IS BECAUSE TYPICALLY THEY ARE A SURPRISE.

AND WHEN THEY HAPPEN, IT'S TOO LATE TO DO ANYTHING ABOUT THAT TIME, AND DOCTORS TYPICALLY DON'T HAVE ANY FOREWARNING.

AND I SORT OF THOUGHT MAYBE IF I COULD CREATE AN AI THAT COULD PREDICT THAT A PREMATURE BIRTH IS IMPENDING, THEN DOCTORS WOULD HAVE A FIGHTING CHANCE TO PREVENT THAT AND THEY HAVE TIME TO DO SOMETHING ABOUT IT.

ALI ROGIN: HOW DOES THIS TECHNOLOGY KNOW WHAT TO LOOK FOR AND FLAG ISSUES, POTENTIAL ISSUES?

ROBERT BUNN: I EVENTUALLY LEARNED THAT THE SOLUTION IS IS TO OBTAIN MILLIONS OF ULTRASOUND IMAGES AND THEN I HAVE THE OUTCOMES OF WHAT HAPPENED TO THOSE BABIES IN THOSE IMAGES, AND THEN WHAT I DID IS I CREATED AN AI THAT COULD FIGURE OUT HOW TO MAP THE WHAT WAS THE THE PIXELS IN THE IMAGES TO WHAT ACTUALLY HAPPENED.

AND I HAD TO BUILD A SUPERCOMPUTER FROM PARTS IN MY BASEMENT TO GET THE COMPUTER POWER NECESSARY AND IT TOOK MONTHS TO TRAIN THIS AI, BUT BASICALLY WHAT THE AI EVENTUALLY LEARNED HOW TO DO WAS TO FIND PATTERNS IN THESE IMAGES THAT THEN CORRELATED TO THE ACTUAL OUTCOMES, WHICH OPENED UP A WHOLE LOT OF NEW DISCOVERIES, AS WELL AS THE CAPABILITY TO PREDICT THE DELIVERY DATE OF THESE BABIES, WHICH THEN OF COURSE THE DOCTORS COULD THEN ACT UPON AND DETERMINE IF THAT WAS GOING TO WORK OR IF THEY NEEDED TO DO SOMETHING.

ALI ROGIN: WHY IS IT TRADITIONALLY SO DIFFICULT TO SCREEN FOR PREMATURITY?

ROBERT BUNN: ONE IS BECAUSE ULTRASOUND IMAGES ARE NOT ARE HARD TO READ.

THEY ARE VERY NOISY.

IT'S VERY HARD TO SEE THINGS IN THEM.

THERE ARE SOME THINGS THAT DOCTORS KNOW THAT TYPICALLY LEAD TO PREMATURE BIRTH, BUT THOSE THINGS TYPICALLY ONLY HAPPEN TO A SMALL PERCENTAGE OF WOMEN, BUT THE VAST MAJORITY OF WOMEN IS JUST WE'VE YOU HAVE A HISTORY OF PREMATURE BIRTH OR HISTORY MISCARRIAGES, SO THEREFORE WE'LL MONITOR YOU CLOSELY IN THE FUTURE.

BUT IT IS NOT -- IT IS -- THE ACCURACY IS NOT AS GOOD AS IT COULD BE, AND I THINK THAT IS THE PROBLEM I NEEDED TO SOLVE, TO GIVE DOCTORS VERY PRECISE DELIVERY DATES ON WHEN THESE BABIES WOULD BE DELIVERED SO THEY COULD ACT CONFIDENTLY TO TREAT THEM.

ALI ROGIN: I UNDERSTAND YOUR TECHNOLOGY IS ALREADY BEING USED IN COUNTRIES IN SOUTH AMERICA.

WHAT HAVE THE RESULTS BEEN LIKE THERE?

ROBERT BUNN: THEY'VE BEEN IN TRIAL USE IN BOTH BRAZIL AND CHILE.

THE DOCTORS ARE EXTREMELY HAPPY.

PROBABLY THE BIGGEST THING THAT MAKES THEM HAPPY IS THE FACT THAT IT IS ABLE TO IDENTIFY WOMEN WHO ARE ON THEIR FIRST CHILD WHO MAY HAVE A PREMATURE BIRTH SO THEY CAN MAKE SURE THOSE WOMEN GET THE CARE THEY NEED THEY WOULD NOT HAVE GOTTEN OTHERWISE.

THEN THERE'S ALSO THE CASE WHERE THERE'S HIGH-RISK PREGNANCIES AND THEY WANT TO KEEP THE BABIES IN AS LONG AS POSSIBLE BECAUSE THAT REDUCES TIME IN THE NIQ, - - THE NICU.

AND THEY HAVE A GOOD IDEA OF WHEN THE BABY'S GOING TO SPONTANEOUSLY DELIVER, AND A SPONTANEOUS DELIVER MAY NOT BE THE BEST CHOICE IN THAT CASE, AND THEY CAN DO A C-SECTION RIGHT BEFORE THEN, SO IT HELPS THEM TIME THE DELIVERIES THAT NEED TO BE MUCH BETTER AND HAVE BETTER OUTCOMES.

ALI ROGIN: AND THEN WHAT'S YOUR OUTLOOK FOR BECOMING AVAILABLE TO PEOPLE HERE IN THE U.S.?

ROBERT BUNN: SO WE'VE RECENTLY SUBMITTED OUR A FINAL REVIEW FOR THE FDA AND WE HOPE TO HAVE APPROVAL HERE VERY SOON, MAYBE WITHIN THE NEXT FEW MONTHS.

I THINK LIFE IS UNCERTAIN, BUT WE FEEL VERY GOOD ABOUT THIS TECHNOLOGY AND AND THAT ITS ABILITY TO BEGIN SAVING THE LIVES OF BABIES IN AMERICA HERE TOO.

ALI ROGIN ROBERT BUNN WITH ULTRASOUND AI, THANK YOU SO MUCH.

ROBERT BUNN: THANK YOU.

IT'S A PLEASURE BEING HERE.

♪ OHN: AS THE WINTER SOLSTICE NEARS, IT MIGHT NOT FEEL LIKE THE SEASON FOR JUMPING IN THE WATER, BUT MORE AND MORE PEOPLE ARE FINDING AN ICY PLUNGE INVIGORATING.

IN THIS ENCORE REPORT, WILLIAM BRANGHAM TAKES A LOOK AT THE WORLD OF WINTER SWIMMING AND ITS POTENTIAL BENEFITS AND RISKS.

WILLIAM: EVEN THOUGH THE TEMPERATURES ARE PLUNGING, SO ARE THESE SWIMMERS, A BRAVE GROUP IN THE NORTHERN CHINESE CITY OF HARBIN, TAKING A SUBZERO JUMP, ONE BY ONE, INTO THE WATER.

>> I FELT PRICKLING ALL OVER MY BODY, THE WATER HERE IS ABOUT 10 CELSIUS DEGREES LOWER THAN IT IN MY HOMETOWN BUT IT STILL MADE ME FEEL BLISSFUL.

WILLIAM: THESE HARDY SOULS ARE PART OF THIS CITY'S WINTER SWIMMING TEAM, WHICH BOASTS HUNDREDS OF MEMBERS.

THEY SAY THEY TRAIN THROUGHOUT THE YEAR TO DEVELOP THE PHYSICAL STRENGTH AND MENTAL FORTITUDE NEEDED TO DIVE INTO POOLS CARVED FROM ICE DURING THE CITY'S ANNUAL WINTER FESTIVAL.

>> ONCE THESE CHALLENGES ARE OVERCOME, YOU WILL FEEL THE ENDLESS JOY BROUGHT BY WINTER SWIMMING.

ILLIAM: ENDLESS JOY OR CRAZY OBSESSION?

IN THE CZECH REPUBLIC, LOCALS THERE TAKE TO THE COLD WATERS OF THE VULTAVA RIVER IN EARLY JANUARY TO MARK THE END OF THE CHRISTMAS SEASON.

>> WELL, I'VE STUCK WITH IT.

IT IS A BIT OF AN ADDICTION NOW.

>> ONCE YOU HAVE TRIED IT, YOU HAVE TO KEEP DOING IT.

WILLIAM: IN THE DANISH CAPITAL, COPENHAGEN, IT'S A TOURIST DRAW TO BRAVE THE ICY WATER.

>> IT IS CRAZY.

IT'S REALLY REFRESHING, I THINK IT'S AN EXPERIENCE THAT EVERY SINGLE PERSON HAS TO HAVE ONCE IN THEIR LIFETIME.

>> HERE IN WINTER.

>> YES, IN WINTER, AND I LOVE IT.

IT'S REALLY COLD, BUT WE LOVE IT.

WILLIAM: DEVOTEES OF WINTER SWIMMING ARE CONVINCED THESE BONE CHILLING DIPS BOOST HEALTH AND HAPPINESS.

>> BACK IN THE DAY, I USED TO GET LEG CRAMPS, AND EVER SINCE I STARTED WINTER SWIMMING, IT HAS STOPPED.

>> I AM 76 YEARS OLD BUT I'VE NEVER GOT A COLD BECAUSE I SWIM IN WINTER AND I FEEL VERY WELL.

IT BRINGS ME GOOD HEALTH.

WILLIAM: ONLINE, ADVOCATES SAY THE BENEFITS ARE MANY, HELPING WITH EVERYTHING FROM MIGRAINES TO ARTHRITIS AND EVEN WEIGHT LOSS.

>> IT BOOSTS THE IMMUNE SYSTEM.

>> IT REALLY IMPROVES YOUR MENTAL HEALTH.

>> GREAT BLOOD CIRCULATION, HELPS YOU SLEEP BETTER.

WILLIAM: BUT NOT EVERYONE IS CONVINCED.

>> SOME OF THE CLAIMS THAT YOU'LL SEE THAT SPLASH OVER THE WEB, WE DON'T ACTUALLY HAVE GOOD ROBUST EVIDENCE TO BE ABLE TO TO SUPPORT THOSE CLAIMS AT THE MOMENT.

ILLIAM: HEATHER MASSEY STUDIES COLD-WATER IMMERSION AND SWIMMING AT THE UNIVERSITY OF PORTSMOUTH, IN ENGLAND.

HEATHER MASSEY: THE LEVEL OF SCIENCE FAR IS, IS FAR MORE POWERFUL FROM THE SIDE OF IT HAVING NEGATIVE EFFECTS.

WILLIAM: MASSEY SAYS THE INITIAL PLUNGE INTO ICY WATER IS SHOCKING.

AND THE BODY REACTS INSTANTLY: SHORTNESS OF BREATH, HIGHER BLOOD PRESSURE, EVEN IMPAIRED COGNITIVE FUNCTION.

HEATHER MASSEY: DEFINITELY MAKE SURE YOU'RE WELL FIT AND HEALTHY BEFORE YOU GO IN.

IF YOU'VE GOT ANY UNDERLYING HEALTH PROBLEMS OR YOU'RE NOT FEELING GREAT, GOING IN COLD WATER IS NOT GOING TO HELP.

WILLIAM: SHE SAYS EVEN HEALTHY PEOPLE SHOULD PROCEED WITH CAUTION.

THERE CAN BE THE VERY REAL RISK OF HYPOTHERMIA AND HEART ATTACKS.

BUT MASSEY IS QUICK TO ADD THERE COULD BE HEALTH BENEFITS AND SHE AND OTHER SCIENTISTS ARE LOOKING INTO WHAT THEY ARE.

EATHER MASSEY: IT MAY BE THAT IT'S A PLACEBO EFFECT, BUT IF IT'S A PLACEBO EFFECT AND IT WORKS WELL, IT'S IT'S STILL AN EFFECT.

WILLIAM: EVIDENCE OR NOT, THESE SWIMMERS CAN'T SEEM TO STAY AWAY FROM THEIR ICY PLUNGES, AND THE THRILLS THAT COME WITH IT.

>> IT'S SO COLD, I WILL FREEZE AND I'M SAYING, IF I CAN DO THIS, I CAN DO ANYTHING IN THE WHOLE WORLD.

THAT'S MY FEELING.

ILLIAM: I'M WILLIAM BRANGHAM FOR PBS NEWS WEEKEND.

OHN: AND THAT IS PBS NEWS WEEKEND FOR THIS SATURDAY.

I'M JOHN YANG.

FOR ALL OF MY COLLEAGUES, THANKS FOR JOINING US.

SEE YOU TOMORROW.

♪ > YOU ARE WATCHING PBS.